This article, as written by me, appeared in The Hindu on January 24, 2012.
--
At the Large Hadron Collider (LHC) at CERN, near Geneva, Switzerland, experiments are conducted by many scientists who don’t quite know what they will see, but know how to conduct the experiments that will yield answers to their questions. They accelerate beams of particles called protons to smash into each other, and study the fallout.
There are some other scientists at CERN who know approximately what they will see in experiments, but don’t know how to do the experiment itself. These scientists work with beams of antiparticles. According to the Standard Model, the dominant theoretical framework in particle physics, every particle has a corresponding particle with the same mass and opposite charge, called an anti-particle.
In fact, at the little-known AEgIS experiment, physicists will attempt to produce an entire beam composed of not just anti-particles but anti-atoms by mid-2014.
AEgIS is one of six antimatter experiments at CERN that create antiparticles and anti-atoms in the lab and then study their properties using special techniques. The hope, as Dr. Jeffrey Hangst, the spokesperson for the ALPHA experiment, stated in an email, is “to find out the truth: Do matter and antimatter obey the same laws of physics?”
Spectroscopic and gravitational techniques will be used to make these measurements. They will improve upon, “precision measurements of antiprotons and anti-electrons” that “have been carried out in the past without seeing any difference between the particles and their antiparticles at very high sensitivity,” as Dr. Michael Doser, AEgIS spokesperson, told this Correspondent via email.
The ALPHA and ATRAP experiments will achieve this by trapping anti-atoms and studying them, while the ASACUSA and AEgIS will form an atomic beam of anti-atoms. All of them, anyway, will continue testing and upgrading through 2013.
Working principle
Precisely, AEgIS will attempt to measure the interaction between gravity and antimatter by shooting an anti-hydrogen beam horizontally through a vacuum tube and then measuring how it much sags due to the gravitational pull of the Earth to a precision of 1 per cent.
The experiment is not so simple because preparing anti-hydrogen atoms is difficult. As Dr. Doser explained, “The experiments concentrate on anti-hydrogen because that should be the most sensitive system, as it is not much affected by magnetic or electric fields, contrary to charged anti-particles.”
First, antiprotons are derived from the Antiproton Decelerator (AD), a particle storage ring which “manufactures” the antiparticles at a low energy. At another location, a nanoporous plate is bombarded with anti-electrons, resulting in a highly unstable mixture of both electrons and anti-electrons called positronium (Ps).
The Ps is then excited to a specific energy state by exposure to a 205-nanometre laser and then an even higher energy state called a Rydberg level using a 1,670-nanometre laser. Last, the excited Ps traverses a special chamber called a recombination trap, when it mixes with antiprotons that are controlled by precisely tuned magnetic fields. With some probability, an antiproton will “trap” an anti-electron to form an anti-hydrogen atom.
Applications
Before a beam of such anti-hydrogen atoms is generated, however, there are problems to be solved. They involve large electric and magnetic fields to control the speed of and collimate the beams, respectively, and powerful cryogenic systems and ultra-cold vacuums. Thus, Dr. Doser and his colleagues will spend many months making careful changes to the apparatus to ensure these requirements work in tandem by 2014.
While antiparticles were first discovered in 1959, “until recently, it was impossible to measure anything about anti-hydrogen,” Dr. Hangst wrote. Thus, the ALPHA and AEgIS experiments at CERN provide a seminal setting for exploring the world of antimatter.
Anti-particles have been used effectively in many diagnostic devices such as PET scanners. Consequently, improvements in our understanding of them feed immediately into medicine. To name an application: Antiprotons hold out the potential of treating tumors more effectively.
In fact, the feasibility of this application is being investigated by the ACE experiment at CERN.
In the words of Dr. Doser: “Without the motivation of attempting this experiment, the experts in the corresponding fields would most likely never have collaborated and might well never have been pushed to solve the related interdisciplinary problems.”
Showing posts with label particle physics. Show all posts
Showing posts with label particle physics. Show all posts
Wednesday, 23 January 2013
Wednesday, 21 November 2012
Window for an advanced theory of particles closes further
A version of this article, as written by me, appeared in The Hindu on November 22, 2012.
--
On November 12, at the first day of the Hadron Collider Physics Symposium at Kyoto, Japan, researchers presented a handful of results that constrained the number of hiding places for a new theory of physics long believed to be promising.
Members of the team from the LHCb detector on the Large Hadron Collider (LHC) experiment located on the border of France and Switzerland provided evidence of a very rare particle-decay. The rate of the decay process was in fair agreement with an older theory of particles' properties, called the Standard Model (SM), and deviated from the new theory, called Supersymmetry.
"Theorists have calculated that, in the Standard Model, this decay should occur about 3 times in every billion total decays of the particle," announced Pierluigi Campana, LHCb spokesperson. "This first measurement gives a value of around 3.2 per billion, which is in very good agreement with the prediction."
The result was presented at the 3.5-sigma confidence level, which corresponds to an error rate of 1-in-2,000. While not strong enough to claim discovery, it is valid as evidence.
The particle, called a Bs0 meson, decayed from a bottom antiquark and strange quark pair into two muons. According to the SM, this is a complex and indirect decay process: the quarks exchange a W boson particle, turn into a top-antitop quark pair, which then decays into a Z boson or a Higgs boson. The boson then decays to two muons.
This indirect decay is called a quantum loop, and advanced theories like Supersymmetry predict new, short-lived particles to appear in such loops. The LHCb, which detected the decays, reported no such new particles.
[caption id="attachment_24512" align="aligncenter" width="584"]
The solid blue line shows post-decay muons from all events, and the red dotted line shows the muon-decay event from the B(s)0 meson. Because of a strong agreement with the SM, SUSY may as well abandon this bastion.[/caption]
At the same time, in June 2011, the LHCb had announced that it had spotted hints of supersymmetric particles at 3.9-sigma. Thus, scientists will continue to conduct tests until they can stack 3.5 million-to-1 odds for or against Supersymmetry to close the case.
As Prof. Chris Parkes, spokesperson for the UK participation in the LHCb experiment, told BBC News: "Supersymmetry may not be dead but these latest results have certainly put it into hospital."
The symposium, which concluded on November 16, also saw the release of the first batch of data generated in search of the Higgs boson since the initial announcement on July 4 this year.
The LHC can't observe the Higgs boson directly because it quickly decays into lighter particles. So, physicists count up the lighter particles and try to see if some of those could have come from a momentarily existent Higgs.
These are still early days, but the data seems consistent with the predicted properties of the elusive particle, giving further strength to the validity of the SM.
Dr. Rahul Sinha, a physicist at the Institute of Mathematical Sciences, Chennai, said, “So far there is nothing in the Higgs data that indicates that it is not the Higgs of Standard Model, but a conclusive statement cannot be made as yet.”
The scientific community, however, is disappointed as there are fewer channels for new physics to occur. While the SM is fairly consistent with experimental findings, it is still unable to explain some fundamental problems.
One, called the hierarchy problem, asks why some particles are much heavier than others. Supersymmetry is theoretically equipped to provide the answer, but experimental findings are only thinning down its chances.
Commenting on the results, Dr. G. Rajasekaran, scientific adviser to the India-based Neutrino Observatory being built at Theni, asked for patience. “Supersymmetry implies the existence of a whole new world of particles equaling our known world. Remember, we took a hundred years to discover the known particles starting with the electron.”
With each such tightening of the leash, physicists return to the drawing board and consider new possibilities from scratch. At the same time, they also hope that the initial results are wrong. "We now plan to continue analysing data to improve the accuracy of this measurement and others which could show effects of new physics," said Campana.
So, while the area where a chink might be found in the SM armour is getting smaller, there is hope that there is a chink somewhere nonetheless.
--
On November 12, at the first day of the Hadron Collider Physics Symposium at Kyoto, Japan, researchers presented a handful of results that constrained the number of hiding places for a new theory of physics long believed to be promising.
Members of the team from the LHCb detector on the Large Hadron Collider (LHC) experiment located on the border of France and Switzerland provided evidence of a very rare particle-decay. The rate of the decay process was in fair agreement with an older theory of particles' properties, called the Standard Model (SM), and deviated from the new theory, called Supersymmetry.
"Theorists have calculated that, in the Standard Model, this decay should occur about 3 times in every billion total decays of the particle," announced Pierluigi Campana, LHCb spokesperson. "This first measurement gives a value of around 3.2 per billion, which is in very good agreement with the prediction."
The result was presented at the 3.5-sigma confidence level, which corresponds to an error rate of 1-in-2,000. While not strong enough to claim discovery, it is valid as evidence.
The particle, called a Bs0 meson, decayed from a bottom antiquark and strange quark pair into two muons. According to the SM, this is a complex and indirect decay process: the quarks exchange a W boson particle, turn into a top-antitop quark pair, which then decays into a Z boson or a Higgs boson. The boson then decays to two muons.
This indirect decay is called a quantum loop, and advanced theories like Supersymmetry predict new, short-lived particles to appear in such loops. The LHCb, which detected the decays, reported no such new particles.
[caption id="attachment_24512" align="aligncenter" width="584"]
The solid blue line shows post-decay muons from all events, and the red dotted line shows the muon-decay event from the B(s)0 meson. Because of a strong agreement with the SM, SUSY may as well abandon this bastion.[/caption]At the same time, in June 2011, the LHCb had announced that it had spotted hints of supersymmetric particles at 3.9-sigma. Thus, scientists will continue to conduct tests until they can stack 3.5 million-to-1 odds for or against Supersymmetry to close the case.
As Prof. Chris Parkes, spokesperson for the UK participation in the LHCb experiment, told BBC News: "Supersymmetry may not be dead but these latest results have certainly put it into hospital."
The symposium, which concluded on November 16, also saw the release of the first batch of data generated in search of the Higgs boson since the initial announcement on July 4 this year.
The LHC can't observe the Higgs boson directly because it quickly decays into lighter particles. So, physicists count up the lighter particles and try to see if some of those could have come from a momentarily existent Higgs.
These are still early days, but the data seems consistent with the predicted properties of the elusive particle, giving further strength to the validity of the SM.
Dr. Rahul Sinha, a physicist at the Institute of Mathematical Sciences, Chennai, said, “So far there is nothing in the Higgs data that indicates that it is not the Higgs of Standard Model, but a conclusive statement cannot be made as yet.”
The scientific community, however, is disappointed as there are fewer channels for new physics to occur. While the SM is fairly consistent with experimental findings, it is still unable to explain some fundamental problems.
One, called the hierarchy problem, asks why some particles are much heavier than others. Supersymmetry is theoretically equipped to provide the answer, but experimental findings are only thinning down its chances.
Commenting on the results, Dr. G. Rajasekaran, scientific adviser to the India-based Neutrino Observatory being built at Theni, asked for patience. “Supersymmetry implies the existence of a whole new world of particles equaling our known world. Remember, we took a hundred years to discover the known particles starting with the electron.”
With each such tightening of the leash, physicists return to the drawing board and consider new possibilities from scratch. At the same time, they also hope that the initial results are wrong. "We now plan to continue analysing data to improve the accuracy of this measurement and others which could show effects of new physics," said Campana.
So, while the area where a chink might be found in the SM armour is getting smaller, there is hope that there is a chink somewhere nonetheless.
Tuesday, 17 July 2012
Signs of a slowdown
The way ahead for particle physics seems dully lit after CERN's fourth-of-July firecracker. The Higgs announcement got everyone in the physics community excited - and spurred a frenzied submission of pre-prints all rushing to explain the particle's properties. However, that excitement quickly died out after ICHEP '12 was presented with nothing significant, even with anything a fraction as significant as the ATLAS/CMS results.
[caption id="attachment_23677" align="aligncenter" width="600"]
(L-R) Gianotti, Heuer & Incandela[/caption]
Even so, I suppose we must wait at least another 3 months before a a conclusive Higgs-centric theory emerges that completely integrates the Higgs mechanism with the extant Standard Model.
The spotting of the elusive boson - or an impostor - closes a decades-old chapter in particle physics, but does almost nothing in pointing the way ahead apart from verifying the process of mass-formation. Even theoretically, the presence of SM quadratic divergences in the mass of the Higgs boson prove a resilient barrier to correct. How the Higgs field will be used as a tool in detecting other particles and the properties of other entities is altogether unclear.
The tricky part lies in working out the intricacies of the hypotheses that promise to point the way ahead. The most dominant amongst them is supersymmetry (SUSY). In fact, hints of existence of supersymmetric partners were recorded when the LHCb detector at the LHC spotted evidence of CP-violation in muon-decay events (the latter at 3.9σ). At the same time, the physicists I'm in touch with at IMS point out that rigid restrictions have been instituted on the discovery of sfermions and bosinos.
The energies at which these partners could be found are beyond those achievable by the LHC, let alone the luminosity. More, any favourable-looking ATLAS/CMS SUSY-results - which are simply interpretations of strange events - are definitely applicable only in narrow and very special scenarios. Such a condition is inadmissible when we're actually in the hunt for frameworks that could explain grander phenomena. Like the link itself says,
Despite this bleak outlook, there is still a possibility that SUSY may stand verified in the future. Right now: "Could SUSY be masked behind general gauge mediation, R-parity violation or gauge-mediated SUSY-breaking" is the question (gauge-mediated SUSY-breaking (GMSB) is when some hidden sector breaks SUSY and communicates the products to the SM via messenger fields). Also, ZEUS/DESY results (generated by e-p DIS studies) are currently being interpreted.
However, everyone knows that between now and a future that contains a verified-SUSY, hundreds of financial appeals stand in the way. :D This is a typical time of slowdown - a time we must use for open-minded hypothesizing, discussion, careful verification, and, importantly, honest correction.
[caption id="attachment_23677" align="aligncenter" width="600"]
(L-R) Gianotti, Heuer & Incandela[/caption]Even so, I suppose we must wait at least another 3 months before a a conclusive Higgs-centric theory emerges that completely integrates the Higgs mechanism with the extant Standard Model.
The spotting of the elusive boson - or an impostor - closes a decades-old chapter in particle physics, but does almost nothing in pointing the way ahead apart from verifying the process of mass-formation. Even theoretically, the presence of SM quadratic divergences in the mass of the Higgs boson prove a resilient barrier to correct. How the Higgs field will be used as a tool in detecting other particles and the properties of other entities is altogether unclear.
The tricky part lies in working out the intricacies of the hypotheses that promise to point the way ahead. The most dominant amongst them is supersymmetry (SUSY). In fact, hints of existence of supersymmetric partners were recorded when the LHCb detector at the LHC spotted evidence of CP-violation in muon-decay events (the latter at 3.9σ). At the same time, the physicists I'm in touch with at IMS point out that rigid restrictions have been instituted on the discovery of sfermions and bosinos.
The energies at which these partners could be found are beyond those achievable by the LHC, let alone the luminosity. More, any favourable-looking ATLAS/CMS SUSY-results - which are simply interpretations of strange events - are definitely applicable only in narrow and very special scenarios. Such a condition is inadmissible when we're actually in the hunt for frameworks that could explain grander phenomena. Like the link itself says,
"The searches leave little room for SUSY inside the reach of the existing data."
Despite this bleak outlook, there is still a possibility that SUSY may stand verified in the future. Right now: "Could SUSY be masked behind general gauge mediation, R-parity violation or gauge-mediated SUSY-breaking" is the question (gauge-mediated SUSY-breaking (GMSB) is when some hidden sector breaks SUSY and communicates the products to the SM via messenger fields). Also, ZEUS/DESY results (generated by e-p DIS studies) are currently being interpreted.
However, everyone knows that between now and a future that contains a verified-SUSY, hundreds of financial appeals stand in the way. :D This is a typical time of slowdown - a time we must use for open-minded hypothesizing, discussion, careful verification, and, importantly, honest correction.
Thursday, 12 July 2012
A dilemma of the auto-didact
If publishers could never imagine that there are people who could teach themselves particle physics, why conceive cheaper preliminary textbooks and ridiculously expensive advanced textbooks? Learning vector physics for classical mechanics costs Rs. 245 while progressing then to analytical mechanics involves an incurrence of Rs. 4,520. Does the cost barrier exist because the knowledge is more specialized? If this is the case, then such books should have become cheaper over time. They have not: Analytical Mechanics, which a good friend recommended, has stayed in the vicinity of $75 for the last three years (now, it's $78.67 for the original paperback and $43 for a used one). This is just a handy example. There are a host of textbooks that detail concepts in advanced physics and cost a fortune: all you have to do is look for those that contain "hadron", "accelerator", "QCD", etc., in their titles.
Getting to a place in time where a student is capable of understanding these subjects is cheap. In other words, the cost of aspirations is low while the price of execution is prohibitive.
Sure, alternatives exist, such as libraries and university archives. However, that misses the point: it seems the costs of the books are higher to prevent their ubiquitous consumption. No other reason seems evident, although I am loth to reach this conclusion. If you, the publisher, want me to read such books only in universities, then you are effectively requiring me to either abstain from reading these books irrespective of my interests if my professional interests reside elsewhere or depend on universities and university-publisher relationships for my progress in advanced physics, not myself. The resulting gap between the layman and the specialist eventually evades spanning, leading to ridiculous results such as not understanding the "God" in "God particle" to questioning the necessity of the LHC without quite understanding what it does and how that helps mankind.
Getting to a place in time where a student is capable of understanding these subjects is cheap. In other words, the cost of aspirations is low while the price of execution is prohibitive.
Sure, alternatives exist, such as libraries and university archives. However, that misses the point: it seems the costs of the books are higher to prevent their ubiquitous consumption. No other reason seems evident, although I am loth to reach this conclusion. If you, the publisher, want me to read such books only in universities, then you are effectively requiring me to either abstain from reading these books irrespective of my interests if my professional interests reside elsewhere or depend on universities and university-publisher relationships for my progress in advanced physics, not myself. The resulting gap between the layman and the specialist eventually evades spanning, leading to ridiculous results such as not understanding the "God" in "God particle" to questioning the necessity of the LHC without quite understanding what it does and how that helps mankind.
Wednesday, 11 July 2012
The Indian Bose in the universal boson
Read this article.
Do you think Indians are harping too much about the lack of mention of Satyendra Nath Bose's name in the media coverage of the CERN announcement last week? The articles in Hindustan Times and Economic Times seemed to be taking things too far with anthropological analyses that have nothing to do with Bose's work. The boson was named so around 1945 by the great Paul Dirac as a commemoration of Bose's work with Einstein. Much has happened since; why would we want to celebrate the Bose in the boson again and again?
[caption id="attachment_23631" align="aligncenter" width="275"]
Dr. Satyendra Nath Bose[/caption]
The stage now belongs to the ATLAS and the CMS collaborations, and to Higgs, Kibble, Englert, Brout, Guralnik, and Hagen, and to physics itself as a triumph of worldwide cooperation in the face of many problems. Smarting because an Indian's mention was forgotten is jejune. Then again, this is mostly the layman and the media, because the physicists I met last week seemed to fully understand Bose's contribution to the field itself instead of count the frequency of his name's mention.
Priyamvada Natarajan, as she writes in the Hindustan Times, is wrong (and the Economic Times article's heading is just irritating). That Bose is not a household name like Einstein's is is not because of post-colonialism - the exceptions are abundant enough to warrant inclusion - but because we place too much faith in a name instead of remembering what the man behind the name did for physics.
Do you think Indians are harping too much about the lack of mention of Satyendra Nath Bose's name in the media coverage of the CERN announcement last week? The articles in Hindustan Times and Economic Times seemed to be taking things too far with anthropological analyses that have nothing to do with Bose's work. The boson was named so around 1945 by the great Paul Dirac as a commemoration of Bose's work with Einstein. Much has happened since; why would we want to celebrate the Bose in the boson again and again?
[caption id="attachment_23631" align="aligncenter" width="275"]
Dr. Satyendra Nath Bose[/caption]The stage now belongs to the ATLAS and the CMS collaborations, and to Higgs, Kibble, Englert, Brout, Guralnik, and Hagen, and to physics itself as a triumph of worldwide cooperation in the face of many problems. Smarting because an Indian's mention was forgotten is jejune. Then again, this is mostly the layman and the media, because the physicists I met last week seemed to fully understand Bose's contribution to the field itself instead of count the frequency of his name's mention.
Priyamvada Natarajan, as she writes in the Hindustan Times, is wrong (and the Economic Times article's heading is just irritating). That Bose is not a household name like Einstein's is is not because of post-colonialism - the exceptions are abundant enough to warrant inclusion - but because we place too much faith in a name instead of remembering what the man behind the name did for physics.
Sunday, 8 July 2012
Thursday, 5 July 2012
Gunning for the goddamned: ATLAS results explained
Here are some of the photos from the CERN webcast yesterday (July 4, Wednesday), with an adjoining explanation of the data presented in each one and what it signifies.
This first image shows the data accumulated post-analysis of the diphoton decay mode of the Higgs boson. In simpler terms, physicists first put together all the data they had that resulted from previously known processes. This constituted what's called the background. Then, they looked for signs of any particle that seemed to decay into two energetic photons, or gamma rays, in a specific energy window; in this case, 100-160 GeV.
Finally, knowing how the number of events would vary in a scenario without the Higgs boson, a curve was plotted that fit the data perfectly: the number of events at each energy level v. the energy level at which it was tracked. This way, a bump in the curve during measurement would mean there was a particle previously unaccounted for that was causing an excess of diphoton decay events at a particular energy.
This is the plot of the mass of the particle being looked for (x-axis) versus the confidence level with which it has (or has not, depending n how you look at it) been excluded as an event to focus on. The dotted horizontal line, corresponding to 1μ, marks off a 95% exclusion limit: any events registered above the line can be claimed as having been observed with "more than 95% confidence" (colloquial usage).
Toward the top-right corner of the image are some numbers. 7 TeV and 8 TeV are the values of the total energy going into each collision before and after March, 2012, respectively. The beam energy was driven up to increase the incidence of decay events corresponding to Higgs-boson-like particles, which, given the extremely high energy at which they exist, are viciously short-lived. In experiments that were run between March and July, physicists at CERN reported an increase of almost 25-30% of such events.
The two other numbers indicate the particle accelerator's integrated luminosity. In particle physics, luminosity is measured as the number of particles that can pass detected through a unit of area per second. The integrated luminosity is the same value but measured over a period of time. In the case of the LHC, after the collision energy was vamped up, the luminosity, too, had to be increased: from about 4.7 fb-1 to 5.8 fb-1. You'll want to Wiki the unit of area called barn. Some lighthearted physics talk there.
In this plot, the y-axis on the left shows the chances of error, and the corresponding statistical significance on the right. When the chances of an error stand at 1, the results are not statistically significant at all because every observation is an error! But wait a minute, does that make sense? How can all results be errors? Well, when looking for one particular type of event, any event that is not this event is an error.
Thus, as we move toward the ~125 GeV mark, the number of statistically significant results shoot up drastically. Looking closer, we see two results registered just beyond the 5-sigma mark, where the chances of error are 1 in 3.5 million. This means that if the physicists created just those conditions that resulted in this >5σ (five-sigma) observation 3.5 million times, only once will a random fluctuation play impostor.
Also, notice how the differences between each level of statistical significance increases with increasing significance? For chances of errors: 5σ - 4σ > 4σ - 3σ > ... > 1σ - 0σ. This means that the closer physicists get to a discovery, the exponentially more precise they must be!
OK, this is a graph showing the mass-distribution for the four-lepton decay mode, referred to as a channel by those working on the ATLAS and CMS collaborations (because there are separate channels of data-taking for each decay-mode). The plotting parameters are the same as in the first plot in this post except for the scale of the x-axis, which goes all the way from 0 to 250 GeV. Now, between 120 GeV and 130 GeV, there is an excess of events (light blue). Physicists know it is an excess and not at par with expectations because theoretical calculations made after discounting a Higgs-boson-like decay event show that, in that 10 GeV, only around 5.3 events are to be expected, as opposed to the 13 that turned up.
This first image shows the data accumulated post-analysis of the diphoton decay mode of the Higgs boson. In simpler terms, physicists first put together all the data they had that resulted from previously known processes. This constituted what's called the background. Then, they looked for signs of any particle that seemed to decay into two energetic photons, or gamma rays, in a specific energy window; in this case, 100-160 GeV.
Finally, knowing how the number of events would vary in a scenario without the Higgs boson, a curve was plotted that fit the data perfectly: the number of events at each energy level v. the energy level at which it was tracked. This way, a bump in the curve during measurement would mean there was a particle previously unaccounted for that was causing an excess of diphoton decay events at a particular energy.
This is the plot of the mass of the particle being looked for (x-axis) versus the confidence level with which it has (or has not, depending n how you look at it) been excluded as an event to focus on. The dotted horizontal line, corresponding to 1μ, marks off a 95% exclusion limit: any events registered above the line can be claimed as having been observed with "more than 95% confidence" (colloquial usage).
Toward the top-right corner of the image are some numbers. 7 TeV and 8 TeV are the values of the total energy going into each collision before and after March, 2012, respectively. The beam energy was driven up to increase the incidence of decay events corresponding to Higgs-boson-like particles, which, given the extremely high energy at which they exist, are viciously short-lived. In experiments that were run between March and July, physicists at CERN reported an increase of almost 25-30% of such events.
The two other numbers indicate the particle accelerator's integrated luminosity. In particle physics, luminosity is measured as the number of particles that can pass detected through a unit of area per second. The integrated luminosity is the same value but measured over a period of time. In the case of the LHC, after the collision energy was vamped up, the luminosity, too, had to be increased: from about 4.7 fb-1 to 5.8 fb-1. You'll want to Wiki the unit of area called barn. Some lighthearted physics talk there.
In this plot, the y-axis on the left shows the chances of error, and the corresponding statistical significance on the right. When the chances of an error stand at 1, the results are not statistically significant at all because every observation is an error! But wait a minute, does that make sense? How can all results be errors? Well, when looking for one particular type of event, any event that is not this event is an error.
Thus, as we move toward the ~125 GeV mark, the number of statistically significant results shoot up drastically. Looking closer, we see two results registered just beyond the 5-sigma mark, where the chances of error are 1 in 3.5 million. This means that if the physicists created just those conditions that resulted in this >5σ (five-sigma) observation 3.5 million times, only once will a random fluctuation play impostor.
Also, notice how the differences between each level of statistical significance increases with increasing significance? For chances of errors: 5σ - 4σ > 4σ - 3σ > ... > 1σ - 0σ. This means that the closer physicists get to a discovery, the exponentially more precise they must be!
OK, this is a graph showing the mass-distribution for the four-lepton decay mode, referred to as a channel by those working on the ATLAS and CMS collaborations (because there are separate channels of data-taking for each decay-mode). The plotting parameters are the same as in the first plot in this post except for the scale of the x-axis, which goes all the way from 0 to 250 GeV. Now, between 120 GeV and 130 GeV, there is an excess of events (light blue). Physicists know it is an excess and not at par with expectations because theoretical calculations made after discounting a Higgs-boson-like decay event show that, in that 10 GeV, only around 5.3 events are to be expected, as opposed to the 13 that turned up.
Tuesday, 3 July 2012
So, is it going to be good news tomorrow?
As the much-anticipated lead-up to the CERN announcement on Wednesday unfolds, the scientific community is rife with many speculations and few rumours. In spite of this deluge, it may be that we could expect a confirmation of the God particle’s existence in the seminar called by physicists working on the Large Hadron Collider (LHC).
The most prominent indication of good news is that five of the six physicists who theorized the Higgs mechanism in a seminal paper in 1964 have been invited to the meeting. The sixth physicist, Robert Brout, passed away in May 2011. Peter Higgs, the man for whom the mass-giving particle is named, has also agreed to attend.
The other indication is much more subtle but just as effective. Dr. Rahul Sinha, a professor of high-energy physics and a participant in the Japanese Belle collaboration, said, “Hints of the Higgs boson have already been spotted in the energy range in which LHC is looking. If it has to be ruled out, four-times as much statistical data should have been gathered to back it up, but this has not been done.”
The energy window which the LHC has been combing through was based on previous searches for the particle at the detector during 2010 and at the Fermilab’s Tevatron before that. While the CERN-based machine is looking for signs of two-photon decay of the notoriously unstable boson, the American legend looked for signs of the boson’s decay into two bottom quarks.
Last year, on December 13, CERN announced in a press conference that the particle had been glimpsed in the vicinity of 127 GeV (GeV, or giga-electron-volt, is used as a measure of particle energy and, by extension of the mass-energy equivalence, its mass).
However, scientists working on the ATLAS detector, which is heading the search, could establish only a statistical significance of 2.3 sigma then, or a 1-in-50 chance of error. To claim a discovery, a 5-sigma result is required, where the chances of errors are one in 3.5 million.
Scientists, including Dr. Sinha and his colleagues, are hoping for a 4-sigma result announcement on Wednesday. If they get it, the foundation stone will have been set for physicists to explore further into the nature of fundamental particles.
Dr. M.V.N. Murthy, who is currently conducting research in high-energy physics at the Institute of Mathematical Sciences (IMS), said, “Knowing the mass of the Higgs boson is the final step in cementing the Standard Model.” The model is a framework of all the fundamental particles and dictates their behaviour. “Once we know the mass of the particle, we can move on and explore the nature of New Physics. It is just around the corner,” he added.
The most prominent indication of good news is that five of the six physicists who theorized the Higgs mechanism in a seminal paper in 1964 have been invited to the meeting. The sixth physicist, Robert Brout, passed away in May 2011. Peter Higgs, the man for whom the mass-giving particle is named, has also agreed to attend.
The other indication is much more subtle but just as effective. Dr. Rahul Sinha, a professor of high-energy physics and a participant in the Japanese Belle collaboration, said, “Hints of the Higgs boson have already been spotted in the energy range in which LHC is looking. If it has to be ruled out, four-times as much statistical data should have been gathered to back it up, but this has not been done.”
The energy window which the LHC has been combing through was based on previous searches for the particle at the detector during 2010 and at the Fermilab’s Tevatron before that. While the CERN-based machine is looking for signs of two-photon decay of the notoriously unstable boson, the American legend looked for signs of the boson’s decay into two bottom quarks.
Last year, on December 13, CERN announced in a press conference that the particle had been glimpsed in the vicinity of 127 GeV (GeV, or giga-electron-volt, is used as a measure of particle energy and, by extension of the mass-energy equivalence, its mass).
However, scientists working on the ATLAS detector, which is heading the search, could establish only a statistical significance of 2.3 sigma then, or a 1-in-50 chance of error. To claim a discovery, a 5-sigma result is required, where the chances of errors are one in 3.5 million.
Scientists, including Dr. Sinha and his colleagues, are hoping for a 4-sigma result announcement on Wednesday. If they get it, the foundation stone will have been set for physicists to explore further into the nature of fundamental particles.
Dr. M.V.N. Murthy, who is currently conducting research in high-energy physics at the Institute of Mathematical Sciences (IMS), said, “Knowing the mass of the Higgs boson is the final step in cementing the Standard Model.” The model is a framework of all the fundamental particles and dictates their behaviour. “Once we know the mass of the particle, we can move on and explore the nature of New Physics. It is just around the corner,” he added.
Wednesday, 2 May 2012
New particle discovered at the LHC
In the beginning, the hunt for new particles was exciting: it had ingenuity, creativity, technology and perseverance on display. New constituents of matter would be found, experimented with, and added to a slowly growing list that would cement our understanding of the universe. Now, however, high-energy detectors churn out exotic phenomena like adding clothes to a laundry list. Though the Higgs boson still commands sizeable attention because of its elusive nature and its underpinnings in the Standard Model, other less-important particles are studied as offshoots of more-important interactions. Only as theoretical physics evolves to understand the importance of these exotic particles will their significance be truly understood. Till then, all we can do is pay as much attention to what has happened as we can and understand why these beings could be important.
The latest amongst these beings is the "beauty baryon". Baryons are particles that are composed of three quarks, and any baryon that has one bottom quark becomes a bottom- or beauty-baryon. While their existence has been theorized, this is the first time they've been spotted - at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The CMS is one of the six detectors that dot the underground ring of the LHC, and is built to study particles with relatively higher masses (of the order of some billions of electron-volts). The "beauty baryon" or, to put it correctly, χb* (pronounced "chi-bee-star"), has been spotted at a 5-sigma confidence level. This means that the accuracy of the measurement is 99.99 per cent.
The latest amongst these beings is the "beauty baryon". Baryons are particles that are composed of three quarks, and any baryon that has one bottom quark becomes a bottom- or beauty-baryon. While their existence has been theorized, this is the first time they've been spotted - at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The CMS is one of the six detectors that dot the underground ring of the LHC, and is built to study particles with relatively higher masses (of the order of some billions of electron-volts). The "beauty baryon" or, to put it correctly, χb* (pronounced "chi-bee-star"), has been spotted at a 5-sigma confidence level. This means that the accuracy of the measurement is 99.99 per cent.
Saturday, 18 February 2012
The learner as far-seer
I recall a trivial incident from December 13, 2011, which was the day when the ATLAS and CMS experiments at the CERN's Large Hadron Collider (LHC) announced a possible sighting of the Higgs boson particle. It was not so much an incident as something I'm observing now: when the announcement was being made by Fabiola Gianotti, who's in-charge of ATLAS, I had to pause the live-streamed video once every few seconds to look up what she was talking about. A 20-minute-long presentation took more an hour to be understood.
The reason I remember the experience is that, more often than not, one doesn't know when the learning phase of life ends - many, like me, don't even know what comes after it if it ends. However, earlier today, when I was reading a journal article on using laser-induced plasma and the technology's application in particle accelerators, I surprised myself by understanding the entire thing without stopping even once; I could get what the authors were saying even when they were speaking only via formulae.
It was strangely dejecting because one of the most likeable things about particle physics in my opinion is its tendency to throw up previously unknown information just when we least expect it. In fact, even the one thing we thought we knew about this universe - the highest speed possible - was defied last year by some 15,000 neutrinos. And in such a scenario, when the picture suddenly becomes clear, when I can see the jigsaw puzzle board and the different empty shapes here and there waiting to be filled, it's as if I'm ready to start answering the bigger questions and leave the smaller ones behind.
[caption id="attachment_21624" align="aligncenter" width="334" caption="Clinton Davisson (left) and Lester Germer conducted an experiment since named after them - as the Davisson-Germer experiment - in 1927. Six years earlier, Einstein had won the Nobel Prize in physics for his discovery that particles were discrete encapsulations of energy called quanta. In 1927, French physicist Louis de Broglie presented his thesis that all particles have a wave-like characteristic. In the Davisson-Germer experiment, the two Americans stumbled across an electron diffraction pattern where they were expecting an electron diffuse-reflection pattern while studying the surface of nickel. This proved de Broglie's informed conjecture true."]
[/caption]
I feel like the depressed man whose psychiatrist suggests he witness a performance by a clown in town. The depressed man then admits he is that clown.
At this point, I see two outcomes. The first one hints that I only want to keep learning and I'm not as interested in "deploying" that knowledge usefully. That is only partly true because, hey, I don't have a particle collider in my backyard that introduces new particles into my life so I can piece the universal puzzle together better. The second outcome suggests that my knowing a lot of things - science-wise and not - is, for the most part, a product of this fear of what-will-or-won't-come-next.
The first outcome doesn't bother me much because I've discovered I like teaching. Even though I may not be using my knowledge of IC engines to fix vehicles on desolate highways, I try and ensure as many people as possible understand how such engines work and do what they want with that knowledge. The same applies for particle physics. However, in this case, the dimension of teaching acquires more weight because its capacity to be misunderstood is great: it's a developing field whose foundations are currently under fire, whose experiments are so complex that multiple governments are helping fund it, whose conclusions are so counter-intuitive that the layman and the physicist are today many perspectives apart.
The second outcome is something I learnt while writing this post. The impetus that holds my two-decade-long learning spree up is nothing but fear, a fear of the unknown. Not learning something on a given day, with me, seems like forgoing a chance to imagine something we might not physically live. It's like the Copenhagen interpretation of quantum mechanics - a.k.a. Schrodinger's cat: for as long as I don't open the box, the cat is both dead and alive, the experience is both there and not there.
Saying "I learn not because I want to" is too bland: I learn because I want to look into the darkest corners of the universe and not see something that I can't understand or gauge in some way.
The popularly perceived notion of beauty comes with inexplicability: the capacity of an entity to defy definition and/or predictability, to defy structure and exhibit a will of its own in form and function. However, the silent reminder we are everyday given that, no matter how far out into the universe we venture or how deep we probe into the atom, the laws of physics are the same is the soul of beauty. And the inexplicability I seek to defy by learning is simply understanding how the same thing that gave us the dung beetle also gave us the Carina Nebula, that the same thing that gave us the Monarch butterfly also have us black holes.
[caption id="attachment_21625" align="aligncenter" width="335" caption="This image of the Carina Nebula is composed of multiple shots taken from the Atacama Desert in South America."]
[/caption]
I think that's a fear I've enjoyed and enjoy having.
The reason I remember the experience is that, more often than not, one doesn't know when the learning phase of life ends - many, like me, don't even know what comes after it if it ends. However, earlier today, when I was reading a journal article on using laser-induced plasma and the technology's application in particle accelerators, I surprised myself by understanding the entire thing without stopping even once; I could get what the authors were saying even when they were speaking only via formulae.
It was strangely dejecting because one of the most likeable things about particle physics in my opinion is its tendency to throw up previously unknown information just when we least expect it. In fact, even the one thing we thought we knew about this universe - the highest speed possible - was defied last year by some 15,000 neutrinos. And in such a scenario, when the picture suddenly becomes clear, when I can see the jigsaw puzzle board and the different empty shapes here and there waiting to be filled, it's as if I'm ready to start answering the bigger questions and leave the smaller ones behind.
[caption id="attachment_21624" align="aligncenter" width="334" caption="Clinton Davisson (left) and Lester Germer conducted an experiment since named after them - as the Davisson-Germer experiment - in 1927. Six years earlier, Einstein had won the Nobel Prize in physics for his discovery that particles were discrete encapsulations of energy called quanta. In 1927, French physicist Louis de Broglie presented his thesis that all particles have a wave-like characteristic. In the Davisson-Germer experiment, the two Americans stumbled across an electron diffraction pattern where they were expecting an electron diffuse-reflection pattern while studying the surface of nickel. This proved de Broglie's informed conjecture true."]
[/caption]I feel like the depressed man whose psychiatrist suggests he witness a performance by a clown in town. The depressed man then admits he is that clown.
At this point, I see two outcomes. The first one hints that I only want to keep learning and I'm not as interested in "deploying" that knowledge usefully. That is only partly true because, hey, I don't have a particle collider in my backyard that introduces new particles into my life so I can piece the universal puzzle together better. The second outcome suggests that my knowing a lot of things - science-wise and not - is, for the most part, a product of this fear of what-will-or-won't-come-next.
The first outcome doesn't bother me much because I've discovered I like teaching. Even though I may not be using my knowledge of IC engines to fix vehicles on desolate highways, I try and ensure as many people as possible understand how such engines work and do what they want with that knowledge. The same applies for particle physics. However, in this case, the dimension of teaching acquires more weight because its capacity to be misunderstood is great: it's a developing field whose foundations are currently under fire, whose experiments are so complex that multiple governments are helping fund it, whose conclusions are so counter-intuitive that the layman and the physicist are today many perspectives apart.
The second outcome is something I learnt while writing this post. The impetus that holds my two-decade-long learning spree up is nothing but fear, a fear of the unknown. Not learning something on a given day, with me, seems like forgoing a chance to imagine something we might not physically live. It's like the Copenhagen interpretation of quantum mechanics - a.k.a. Schrodinger's cat: for as long as I don't open the box, the cat is both dead and alive, the experience is both there and not there.
Saying "I learn not because I want to" is too bland: I learn because I want to look into the darkest corners of the universe and not see something that I can't understand or gauge in some way.
The popularly perceived notion of beauty comes with inexplicability: the capacity of an entity to defy definition and/or predictability, to defy structure and exhibit a will of its own in form and function. However, the silent reminder we are everyday given that, no matter how far out into the universe we venture or how deep we probe into the atom, the laws of physics are the same is the soul of beauty. And the inexplicability I seek to defy by learning is simply understanding how the same thing that gave us the dung beetle also gave us the Carina Nebula, that the same thing that gave us the Monarch butterfly also have us black holes.
[caption id="attachment_21625" align="aligncenter" width="335" caption="This image of the Carina Nebula is composed of multiple shots taken from the Atacama Desert in South America."]
[/caption]I think that's a fear I've enjoyed and enjoy having.
Tuesday, 31 January 2012
Strange test post
This is a test post.
All strange quarks, the third-lightest among quarks, have a spin of 1/2 by virtue of being fermions and a charge of -1/3 e. The particle itself holds the curious discintion of having been discovered (1947) before it was theorized (1964). The first observed particle that contained a strange quark was called a kaon.
Monday, 19 December 2011
Observing the God particle: An interview with Dr. G. Baskaran (translated from Tamil)
Note: The following telephone interview was broadcast by the BBC on the occasion of CERN’s announcement on December 13. The CERN announced that it had fairly conclusive data that confirmed the glimpsing of a Higgs boson in experiments conducted at the Large Hadron Collider. The interviewee, Dr. G. Baskaran, is a distinguished physicist currently engaged with research at the Perimeter Institute, Canada.
My comments appear in square brackets, [ ], and explain concepts that are required to understand Dr. Baskaran's answers. Statements spoken by the interviewer are marked with bold letters.
The audio of the interview is linked herewith: http://www.bbc.co.uk/emp/worldwide/player.swf
-Begin-
Interviewer: Before we begin a discussion on the Higgs boson, it is important to understand the background of this experiment. Physicists began the search for this particle with the belief that everything in this universe is composed of atoms, and atoms of nuclei. It was due to the contribution of technology that they were then able to break open the nuclei and enter it to find many new particles.
The consequential research has been going on for many years, and led to the formation of a cogent theory that could explain the behavior of all those particles. Physicists called this theory the Standard Model. As they began to work with it, they came across an important glitch: using just those particles that constituted the Standard Model, they couldn’t explain gravitation. Subsequently, physicists directed themselves to find a suitable solution, which took the form of the Higgs boson.
Just like mathematicians, when faced with a problem, use a variable ‘X’ in their equations so they can proceed with their calculations, particle physicists used the Higgs boson as their ‘X’ and proceeded with their unknotting of the universe’s riddles. Since this substitution, which happened in the 1960s, calculations have been going on relatively smoothly but the lack of knowledge of the Higgs’s properties remained elusive.
In this context: on December 13, scientists working at the CERN’s Large Hadron Collider announced that they may have glimpsed the Higgs boson during one of their experiments. When Dr. G. Baskaran, distinguished research chair at the Perimeter Institute in Canada and a Ramanna Fellow with the Institute of Mathematical Science, Chennai, was asked about this announcement, he had this to say: “The things we see in nature, the rocks and sand—as we delve deeper and deeper into them, we come across molecules and atoms. Inside these atoms, we have electrons—orbiting the nucleus—and protons and neutrons inside the nucleus.”
“These elementary particles cannot be seen by the naked eye but only by sophisticated instruments. These particles have been the foundation for a new theory. At such nanoscopic levels of observation, Newton’s laws fail and, instead, quantum theory comes to life. The physics for this theory dates back to almost a century, since the discovery of the electron by Thompson and Einstein’s baptism of photons as the carriers of electromagnetic waves.”
“It was observed that all these particles had mass, and with even more experiments, the values of those masses were found: the particles are very, very light, yes, but they did have a definite mass. So when you consider the mass of the photon, it is zero. The energy for the photon comes from its momentum: it travels at a very high speed. It is impossible to trap or localize a photon, and this has been verified by particle physicists.”
“Avvayyar [a Tamil poet] once spoke about breaking open a sea of particles only to flood seven oceans, and something similar has been happening in the quest for understanding these particles. For example, once physicists broke open the proton, they found quarks and gluons, and when quarks and gluons ‘reacted’, they found neutrinos. The field of physics that concerns itself with the smashing-discovering process is called high-energy physics.”
“Researchers soon realized that they couldn’t experiment with these smaller and smaller particles directly. Instead, they accelerated beams of such particles to high velocities and forced them to collide head-on. At that moment, like how two cars crash into each other and are shot to smithereens, the particles in the beam lose their consistency, break apart, and whatever particles are inside are liberated. Soon, high-energy physics branched out to yield accelerator physics, which deals only with the acceleration of particles to extreme speeds and energies.”
“When particles have an electric charge, placing them close to an electric field will either make the particles move toward or away from the field, in the process accelerating them. According to Albert Einstein, nothing can move faster than light (or photons) and so these particles are accelerated to close to 90-95 per cent the speed of light. When they collided at such speeds, the resulting spew of particles is sieved through to find the building blocks of matter.”
Where and how does the Higgs boson appear in this mesh of theories and particles?
“In the 20th century, great physicists like Dirac put together the theory of quantum electrodynamics (QED) to understand how particles and forces work together. QED assumes that particles like electrons have mass and that photons don’t. Subsequently, the question QED asks is why electrons have mass and photons don’t, and why so much mass and not some more or some less.”
“In the zoo of elementary particles—about 50 of them were assumed to exist by the time QED was formulated—a pattern was beginning to emerge when physicists attempted to answer the question. The pattern would eventually become the Standard Model, and in the meantime, physicists Abdus Salam, Steven Weinberg and Sheldon Glashow were awarded the Nobel Prize for their efforts in working the Model out. I knew Prof. Salam personally; now he is no more.”
“The trio’s principle contribution was a framework within which theories could be analyzed to determine how mass is generated. This framework worked with what are now called the Higgs field, the Higgs mechanism and the gauge bosons. The significance of their theory was that all those particles that were hypothesized by them were eventually observed in experimental setups. Everything but the Higgs boson.”
In all mathematical calculations up to this point, most predictions have been hinged on the possible existence of the Higgs boson. Therefore, it became important to look for this particularly.
“While the theory was successful, the significance of ‘sighting’ the particle kept growing. The boson—a moniker named for Satyendra Nath Bose—worked its magic in unseen ways, and that was frustrating. Now, the elementary particles are classified as bosons and fermions. Electrons, protons and neutrons are all fermions, and photons are bosons. The Higgs boson is what is called a scalar boson.”
[All particles have a property called spin that is one of the definers of their state in quantum physics. Fermions have fractional spin, like ½. Bosons, on the other hand, have integer spin, like 1 or 0. Any boson termed scalar will have a spin of 0.]
“Research in physics has revealed that the Higgs boson exists in a ‘rain of energy’, i.e. its energy is in the range of a hundred giga-electron volt (GeV). Once they set about combing for appearances of the Higgs boson in reactions that happened at such an energy level, however, they couldn’t find anything of relevance. In furtherance of this search, the Large Hadron Collider (LHC) was set up at the CERN in Europe. In an experiment conducted in this ultra-precise high-energy accelerator, scientists have claimed today that they have glimpsed the Higgs boson.”
“There is a fascinating correlation between the search for the Higgs boson and the question of why particles have mass, which was brought out by a physicist named Yoichiro Nambu who won the Nobel Prize in physics for it [in 2008]. Nambu’s theory explained the origin of mass using the phenomenon of BCS-superconductivity.”
[Named for John Bardeen, Leon Anderson Cooper and John Robert Schrieffer, the BCS theory explains that superconductivity is the result of electrons, in extremely cold temperatures, condensing into boson-like pairs, called Cooper pairs that cannot be “kicked” by the ambient temperature to resist the flow of electric current.]
“Nambu was inspired by Cooper’s idea of pairing to suggest that the two mechanisms—pair-generation and mass-generation—were similar. This is the beautiful thing about physics: two seemingly unrelated phenomena observed in fields conceptually far-apart will find kinship simply because physics is unbiased and unifying. Anyway, this similarity between the two mechanisms provides an alternate name for the Higgs boson: the Anderson-Higgs boson. Dr. [Phil] Anderson is a renowned man in physics, who currently works at Princeton university, and I have been collaborating with him since 1984.”
What will physics look like if the truth of the Higgs boson is cemented?
“In my opinion, it will only complete a chapter in the history of elementary particle physics and reopen the next chapter for study. Elementary particle physics requires many other theories to become fully explicable like, for instance, supersymmetry. According to supersymmetry—which Abdus Salam was also involved in—every fermion ought to have a boson counterpart. This means that the electron should have a corresponding electronic boson. However, such bosons are yet to be spotted. Their significance arises out of the possibility that such counterpart-bosons could be responsible for determining which particle has how much mass.”
“At the cutting edge of physics research, at which the LHC lies, one of the goals is to find these supersymmetric partners. Another is to find dimensions other than the four we engage with [length, breadth, depth and time]. Some physicists argue that there multi-dimensional systems of the order of 22 dimensions, whose signatures might pop up during experiments at the LHC.”
At the same time, the CERN announcement only claims a possibility of the Higgs boson’s existence, not a certainty. They also haven’t announced what conditions or phenomena will establish such a certainty. Why do you think this is so?
“The Higgs boson is extremely short-lived, i.e. the particle decays before instruments in the detectors can focus on it and record its properties. For example, an electron might escape detection by speeding away, sometimes it might decay under higher energies to smaller particles, but the electron will have remained an electron until the moment it ‘dies’, either by decaying or annihilating in the presence of a positron to yield a gamma ray.”
“An electron’s lifetime is very, very long. The lifetime of a Higgs boson, on the other hand, is very, very low. Therefore, the way to detect a Higgs boson is to look for the presence of its decay signature. A lot of errors can creep into the process of looking for this signature. This is why physicists, who are reluctant to commit that they’ve eliminated all errors, are also reluctant to claim that they’ve found the Higgs boson for sure.”
Interviewer: Dr. G. Baskaran, senior professor, Institute of Mathematical Science, Chennai
-End-
My comments appear in square brackets, [ ], and explain concepts that are required to understand Dr. Baskaran's answers. Statements spoken by the interviewer are marked with bold letters.
The audio of the interview is linked herewith: http://www.bbc.co.uk/emp/worldwide/player.swf
-Begin-
Interviewer: Before we begin a discussion on the Higgs boson, it is important to understand the background of this experiment. Physicists began the search for this particle with the belief that everything in this universe is composed of atoms, and atoms of nuclei. It was due to the contribution of technology that they were then able to break open the nuclei and enter it to find many new particles.
The consequential research has been going on for many years, and led to the formation of a cogent theory that could explain the behavior of all those particles. Physicists called this theory the Standard Model. As they began to work with it, they came across an important glitch: using just those particles that constituted the Standard Model, they couldn’t explain gravitation. Subsequently, physicists directed themselves to find a suitable solution, which took the form of the Higgs boson.
Just like mathematicians, when faced with a problem, use a variable ‘X’ in their equations so they can proceed with their calculations, particle physicists used the Higgs boson as their ‘X’ and proceeded with their unknotting of the universe’s riddles. Since this substitution, which happened in the 1960s, calculations have been going on relatively smoothly but the lack of knowledge of the Higgs’s properties remained elusive.
In this context: on December 13, scientists working at the CERN’s Large Hadron Collider announced that they may have glimpsed the Higgs boson during one of their experiments. When Dr. G. Baskaran, distinguished research chair at the Perimeter Institute in Canada and a Ramanna Fellow with the Institute of Mathematical Science, Chennai, was asked about this announcement, he had this to say: “The things we see in nature, the rocks and sand—as we delve deeper and deeper into them, we come across molecules and atoms. Inside these atoms, we have electrons—orbiting the nucleus—and protons and neutrons inside the nucleus.”
“These elementary particles cannot be seen by the naked eye but only by sophisticated instruments. These particles have been the foundation for a new theory. At such nanoscopic levels of observation, Newton’s laws fail and, instead, quantum theory comes to life. The physics for this theory dates back to almost a century, since the discovery of the electron by Thompson and Einstein’s baptism of photons as the carriers of electromagnetic waves.”
“It was observed that all these particles had mass, and with even more experiments, the values of those masses were found: the particles are very, very light, yes, but they did have a definite mass. So when you consider the mass of the photon, it is zero. The energy for the photon comes from its momentum: it travels at a very high speed. It is impossible to trap or localize a photon, and this has been verified by particle physicists.”
“Avvayyar [a Tamil poet] once spoke about breaking open a sea of particles only to flood seven oceans, and something similar has been happening in the quest for understanding these particles. For example, once physicists broke open the proton, they found quarks and gluons, and when quarks and gluons ‘reacted’, they found neutrinos. The field of physics that concerns itself with the smashing-discovering process is called high-energy physics.”
“Researchers soon realized that they couldn’t experiment with these smaller and smaller particles directly. Instead, they accelerated beams of such particles to high velocities and forced them to collide head-on. At that moment, like how two cars crash into each other and are shot to smithereens, the particles in the beam lose their consistency, break apart, and whatever particles are inside are liberated. Soon, high-energy physics branched out to yield accelerator physics, which deals only with the acceleration of particles to extreme speeds and energies.”
“When particles have an electric charge, placing them close to an electric field will either make the particles move toward or away from the field, in the process accelerating them. According to Albert Einstein, nothing can move faster than light (or photons) and so these particles are accelerated to close to 90-95 per cent the speed of light. When they collided at such speeds, the resulting spew of particles is sieved through to find the building blocks of matter.”
Where and how does the Higgs boson appear in this mesh of theories and particles?
“In the 20th century, great physicists like Dirac put together the theory of quantum electrodynamics (QED) to understand how particles and forces work together. QED assumes that particles like electrons have mass and that photons don’t. Subsequently, the question QED asks is why electrons have mass and photons don’t, and why so much mass and not some more or some less.”
“In the zoo of elementary particles—about 50 of them were assumed to exist by the time QED was formulated—a pattern was beginning to emerge when physicists attempted to answer the question. The pattern would eventually become the Standard Model, and in the meantime, physicists Abdus Salam, Steven Weinberg and Sheldon Glashow were awarded the Nobel Prize for their efforts in working the Model out. I knew Prof. Salam personally; now he is no more.”
“The trio’s principle contribution was a framework within which theories could be analyzed to determine how mass is generated. This framework worked with what are now called the Higgs field, the Higgs mechanism and the gauge bosons. The significance of their theory was that all those particles that were hypothesized by them were eventually observed in experimental setups. Everything but the Higgs boson.”
In all mathematical calculations up to this point, most predictions have been hinged on the possible existence of the Higgs boson. Therefore, it became important to look for this particularly.
“While the theory was successful, the significance of ‘sighting’ the particle kept growing. The boson—a moniker named for Satyendra Nath Bose—worked its magic in unseen ways, and that was frustrating. Now, the elementary particles are classified as bosons and fermions. Electrons, protons and neutrons are all fermions, and photons are bosons. The Higgs boson is what is called a scalar boson.”
[All particles have a property called spin that is one of the definers of their state in quantum physics. Fermions have fractional spin, like ½. Bosons, on the other hand, have integer spin, like 1 or 0. Any boson termed scalar will have a spin of 0.]
“Research in physics has revealed that the Higgs boson exists in a ‘rain of energy’, i.e. its energy is in the range of a hundred giga-electron volt (GeV). Once they set about combing for appearances of the Higgs boson in reactions that happened at such an energy level, however, they couldn’t find anything of relevance. In furtherance of this search, the Large Hadron Collider (LHC) was set up at the CERN in Europe. In an experiment conducted in this ultra-precise high-energy accelerator, scientists have claimed today that they have glimpsed the Higgs boson.”
“There is a fascinating correlation between the search for the Higgs boson and the question of why particles have mass, which was brought out by a physicist named Yoichiro Nambu who won the Nobel Prize in physics for it [in 2008]. Nambu’s theory explained the origin of mass using the phenomenon of BCS-superconductivity.”
[Named for John Bardeen, Leon Anderson Cooper and John Robert Schrieffer, the BCS theory explains that superconductivity is the result of electrons, in extremely cold temperatures, condensing into boson-like pairs, called Cooper pairs that cannot be “kicked” by the ambient temperature to resist the flow of electric current.]
“Nambu was inspired by Cooper’s idea of pairing to suggest that the two mechanisms—pair-generation and mass-generation—were similar. This is the beautiful thing about physics: two seemingly unrelated phenomena observed in fields conceptually far-apart will find kinship simply because physics is unbiased and unifying. Anyway, this similarity between the two mechanisms provides an alternate name for the Higgs boson: the Anderson-Higgs boson. Dr. [Phil] Anderson is a renowned man in physics, who currently works at Princeton university, and I have been collaborating with him since 1984.”
What will physics look like if the truth of the Higgs boson is cemented?
“In my opinion, it will only complete a chapter in the history of elementary particle physics and reopen the next chapter for study. Elementary particle physics requires many other theories to become fully explicable like, for instance, supersymmetry. According to supersymmetry—which Abdus Salam was also involved in—every fermion ought to have a boson counterpart. This means that the electron should have a corresponding electronic boson. However, such bosons are yet to be spotted. Their significance arises out of the possibility that such counterpart-bosons could be responsible for determining which particle has how much mass.”
“At the cutting edge of physics research, at which the LHC lies, one of the goals is to find these supersymmetric partners. Another is to find dimensions other than the four we engage with [length, breadth, depth and time]. Some physicists argue that there multi-dimensional systems of the order of 22 dimensions, whose signatures might pop up during experiments at the LHC.”
At the same time, the CERN announcement only claims a possibility of the Higgs boson’s existence, not a certainty. They also haven’t announced what conditions or phenomena will establish such a certainty. Why do you think this is so?
“The Higgs boson is extremely short-lived, i.e. the particle decays before instruments in the detectors can focus on it and record its properties. For example, an electron might escape detection by speeding away, sometimes it might decay under higher energies to smaller particles, but the electron will have remained an electron until the moment it ‘dies’, either by decaying or annihilating in the presence of a positron to yield a gamma ray.”
“An electron’s lifetime is very, very long. The lifetime of a Higgs boson, on the other hand, is very, very low. Therefore, the way to detect a Higgs boson is to look for the presence of its decay signature. A lot of errors can creep into the process of looking for this signature. This is why physicists, who are reluctant to commit that they’ve eliminated all errors, are also reluctant to claim that they’ve found the Higgs boson for sure.”
Interviewer: Dr. G. Baskaran, senior professor, Institute of Mathematical Science, Chennai
-End-
Monday, 12 December 2011
Sailing the intergalactic pea soup
It's really hard for many people to get excited about the impending announcement by CERN concerning the search for the Higgs boson (or the 'God' particle). The only reason I'm following it is because I'm interested in nuclear physics and the prospect of having the Higgs mechanism validated excites me. While I believe that any more-conclusive words on the subject will have a great impact on the future of science and scientific research, my colleagues in journalism think it is just another event, a yet-another-small-discovery that further cements our understanding of the universe.
[caption id="attachment_20955" align="aligncenter" width="530" caption="The ATLAS (A Toroidal LHC ApparatuS), above, and the CMS (Compact Muon Solenoid) are two general-purpose detectors on the Large Hadron collider. They gathered the hundreds of thousands of gigabytes of data that scientists are sifting through looking for signs of the Higgs boson."]
[/caption]
[caption id="attachment_20956" align="aligncenter" width="483" caption="The Compact Muon Solenoid (CMS)"]
[/caption]
At the same time, political and sports stories find purchase just about as soon as they transpire and from almost all quarters they reach to. That science lacks the same hold has been the subject of many a technical discourse in the past. Even more: given how we're in the golden age of science journalism, many of today's stories, if not all, do a much better job of making people understand why and how science is important irrespective of their academic backgrounds. But even now, our progress is slow and difficult. In this context, as we enter an era of physics even more elegant in its complexity, an era of science as such that finally thinks itself in a position to explain everything that it encounters, journalists have an opportunity.
Windows such as this don't open often because the windows that do don't have the sort of significance and import that will get them on the front-page, that will secure them the modicum of attention required to sustain enough attention in the matter to draw questions and more interest from readers.
When Albert Einstein formulated the general and special theories of relativity, it was the beginning of a fascinating time for physics and chemistry: finally, something had been put in place that was robust and did not succumb to any probing thought experiment it was subjected to. Even though it pushed what it couldn't explain to the fringes of phenomenology, it was just as good because it consistently explained everything that we had observed and could observe - all the way from the smallest particles to the largest stars. Also the discoverer of the photoelectric effect that eventually lead to the packaging of the Standard Model, Einstein provided invaluable focus to a subject many until then couldn't comfortably approach.
[caption id="attachment_20957" align="aligncenter" width="436" caption="Particles postulated by the Standard Model of particle physics"]
[/caption]
In other words, tomorrow's announcement will reveal the picture that Einstein and his successors jotted out the dots for. A definite "Yes" will seal the deal for particle physicists and provide them with the foundation necessary to explore the nature of dark matter and the origins of the universe. A definite "No" will send them scurrying back to their notes and prompt a critical scrutiny of what went wrong and how it can be fixed.
I believe that there can be not many other moments that will possess the same significance as the propsect of finding the Higgs boson presents. In fact, even its invalidation will be just as good because it will debunk the simple Higgs mechanism and force reconsideration.
[caption id="attachment_20958" align="alignleft" width="240" caption="The Higgs mechanism"]
[/caption]
Simply, the Higgs boson is the protagonist in the play of particles that imparts mass to everything in this universe. To understand the mechanism with which it imparts mass, there is the oft-quoted example of a famous movie star walking into a crowded room. As he enters through the door, he gathers a group around him that slows him down in his journey through the room. The group moves with him: those he leaves behind melt away while those he moves toward come forward. Finally, when he exits the room, the group disappears, too, and the room is just crowded once more. Similarly, the Higgs boson creates a charged field around it. When particles move through this field, they acquire some mass that slows them down accordingly.
There are only a few unexplained "mysteries" in the realm of physics. The more famous amongst them are the source of gravitational forces - accounted for by the hypothetical Higgs mechanism - and the nature of dark matter. The 2011 Nobel Prize for physics was awarded to Saul Perlmutter, an astrophysicist who proved that galaxies are moving farther apart not at decelerating or constant speeds but at increasing rates. This means that after the initial blow of the Big Bang, something is pushing the galaxies farther faster, and this something has been hypothesized to be dark matter.
[caption id="attachment_20960" align="aligncenter" width="475" caption="The frontiers of physics"]
[/caption]
Reporting such stories is going to be different from reporting other stories because this is a frontier of physics, where it is easy to trip and fall, difficult to pick oneself back up and where almost nothing is certain. At the cutting edge, the byword has to be caution more than anything else, including interest and adventure, because of two reasons.
An interview of physicist and recent author Lisa Randall by The New York Times illustrates this seldom exercised caution in such matters by many journalists reporting the issue.
Because of its notoriously elusive nature, the search for the Higgs boson has acquired an anthemic proportion which makes it easier for the story to be reported when the more arduous aspects of it are filtered out. It makes journalistic capitalization more accessible, which will push the twin notions of ethical science reporting and essential science reporting further apart. And where ethical science reporting accounts for the trust between the writer and the reader, essential science reporting accounts for what stories are important and therefore must be covered.
[caption id="attachment_20961" align="aligncenter" width="520" caption="Using "Don't you know who I am!" to define right and wrong where they haven't been defined can a dangerous thing."]
[/caption]
Breaking a science story just because it happened somewhere and presents news-like information to a local group is not the duty of a journalist. The duty is to inform his/her readers which piece of news is more important and why. Unlike other subjects that are reported, science journalists don't have the liberty of drawing from a repetitive history to forecast the future. They can never possess the intellectual resources necessary to influence readers to repeat the past. In taking anyone forward, science journalists must guide with both the direction of each step and the distance it covers.
When the time does come for the revelation that it won't be another year before the verifications are all complete, many people will have lost interest in the subject because what they thought would've mattered to them would've happened a year ago. Instead of creating false reasons to celebrate the findings just because nobody is noticing, reporters must undertake a sustained coverage of important issues. If they don't - if we don't - then it's going to become very hard to get readers to catch up with what's going on.
[caption id="attachment_20962" align="aligncenter" width="530" caption="Context is important: it sets the tone of the story as well as determines where we're headed to."]
[/caption]
As the search for the Higgs boson nears an important milestone, the interactive forces within the field highlight the importance of focusing stories on the ancillary qualities of the scientific method instead of the phenomena born thereof. For those for whom scientific principles don't mean much, for those whose readership I, the journalist, require and need to cultivate, stories with misconstructed contexts will work against my intention to bridge the gap between research and technology. Like the following anonymous quote implies,
Not telling the reader something he doesn't know exists can be used both to preserve a narrow context where it may be necessary to keep away confusion and to secure personal interests and not risk public interference in the matter. The former is difficult to use, the latter is just wrong. We must carefully introduce, sustain and finish as does science: with "systematic observation, measurement, and experiment, and the formulation, testing and the modification of hypotheses."
[caption id="attachment_20955" align="aligncenter" width="530" caption="The ATLAS (A Toroidal LHC ApparatuS), above, and the CMS (Compact Muon Solenoid) are two general-purpose detectors on the Large Hadron collider. They gathered the hundreds of thousands of gigabytes of data that scientists are sifting through looking for signs of the Higgs boson."]
[/caption][caption id="attachment_20956" align="aligncenter" width="483" caption="The Compact Muon Solenoid (CMS)"]
[/caption]At the same time, political and sports stories find purchase just about as soon as they transpire and from almost all quarters they reach to. That science lacks the same hold has been the subject of many a technical discourse in the past. Even more: given how we're in the golden age of science journalism, many of today's stories, if not all, do a much better job of making people understand why and how science is important irrespective of their academic backgrounds. But even now, our progress is slow and difficult. In this context, as we enter an era of physics even more elegant in its complexity, an era of science as such that finally thinks itself in a position to explain everything that it encounters, journalists have an opportunity.
Windows such as this don't open often because the windows that do don't have the sort of significance and import that will get them on the front-page, that will secure them the modicum of attention required to sustain enough attention in the matter to draw questions and more interest from readers.
When Albert Einstein formulated the general and special theories of relativity, it was the beginning of a fascinating time for physics and chemistry: finally, something had been put in place that was robust and did not succumb to any probing thought experiment it was subjected to. Even though it pushed what it couldn't explain to the fringes of phenomenology, it was just as good because it consistently explained everything that we had observed and could observe - all the way from the smallest particles to the largest stars. Also the discoverer of the photoelectric effect that eventually lead to the packaging of the Standard Model, Einstein provided invaluable focus to a subject many until then couldn't comfortably approach.
[caption id="attachment_20957" align="aligncenter" width="436" caption="Particles postulated by the Standard Model of particle physics"]
[/caption]In other words, tomorrow's announcement will reveal the picture that Einstein and his successors jotted out the dots for. A definite "Yes" will seal the deal for particle physicists and provide them with the foundation necessary to explore the nature of dark matter and the origins of the universe. A definite "No" will send them scurrying back to their notes and prompt a critical scrutiny of what went wrong and how it can be fixed.
I believe that there can be not many other moments that will possess the same significance as the propsect of finding the Higgs boson presents. In fact, even its invalidation will be just as good because it will debunk the simple Higgs mechanism and force reconsideration.
[caption id="attachment_20958" align="alignleft" width="240" caption="The Higgs mechanism"]
[/caption]Simply, the Higgs boson is the protagonist in the play of particles that imparts mass to everything in this universe. To understand the mechanism with which it imparts mass, there is the oft-quoted example of a famous movie star walking into a crowded room. As he enters through the door, he gathers a group around him that slows him down in his journey through the room. The group moves with him: those he leaves behind melt away while those he moves toward come forward. Finally, when he exits the room, the group disappears, too, and the room is just crowded once more. Similarly, the Higgs boson creates a charged field around it. When particles move through this field, they acquire some mass that slows them down accordingly.
There are only a few unexplained "mysteries" in the realm of physics. The more famous amongst them are the source of gravitational forces - accounted for by the hypothetical Higgs mechanism - and the nature of dark matter. The 2011 Nobel Prize for physics was awarded to Saul Perlmutter, an astrophysicist who proved that galaxies are moving farther apart not at decelerating or constant speeds but at increasing rates. This means that after the initial blow of the Big Bang, something is pushing the galaxies farther faster, and this something has been hypothesized to be dark matter.
[caption id="attachment_20960" align="aligncenter" width="475" caption="The frontiers of physics"]
[/caption]Reporting such stories is going to be different from reporting other stories because this is a frontier of physics, where it is easy to trip and fall, difficult to pick oneself back up and where almost nothing is certain. At the cutting edge, the byword has to be caution more than anything else, including interest and adventure, because of two reasons.
- Physics at the cutting-edge is inaccessible to almost everyone who's not at CERN or some other high-tech lab. In such a case, misrepresentation is misguidance magnified by the unfortunate inaccessibility.
- The farther we move into uncharted territories, into the "intergalactic atomic pea soup" as it were, the more we're assuming holds true. Think of this as a sailor who has lost his way in the sea but providentially happens to have tied his boat to a safe harbour by means of a very long rope. As he moves farther away from that harbour, the more rope he will spend in between, and more is the rope he will have to account for that has not been cut.
An interview of physicist and recent author Lisa Randall by The New York Times illustrates this seldom exercised caution in such matters by many journalists reporting the issue.
Q. What do we know about it so far?
A. Experimenters have already ruled out a large range of masses. The Higgs boson, if it exists, has to be heavier than 114.4 giga-electron volts (GeV), which are the units of mass that particle physicists use. By comparison, protons, the bedrock of ordinary matter, are about 1 giga-electron volt, and an electron is only half a million electron volts.
Based on recent searches by the L.H.C., the Higgs boson is also excluded between about 140 GeV and 500 GeV. This makes the most likely region for the Higgs mass to be between about 115 and 140 GeV, which is the range Tuesday’s results should focus on, although in principle heavier Higgs boson masses are in contention too.
I don’t want to shatter hopes, but don’t count on Tuesday’s results being definitive. This is the toughest range of masses for the L.H.C., and detection is tricky for this range. I suspect they will have enough evidence not to exclude the Higgs, but too little to fully pin it down without next year’s data.
Because of its notoriously elusive nature, the search for the Higgs boson has acquired an anthemic proportion which makes it easier for the story to be reported when the more arduous aspects of it are filtered out. It makes journalistic capitalization more accessible, which will push the twin notions of ethical science reporting and essential science reporting further apart. And where ethical science reporting accounts for the trust between the writer and the reader, essential science reporting accounts for what stories are important and therefore must be covered.
[caption id="attachment_20961" align="aligncenter" width="520" caption="Using "Don't you know who I am!" to define right and wrong where they haven't been defined can a dangerous thing."]
[/caption]Breaking a science story just because it happened somewhere and presents news-like information to a local group is not the duty of a journalist. The duty is to inform his/her readers which piece of news is more important and why. Unlike other subjects that are reported, science journalists don't have the liberty of drawing from a repetitive history to forecast the future. They can never possess the intellectual resources necessary to influence readers to repeat the past. In taking anyone forward, science journalists must guide with both the direction of each step and the distance it covers.
When the time does come for the revelation that it won't be another year before the verifications are all complete, many people will have lost interest in the subject because what they thought would've mattered to them would've happened a year ago. Instead of creating false reasons to celebrate the findings just because nobody is noticing, reporters must undertake a sustained coverage of important issues. If they don't - if we don't - then it's going to become very hard to get readers to catch up with what's going on.
[caption id="attachment_20962" align="aligncenter" width="530" caption="Context is important: it sets the tone of the story as well as determines where we're headed to."]
[/caption]As the search for the Higgs boson nears an important milestone, the interactive forces within the field highlight the importance of focusing stories on the ancillary qualities of the scientific method instead of the phenomena born thereof. For those for whom scientific principles don't mean much, for those whose readership I, the journalist, require and need to cultivate, stories with misconstructed contexts will work against my intention to bridge the gap between research and technology. Like the following anonymous quote implies,
The eye cannot see what the mind does not know
Not telling the reader something he doesn't know exists can be used both to preserve a narrow context where it may be necessary to keep away confusion and to secure personal interests and not risk public interference in the matter. The former is difficult to use, the latter is just wrong. We must carefully introduce, sustain and finish as does science: with "systematic observation, measurement, and experiment, and the formulation, testing and the modification of hypotheses."
Friday, 9 December 2011
Looks like we're getting somewhere.
On December 13, scientists working at the Large Hadron Collider (LHC) will make an important announcement. After the emergence of consistent information regarding two independent events at the ATLAS and CMS detectors, physicists at the sophisticated lab are excited because they may or may not have stumbled upon the elusive Higgs boson. Both events in the detectors showed a particle with mass corresponding to 125 billion electron volts that quickly decayed with a curious radiation pattern: both the signature of a Higgs boson particle. Perhaps the only reason—and an important one—is that the finding doesn't conform to the five-sigma statistical tolerance limit: reportedly, the result is 3.5 or 4.5 sigma, giving it a whopping 1-in-370 chance of being a false positive.
Looks like we're getting somewhere.
On December 13, scientists working at the Large Hadron Collider (LHC) will make an important announcement. After the emergence of consistent information regarding two independent events at the ATLAS and CMS detectors, physicists at the sophisticated lab are excited because they may or may not have stumbled upon the elusive Higgs boson. Both events in the detectors showed a particle with mass corresponding to 125 billion electron volts that quickly decayed with a curious radiation pattern: both the signature of a Higgs boson particle. Perhaps the only reason—and an important one—that stakeholders are being circumspect is that the finding doesn't conform to the five-sigma statistical tolerance limit: reportedly, the result is 3.5 or 4.5 sigma, giving it a whopping 1-in-370 chance of being a false positive.
Monday, 21 November 2011
When a certain sphere paid a visit
On September 27, 2011, when an innocuous neutrino started its short journey from the Large Hadron Collider in CERN on the Franco-Swiss border, the world rested comfortably on the shoulders of a certain Albert Einstein. The Universe tottered on the verge of becoming completely explicable, string theorists were retreating into the shadows whence they had come, and particle physicists did what they always have done: relax and wait for more results to prove them more right.
That neutrino proved them wrong. Even though all it did was beat a ray of light by 60 nanoseconds, it had managed to defy a lifetime’s work in physics by a physicist everyone considered the greatest of all time. By travelling faster than light, it had utterly disproved the monumental theory of relativity. Suddenly, things began to turn around: the Universe was suddenly shrouded in mystery, the space-time continuum was being re-examined, particle physicists began to doubt their education… and the string theorist was suddenly in the limelight.
What does this have to do with a book on Victorian sociology? Almost everything. Rewind back to 1884, when the schoolmaster of the small Philological School in Marylebone, Edwin Abbott Abbott, published a novella called Flatland: A Romance of Many Dimensions. The book was about a fictitious world inhabited by two-dimensional people, rather two-dimensional shapes that represented people: women were straight lines and men were polygons. It was a satire that mocked the Victorian way of life. Women were line-segments and therefore essentially one-dimensional, as was reflected by the limited roles they were allowed to play in the society. Men, on the other hand, had many sides to them, and therefore dominated the two-dimensional world.
[caption id="attachment_20765" align="aligncenter" width="370" caption="Flatland: A Romance of Many Dimensions, 1884"]
[/caption]
When, one day, a nameless sphere decides to pay a visit to the narrator, a humble square, it is unable to convince him of the existence of the third dimension. However, after the square is chosen as an apostle to taken to Spaceland, the three-dimensional world, he is convinced that solids exist. Upon his return, again, he is condemned in Flatland as a madman and nobody is inclined to take him seriously.
The book is a powerful allegory in that it describes with an oft-sardonic mathematical simplicity the plight of those who perpetuate prejudices and yet suffer from the prejudice of others. The plot itself is linear, unassuming and provides the reader with no distractions but only the thrill of a Kafkaesque fantasy. The nameless sphere and his divine visitations, the humble square and his naïve suppositions, even the monarch of Pointland and his solipsistic musings – all touch close to the everyman’s experiences.
In fact, were Flatland to be mired in reality at the outset by the author himself, the book would long have lost its charmingly experimental texture, condemned to spend its life like its narrator did. No; in being the only known work of mathematical fiction, the book has managed to survive more than a century of tireless scrutiny by portraying itself as an examination of dimensions and nothing more.
While Abbott himself could not have imagined its scope when he wrote it, the morals of Flatland were soon found to be applicable in a variety of settings, including those of the string theorist. Imagine his plight as he attempted desperately to convince his colleagues of the existence of 10, 18, even 23 dimensions, but failed miserably each time. Imagine, then, his exclamation when a certain sphere paid the particle physicists a visit.
It is not known whether Abbott was writing as a historian or as a misogynist: both roles become evident in the literature as the realm’s women, being lines, have to survive many ignominies, some metaphorical, some plainly derisive, to coexist with the freer men. However, such analyses can today safely be sidelined: Abbott’s views on feminism are hardly considered as such, whereas his prophetic insight into the role of time as a fourth dimension was considered by Einstein himself to be an inspiration. And to think the book that spelled the rise of the particle physicist also has come to spell the rise of the string theorist!
That neutrino proved them wrong. Even though all it did was beat a ray of light by 60 nanoseconds, it had managed to defy a lifetime’s work in physics by a physicist everyone considered the greatest of all time. By travelling faster than light, it had utterly disproved the monumental theory of relativity. Suddenly, things began to turn around: the Universe was suddenly shrouded in mystery, the space-time continuum was being re-examined, particle physicists began to doubt their education… and the string theorist was suddenly in the limelight.
What does this have to do with a book on Victorian sociology? Almost everything. Rewind back to 1884, when the schoolmaster of the small Philological School in Marylebone, Edwin Abbott Abbott, published a novella called Flatland: A Romance of Many Dimensions. The book was about a fictitious world inhabited by two-dimensional people, rather two-dimensional shapes that represented people: women were straight lines and men were polygons. It was a satire that mocked the Victorian way of life. Women were line-segments and therefore essentially one-dimensional, as was reflected by the limited roles they were allowed to play in the society. Men, on the other hand, had many sides to them, and therefore dominated the two-dimensional world.
[caption id="attachment_20765" align="aligncenter" width="370" caption="Flatland: A Romance of Many Dimensions, 1884"]
[/caption]When, one day, a nameless sphere decides to pay a visit to the narrator, a humble square, it is unable to convince him of the existence of the third dimension. However, after the square is chosen as an apostle to taken to Spaceland, the three-dimensional world, he is convinced that solids exist. Upon his return, again, he is condemned in Flatland as a madman and nobody is inclined to take him seriously.
The book is a powerful allegory in that it describes with an oft-sardonic mathematical simplicity the plight of those who perpetuate prejudices and yet suffer from the prejudice of others. The plot itself is linear, unassuming and provides the reader with no distractions but only the thrill of a Kafkaesque fantasy. The nameless sphere and his divine visitations, the humble square and his naïve suppositions, even the monarch of Pointland and his solipsistic musings – all touch close to the everyman’s experiences.
In fact, were Flatland to be mired in reality at the outset by the author himself, the book would long have lost its charmingly experimental texture, condemned to spend its life like its narrator did. No; in being the only known work of mathematical fiction, the book has managed to survive more than a century of tireless scrutiny by portraying itself as an examination of dimensions and nothing more.
While Abbott himself could not have imagined its scope when he wrote it, the morals of Flatland were soon found to be applicable in a variety of settings, including those of the string theorist. Imagine his plight as he attempted desperately to convince his colleagues of the existence of 10, 18, even 23 dimensions, but failed miserably each time. Imagine, then, his exclamation when a certain sphere paid the particle physicists a visit.
It is not known whether Abbott was writing as a historian or as a misogynist: both roles become evident in the literature as the realm’s women, being lines, have to survive many ignominies, some metaphorical, some plainly derisive, to coexist with the freer men. However, such analyses can today safely be sidelined: Abbott’s views on feminism are hardly considered as such, whereas his prophetic insight into the role of time as a fourth dimension was considered by Einstein himself to be an inspiration. And to think the book that spelled the rise of the particle physicist also has come to spell the rise of the string theorist!
Wednesday, 19 October 2011
Star of the Orient
India’s first particle physics observatory is to be constructed in the district of Theni in Tamil Nadu at an expense of Rs. 1,200 crore (USD 250 million). Called the India-based Neutrino Observatory (INO), the entire experiment will be situated 1.3 km under a hill to keep other radiations and cosmic rays from interfering with the study. This is because the neutrinos that the detector will be studying rarely interact with matter and pass through it at the rate of three or four interactions per nearly 85 trillion trillion trillion. The gouging of a tunnel 7m wide and 1.9km long for accessing the cavern that will house the systems was commenced on October 14, Friday, and is expected to take a year.
Twenty-seven days ago, a startling discovery set off tremors across the scientific community when the Gran Sasso National Laboratory inItalyreported that certain fundamental particles called neutrinos had been observed moving faster than light. The reason this observation caused such dissonance and a flurry of excitement is that, according to the physics megagiant Albert Einstein, the Universe would allow nothing to travel faster than light.
Then again, conclusive proof was not presented by the physicists at the lab—at least, not anything that was within the infamous six-sigma accuracy tolerance limit: 99.99999 per cent. It was little surprise, then, that within a week of the report, engineers were working in full-swing atJapan's Kamioka reactor, at theUSA's dreaded Fermilab, at the Sudbury Neutrino Observatory inCanada, to recreate the conditions at Gran Sasso. Far away, in India, a country that had until then been the principle centre for processing second-hand information, a 22-year old plan was finally being mobilized.
With just a 29-year old history, the energy frontier of physics research was supposed to last at least until 2018—the year of the Super Large Hadron Collider. With such unprecedented discoveries, however, a shift away from high-energy research and toward ultra-rare processes has become conspicuous. For the INO, the timing couldn’t have been better.
The decision to locate the observatory at Theni was finalized after evaluating the local topography, seismic stability, environmental disturbance, rock quality, availability of electricity and water, and rain patterns. In order to further minimize the impact of the project’s logistical and infrastructural operations, an extant but little-used road is being re-laid for the trucks and earthmovers to use, instead of having them move through five villages.
Funded by the government of India and the Tata Institute of Fundamental Research (TIFR), and coordinated by the Institute of Mathematical Sciences (IMS), the INO will host a supersensitive static detector called the Iron Calorimeter (ICAL), incorporating a magnet exactly four times as large as the one in use at the Large Hadron Collider. Such an effort will involve the INO-industry interface in a big way, drawing heavily on available industrial infrastructure, in issues related to mechanical structure, electronics and detector-related technology.
The detector will consist of a stack of alternating plates of iron and borosilicate glass, each totally numbering 30,000 and measuring 12m to a side. The glass plates, in turn, will consist of glass sheets with a noble gas sandwiched in between—an arrangement referred to collectively as a resistive plate chamber (RPC). When a neutrino interacts with iron, it will knock out an electron from its orbit around an atom and send it into the RPC. Once there, the electron will be picked up by positively charged electrodes sewn into the glass, translated into a signal, and sent to the data processors.
The source of the neutrinos will be the sun, supernovae, cosmic rays and other intergalactic phenomena, and the output will correspond to the particle’s mass, position of interaction, velocity, type, degree of oscillation and charge.
There are two reasons the INO stands out from its peers: the first is that the ICAL is going to be devoted to studying neutrinos and neutrinos only, and the second is that the ICAL will study them continuously without stopping (except for scheduled maintenance). Because of such principled and technical dedication, physicists expect the detector to shine light on some of the more elusive characteristics of neutrinos, such as flavour oscillations and neutrino-neutrino interactions.
These are boom times for Indian science. The national spending on science and technology has gone up in the last five years and is inching towards two per cent ofIndia's GDP. Hordes of new institutes are coming up in the nook and corner of the country—30 new central universities, 5 new Indian Institutes of Science Education and Research, 8 new Indian Institutes of Technology and 20 new Indian Institutes of Information Technology are in various stages of conception and completion.
However, simply increasing the number of institutes will not lead to better scientific prowess. The education system needs a complete rethink in order to attract more students to science and produce world class scientists (the last home-grown scientist to win a Nobel Prize was Sir C. V. Raman in 1930). In this direction, the INO is a giant leap forward because of its capacity to sustain research in subjects at the energy and cosmic frontiers, because of the special and exotic experimentation environments it will support, and because of the invaluable access it will provide to the Indian scientific community to cutting-edge information.
Twenty-seven days ago, a startling discovery set off tremors across the scientific community when the Gran Sasso National Laboratory inItalyreported that certain fundamental particles called neutrinos had been observed moving faster than light. The reason this observation caused such dissonance and a flurry of excitement is that, according to the physics megagiant Albert Einstein, the Universe would allow nothing to travel faster than light.
Then again, conclusive proof was not presented by the physicists at the lab—at least, not anything that was within the infamous six-sigma accuracy tolerance limit: 99.99999 per cent. It was little surprise, then, that within a week of the report, engineers were working in full-swing atJapan's Kamioka reactor, at theUSA's dreaded Fermilab, at the Sudbury Neutrino Observatory inCanada, to recreate the conditions at Gran Sasso. Far away, in India, a country that had until then been the principle centre for processing second-hand information, a 22-year old plan was finally being mobilized.
With just a 29-year old history, the energy frontier of physics research was supposed to last at least until 2018—the year of the Super Large Hadron Collider. With such unprecedented discoveries, however, a shift away from high-energy research and toward ultra-rare processes has become conspicuous. For the INO, the timing couldn’t have been better.
The decision to locate the observatory at Theni was finalized after evaluating the local topography, seismic stability, environmental disturbance, rock quality, availability of electricity and water, and rain patterns. In order to further minimize the impact of the project’s logistical and infrastructural operations, an extant but little-used road is being re-laid for the trucks and earthmovers to use, instead of having them move through five villages.
Funded by the government of India and the Tata Institute of Fundamental Research (TIFR), and coordinated by the Institute of Mathematical Sciences (IMS), the INO will host a supersensitive static detector called the Iron Calorimeter (ICAL), incorporating a magnet exactly four times as large as the one in use at the Large Hadron Collider. Such an effort will involve the INO-industry interface in a big way, drawing heavily on available industrial infrastructure, in issues related to mechanical structure, electronics and detector-related technology.
The detector will consist of a stack of alternating plates of iron and borosilicate glass, each totally numbering 30,000 and measuring 12m to a side. The glass plates, in turn, will consist of glass sheets with a noble gas sandwiched in between—an arrangement referred to collectively as a resistive plate chamber (RPC). When a neutrino interacts with iron, it will knock out an electron from its orbit around an atom and send it into the RPC. Once there, the electron will be picked up by positively charged electrodes sewn into the glass, translated into a signal, and sent to the data processors.
The source of the neutrinos will be the sun, supernovae, cosmic rays and other intergalactic phenomena, and the output will correspond to the particle’s mass, position of interaction, velocity, type, degree of oscillation and charge.
There are two reasons the INO stands out from its peers: the first is that the ICAL is going to be devoted to studying neutrinos and neutrinos only, and the second is that the ICAL will study them continuously without stopping (except for scheduled maintenance). Because of such principled and technical dedication, physicists expect the detector to shine light on some of the more elusive characteristics of neutrinos, such as flavour oscillations and neutrino-neutrino interactions.
These are boom times for Indian science. The national spending on science and technology has gone up in the last five years and is inching towards two per cent ofIndia's GDP. Hordes of new institutes are coming up in the nook and corner of the country—30 new central universities, 5 new Indian Institutes of Science Education and Research, 8 new Indian Institutes of Technology and 20 new Indian Institutes of Information Technology are in various stages of conception and completion.
However, simply increasing the number of institutes will not lead to better scientific prowess. The education system needs a complete rethink in order to attract more students to science and produce world class scientists (the last home-grown scientist to win a Nobel Prize was Sir C. V. Raman in 1930). In this direction, the INO is a giant leap forward because of its capacity to sustain research in subjects at the energy and cosmic frontiers, because of the special and exotic experimentation environments it will support, and because of the invaluable access it will provide to the Indian scientific community to cutting-edge information.
Star of the Orient
India’s first particle physics observatory is to be constructed in the district of Theni in Tamil Nadu at an expense of Rs. 1,200 crore (USD 250 million). Called the India-based Neutrino Observatory (INO), the entire experiment will be situated 1.3 km under a hill to keep other radiations and cosmic rays from interfering with the study. This is because the neutrinos that the detector will be studying rarely interact with matter and pass through it at the rate of three or four interactions per nearly 85 trillion trillion trillion. The gouging of a tunnel 7m wide and 1.9km long for accessing the cavern that will house the systems was commenced on October 14, Friday, and is expected to take a year.
Twenty-seven days ago, a startling discovery set off tremors across the scientific community when the Gran Sasso National Laboratory inItalyreported that certain fundamental particles called neutrinos had been observed moving faster than light. The reason this observation caused such dissonance and a flurry of excitement is that, according to the physics megagiant Albert Einstein, the Universe would allow nothing to travel faster than light.
Then again, conclusive proof was not presented by the physicists at the lab—at least, not anything that was within the infamous six-sigma accuracy tolerance limit: 99.99999 per cent. It was little surprise, then, that within a week of the report, engineers were working in full-swing atJapan's Kamioka reactor, at theUSA's dreaded Fermilab, at the Sudbury Neutrino Observatory inCanada, to recreate the conditions at Gran Sasso. Far away, in India, a country that had until then been the principle centre for processing second-hand information, a 22-year old plan was finally being mobilized.
With just a 29-year old history, the energy frontier of physics research was supposed to last at least until 2018—the year of the Super Large Hadron Collider. With such unprecedented discoveries, however, a shift away from high-energy research and toward ultra-rare processes has become conspicuous. For the INO, the timing couldn’t have been better.
The decision to locate the observatory at Theni was finalized after evaluating the local topography, seismic stability, environmental disturbance, rock quality, availability of electricity and water, and rain patterns. In order to further minimize the impact of the project’s logistical and infrastructural operations, an extant but little-used road is being re-laid for the trucks and earthmovers to use, instead of having them move through five villages.
Funded by the government of India and the Tata Institute of Fundamental Research (TIFR), and coordinated by the Institute of Mathematical Sciences (IMS), the INO will host a supersensitive static detector called the Iron Calorimeter (ICAL), incorporating a magnet exactly four times as large as the one in use at the Large Hadron Collider. Such an effort will involve the INO-industry interface in a big way, drawing heavily on available industrial infrastructure, in issues related to mechanical structure, electronics and detector-related technology.
The detector will consist of a stack of alternating plates of iron and borosilicate glass, each totally numbering 30,000 and measuring 12m to a side. The glass plates, in turn, will consist of glass sheets with a noble gas sandwiched in between—an arrangement referred to collectively as a resistive plate chamber (RPC). When a neutrino interacts with iron, it will knock out an electron from its orbit around an atom and send it into the RPC. Once there, the electron will be picked up by positively charged electrodes sewn into the glass, translated into a signal, and sent to the data processors.
The source of the neutrinos will be the sun, supernovae, cosmic rays and other intergalactic phenomena, and the output will correspond to the particle’s mass, position of interaction, velocity, type, degree of oscillation and charge.
There are two reasons the INO stands out from its peers: the first is that the ICAL is going to be devoted to studying neutrinos and neutrinos only, and the second is that the ICAL will study them continuously without stopping (except for scheduled maintenance). Because of such principled and technical dedication, physicists expect the detector to shine light on some of the more elusive characteristics of neutrinos, such as flavour oscillations and neutrino-neutrino interactions.
These are boom times for Indian science. The national spending on science and technology has gone up in the last five years and is inching towards two per cent ofIndia's GDP. Hordes of new institutes are coming up in the nook and corner of the country—30 new central universities, 5 new Indian Institutes of Science Education and Research, 8 new Indian Institutes of Technology and 20 new Indian Institutes of Information Technology are in various stages of conception and completion.
However, simply increasing the number of institutes will not lead to better scientific prowess. The education system needs a complete rethink in order to attract more students to science and produce world class scientists (the last home-grown scientist to win a Nobel Prize was Sir C. V. Raman in 1930). In this direction, the INO is a giant leap forward because of its capacity to sustain research in subjects at the energy and cosmic frontiers, because of the special and exotic experimentation environments it will support, and because of the invaluable access it will provide to the Indian scientific community to cutting-edge information.
Twenty-seven days ago, a startling discovery set off tremors across the scientific community when the Gran Sasso National Laboratory inItalyreported that certain fundamental particles called neutrinos had been observed moving faster than light. The reason this observation caused such dissonance and a flurry of excitement is that, according to the physics megagiant Albert Einstein, the Universe would allow nothing to travel faster than light.
Then again, conclusive proof was not presented by the physicists at the lab—at least, not anything that was within the infamous six-sigma accuracy tolerance limit: 99.99999 per cent. It was little surprise, then, that within a week of the report, engineers were working in full-swing atJapan's Kamioka reactor, at theUSA's dreaded Fermilab, at the Sudbury Neutrino Observatory inCanada, to recreate the conditions at Gran Sasso. Far away, in India, a country that had until then been the principle centre for processing second-hand information, a 22-year old plan was finally being mobilized.
With just a 29-year old history, the energy frontier of physics research was supposed to last at least until 2018—the year of the Super Large Hadron Collider. With such unprecedented discoveries, however, a shift away from high-energy research and toward ultra-rare processes has become conspicuous. For the INO, the timing couldn’t have been better.
The decision to locate the observatory at Theni was finalized after evaluating the local topography, seismic stability, environmental disturbance, rock quality, availability of electricity and water, and rain patterns. In order to further minimize the impact of the project’s logistical and infrastructural operations, an extant but little-used road is being re-laid for the trucks and earthmovers to use, instead of having them move through five villages.
Funded by the government of India and the Tata Institute of Fundamental Research (TIFR), and coordinated by the Institute of Mathematical Sciences (IMS), the INO will host a supersensitive static detector called the Iron Calorimeter (ICAL), incorporating a magnet exactly four times as large as the one in use at the Large Hadron Collider. Such an effort will involve the INO-industry interface in a big way, drawing heavily on available industrial infrastructure, in issues related to mechanical structure, electronics and detector-related technology.
The detector will consist of a stack of alternating plates of iron and borosilicate glass, each totally numbering 30,000 and measuring 12m to a side. The glass plates, in turn, will consist of glass sheets with a noble gas sandwiched in between—an arrangement referred to collectively as a resistive plate chamber (RPC). When a neutrino interacts with iron, it will knock out an electron from its orbit around an atom and send it into the RPC. Once there, the electron will be picked up by positively charged electrodes sewn into the glass, translated into a signal, and sent to the data processors.
The source of the neutrinos will be the sun, supernovae, cosmic rays and other intergalactic phenomena, and the output will correspond to the particle’s mass, position of interaction, velocity, type, degree of oscillation and charge.
There are two reasons the INO stands out from its peers: the first is that the ICAL is going to be devoted to studying neutrinos and neutrinos only, and the second is that the ICAL will study them continuously without stopping (except for scheduled maintenance). Because of such principled and technical dedication, physicists expect the detector to shine light on some of the more elusive characteristics of neutrinos, such as flavour oscillations and neutrino-neutrino interactions.
These are boom times for Indian science. The national spending on science and technology has gone up in the last five years and is inching towards two per cent ofIndia's GDP. Hordes of new institutes are coming up in the nook and corner of the country—30 new central universities, 5 new Indian Institutes of Science Education and Research, 8 new Indian Institutes of Technology and 20 new Indian Institutes of Information Technology are in various stages of conception and completion.
However, simply increasing the number of institutes will not lead to better scientific prowess. The education system needs a complete rethink in order to attract more students to science and produce world class scientists (the last home-grown scientist to win a Nobel Prize was Sir C. V. Raman in 1930). In this direction, the INO is a giant leap forward because of its capacity to sustain research in subjects at the energy and cosmic frontiers, because of the special and exotic experimentation environments it will support, and because of the invaluable access it will provide to the Indian scientific community to cutting-edge information.
Monday, 26 September 2011
My kingdom for a neutrino
In 1982, when the construction for CERN’s Large Hadron Collider (LHC) experiment was given the go-ahead, physics entered a very exciting period. It promised them the answers to their biggest questions and, in the event that that didn’t happen, it promised them ample evidence to come to a conclusion of their own.
Two decades later, with the device in full operation, results are emerging, some more improbable than the rest. The project was put in place to attempt to create the conditions of the Big Bang so physicists could detect the Higgs boson. However, nobody anticipated such a thing as evidence of super-luminary travel by neutrinos.
The existence of neutrinos was first proposed by Austrian physicist Wolfgang Pauli in 1930 to account for the excess mass and energy left behind after a neutron disintegrated into a proton and an electron. The first direct observation was to be made only in the 1970s, more than 40 years later. The neutrino is one of the many indivisible particles of this Universe, and is of neutral charge and very little mass. In fact, amongst all the particles that have any mass, a neutrino is the lightest. This means that according to Albert Einstein’s theory of relativity, the mass of the particle will hit infinity only when it travels at speeds terribly close to that of light. And by terribly close, I’m talking 99.9999% close.
Such neutrinos were generated by the LHC over the course of some of its experiments and sent to the Gran Sasso National Laboratory in Italy for study. Located 730 km south of the LHC and almost a kilometre under Mt. Gran Sasso, the laboratory receives the particles in a massive tank of ultra-pure water.
Once a neutrino comes in contact with a proton of a water molecule, they react to form a neutron and a positron. The positron collides with an electron, its anti-particle, to annihilate each other, releasing two gamma rays. The neutron is captured by another nucleus to release a third gamma ray. Therefore, the signature of a neutrino capture is the release of three gamma rays.
[caption id="attachment_20371" align="aligncenter" width="439" caption="The Super-KamiokaNDE experiment in Japan contains a tank of 50,000 litres of water, fit with an array of tens of thousands of photo-multiplier tubes (as above) to detect the release of energy in case of a neutrino capture. The cylindrical container has other systems in place to detect the position of a capture, too."]
[/caption]
At the laboratory, as scientists waited for the neutrinos to arrive and set off the reactions, they were hardly prepared when the release of the gamma rays was detected precisely 60 nanoseconds before it was due. While such a small difference might seem trivial, the implication is that the neutrinos arrived before any other kind of electromagnetic radiation did. Since electromagnetic radiations possess the fastest speed attainable in this Universe according to Einstein, the speeding neutrinos have possibly defied the greatest physicist of the last century.
Where does that leave the world of physics?
Centuries of hypothesizing and experimenting by scientists have ingrained the importance of reasoned scepticism in their minds. While the Gran Sasso National Laboratory has claimed that 16,000 such instances have been recorded and documented, they haven’t ruled out any errors. For now, physicists the world over await similar conclusions, and so confirmations, from the two other colliders capable of replicating such conditions.
One of them is the J-PARC in Japan. Located along the coast of the Tohoku prefecture, the device was damaged and unable to operate for the next 12 months, at least, by the earthquake in March 2011 in nearby Fukushima. The other collider is the Fermilab Tevatron, an atom-smasher of considerable reputation, in the USA. After close to three decades of operation, the facility is scheduled to shut down permanently on September 30, 2011.
Collaboration rather than competition seems to be the emerging mantra. The shadow of CERN is beginning to loom large on most particle physics labs, and they’re finding it difficult to compete with CERN and its flagship project. Further, in these days of ballooning fiscal deficits and bond rating downgrades in the US, funding is hard to come by for such "creamy" projects.
Unsurprisingly, physicists are prepared to wait. Why won’t they when the speed of light – a form of electromagnetic radiation – has been the definitive cornerstone of some of the most important foundations of our understanding of this Universe? By defying that limit, neutrinos have brought upon them the scrutiny of the entire scientific community.
For one, by being faster than light, neutrinos speeding toward Earth from distant stars get here before the image of the star does, making it possible for astrophysicists to peek farther back into history. Second, the particle that carries electromagnetic energy, the photon, was thought to be massless so it wouldn’t violate the theory of relativity. However, the neutrino has mass, and that means all of Einstein’s works will have to be disrobed and studied. The larger consequence of this is that almost all high-energy installations on this planet, ranging from nuclear power plants (NPPs) that power cities to radio-telescopes searching for extra-terrestrial life, become available for changes as much as at the design level.
(In an NPP, the flow of single-phase coolants in pressurized water reactors is assumed to flow not faster than the speed of light. Even if the fluid dynamics of single-phase coolants has already been modelled on luminary principles, how could there be any changes at the design level?
If the speed of the coolants can be increased even higher, then the critical discharge, i.e., the maximum flow rate permissible, will also go higher. This translates into enhanced cooling, and this obviously means that fuel rods can be made even thicker and more power could be generated.*)
Similarly, the way the world works also is not going to change since the neutrino has always been working the same way for billions of years irrespective of how we thought it worked. But what is going to change is the way we understand electromagnetic concepts. The Standard Model of particle physics, the Big Daddy of all the theories of physics, won’t have to be tweaked so much as twisted around to accommodate this yet-unsubstantiated phenomenon.
Physicists will wait, and while they wait, they’ll debate. They’ll conduct more experiments, record more data, hypothesize more, refute more, argue more, all the while hoping that the Tevatron will be fired up for one last battle, that the J-PARC will be resuscitated for a one-of-a-kind challenge. In my opinion, no overbearing modifications will have to be made to the pool of knowledge we possess regarding physics as such. Even if the neutrinos did travel at super-luminary speeds - which I highly doubt and attribute to minute measurement errors adding up to cause the spike - it won't be long before the concept of the phenomenon is quickly subsumed by the search for other even greater truths. Yes, our perspectives are going to change, but more than anything, the discovery's original role as a tool with which to discover more about nature will not.
Let's not get carried away, though. After all, disproving the greatest minds of physics in history requires a future of its own.
Two decades later, with the device in full operation, results are emerging, some more improbable than the rest. The project was put in place to attempt to create the conditions of the Big Bang so physicists could detect the Higgs boson. However, nobody anticipated such a thing as evidence of super-luminary travel by neutrinos.
The existence of neutrinos was first proposed by Austrian physicist Wolfgang Pauli in 1930 to account for the excess mass and energy left behind after a neutron disintegrated into a proton and an electron. The first direct observation was to be made only in the 1970s, more than 40 years later. The neutrino is one of the many indivisible particles of this Universe, and is of neutral charge and very little mass. In fact, amongst all the particles that have any mass, a neutrino is the lightest. This means that according to Albert Einstein’s theory of relativity, the mass of the particle will hit infinity only when it travels at speeds terribly close to that of light. And by terribly close, I’m talking 99.9999% close.
Such neutrinos were generated by the LHC over the course of some of its experiments and sent to the Gran Sasso National Laboratory in Italy for study. Located 730 km south of the LHC and almost a kilometre under Mt. Gran Sasso, the laboratory receives the particles in a massive tank of ultra-pure water.
Once a neutrino comes in contact with a proton of a water molecule, they react to form a neutron and a positron. The positron collides with an electron, its anti-particle, to annihilate each other, releasing two gamma rays. The neutron is captured by another nucleus to release a third gamma ray. Therefore, the signature of a neutrino capture is the release of three gamma rays.
[caption id="attachment_20371" align="aligncenter" width="439" caption="The Super-KamiokaNDE experiment in Japan contains a tank of 50,000 litres of water, fit with an array of tens of thousands of photo-multiplier tubes (as above) to detect the release of energy in case of a neutrino capture. The cylindrical container has other systems in place to detect the position of a capture, too."]
[/caption]At the laboratory, as scientists waited for the neutrinos to arrive and set off the reactions, they were hardly prepared when the release of the gamma rays was detected precisely 60 nanoseconds before it was due. While such a small difference might seem trivial, the implication is that the neutrinos arrived before any other kind of electromagnetic radiation did. Since electromagnetic radiations possess the fastest speed attainable in this Universe according to Einstein, the speeding neutrinos have possibly defied the greatest physicist of the last century.
Where does that leave the world of physics?
Centuries of hypothesizing and experimenting by scientists have ingrained the importance of reasoned scepticism in their minds. While the Gran Sasso National Laboratory has claimed that 16,000 such instances have been recorded and documented, they haven’t ruled out any errors. For now, physicists the world over await similar conclusions, and so confirmations, from the two other colliders capable of replicating such conditions.
One of them is the J-PARC in Japan. Located along the coast of the Tohoku prefecture, the device was damaged and unable to operate for the next 12 months, at least, by the earthquake in March 2011 in nearby Fukushima. The other collider is the Fermilab Tevatron, an atom-smasher of considerable reputation, in the USA. After close to three decades of operation, the facility is scheduled to shut down permanently on September 30, 2011.
Collaboration rather than competition seems to be the emerging mantra. The shadow of CERN is beginning to loom large on most particle physics labs, and they’re finding it difficult to compete with CERN and its flagship project. Further, in these days of ballooning fiscal deficits and bond rating downgrades in the US, funding is hard to come by for such "creamy" projects.
Unsurprisingly, physicists are prepared to wait. Why won’t they when the speed of light – a form of electromagnetic radiation – has been the definitive cornerstone of some of the most important foundations of our understanding of this Universe? By defying that limit, neutrinos have brought upon them the scrutiny of the entire scientific community.
For one, by being faster than light, neutrinos speeding toward Earth from distant stars get here before the image of the star does, making it possible for astrophysicists to peek farther back into history. Second, the particle that carries electromagnetic energy, the photon, was thought to be massless so it wouldn’t violate the theory of relativity. However, the neutrino has mass, and that means all of Einstein’s works will have to be disrobed and studied. The larger consequence of this is that almost all high-energy installations on this planet, ranging from nuclear power plants (NPPs) that power cities to radio-telescopes searching for extra-terrestrial life, become available for changes as much as at the design level.
(In an NPP, the flow of single-phase coolants in pressurized water reactors is assumed to flow not faster than the speed of light. Even if the fluid dynamics of single-phase coolants has already been modelled on luminary principles, how could there be any changes at the design level?
If the speed of the coolants can be increased even higher, then the critical discharge, i.e., the maximum flow rate permissible, will also go higher. This translates into enhanced cooling, and this obviously means that fuel rods can be made even thicker and more power could be generated.*)
Similarly, the way the world works also is not going to change since the neutrino has always been working the same way for billions of years irrespective of how we thought it worked. But what is going to change is the way we understand electromagnetic concepts. The Standard Model of particle physics, the Big Daddy of all the theories of physics, won’t have to be tweaked so much as twisted around to accommodate this yet-unsubstantiated phenomenon.
Physicists will wait, and while they wait, they’ll debate. They’ll conduct more experiments, record more data, hypothesize more, refute more, argue more, all the while hoping that the Tevatron will be fired up for one last battle, that the J-PARC will be resuscitated for a one-of-a-kind challenge. In my opinion, no overbearing modifications will have to be made to the pool of knowledge we possess regarding physics as such. Even if the neutrinos did travel at super-luminary speeds - which I highly doubt and attribute to minute measurement errors adding up to cause the spike - it won't be long before the concept of the phenomenon is quickly subsumed by the search for other even greater truths. Yes, our perspectives are going to change, but more than anything, the discovery's original role as a tool with which to discover more about nature will not.
Let's not get carried away, though. After all, disproving the greatest minds of physics in history requires a future of its own.
*On the other hand, for example, the speed at which the gravitational force acts on any body is limited to the speed of electromagnetic radiations, but that doesn't mean discovery of a higher speed in this Universe is going to change anything. It's only a role reversal at the most (although the massiveness of the neutrino is going to make a difference) because the practically achievable velocity is going to remain the same.
My kingdom for a neutrino
In 1982, when the construction for CERN’s Large Hadron Collider (LHC) experiment was given the go-ahead, physics entered a very exciting period. It promised them the answers to their biggest questions and, in the event that that didn’t happen, it promised them ample evidence to come to a conclusion of their own.
Two decades later, with the device in full operation, results are emerging, some more improbable than the rest. The project was put in place to attempt to create the conditions of the Big Bang so physicists could detect the Higgs boson. However, nobody anticipated such a thing as evidence of super-luminary travel by neutrinos.
The existence of neutrinos was first proposed by Austrian physicist Wolfgang Pauli in 1930 to account for the excess mass and energy left behind after a neutron disintegrated into a proton and an electron. The first direct observation was to be made only in the 1970s, more than 40 years later. The neutrino is one of the many indivisible particles of this Universe, and is of neutral charge and very little mass. In fact, amongst all the particles that have any mass, a neutrino is the lightest. This means that according to Albert Einstein’s theory of relativity, the mass of the particle will hit infinity only when it travels at speeds terribly close to that of light. And by terribly close, I’m talking 99.9999% close.
Such neutrinos were generated by the LHC over the course of some of its experiments and sent to the Gran Sasso National Laboratory in Italy for study. Located 730 km south of the LHC and almost a kilometre under Mt. Gran Sasso, the laboratory receives the particles in a massive tank of ultra-pure water.
Once a neutrino comes in contact with a proton of a water molecule, they react to form a neutron and a positron. The positron collides with an electron, its anti-particle, to annihilate each other, releasing two gamma rays. The neutron is captured by another nucleus to release a third gamma ray. Therefore, the signature of a neutrino capture is the release of three gamma rays.
[caption id="attachment_20371" align="aligncenter" width="439" caption="The Super-KamiokaNDE experiment in Japan contains a tank of 50,000 litres of water, fit with an array of tens of thousands of photo-multiplier tubes (as above) to detect the release of energy in case of a neutrino capture. The cylindrical container has other systems in place to detect the position of a capture, too."][/caption]
At the laboratory, as scientists waited for the neutrinos to arrive and set off the reactions, they were hardly prepared when the release of the gamma rays was detected precisely 60 nanoseconds before it was due. While such a small difference might seem trivial, the implication is that the neutrinos arrived before any other kind of electromagnetic radiation did. Since electromagnetic radiations possess the fastest speed attainable in this Universe according to Einstein, the speeding neutrinos have possibly defied the greatest physicist of the last century.
Where does that leave the world of physics?
Centuries of hypothesizing and experimenting by scientists have ingrained the importance of reasoned scepticism in their minds. While the Gran Sasso National Laboratory has claimed that 16,000 such instances have been recorded and documented, they haven’t ruled out any errors. For now, physicists the world over await similar conclusions, and so confirmations, from the two other colliders capable of replicating such conditions.
One of them is the J-PARC in Japan. Located along the coast of the Tohoku prefecture, the device was damaged and unable to operate for the next 12 months, at least, by the earthquake in March 2011 in nearby Fukushima. The other collider is the Fermilab Tevatron, an atom-smasher of considerable reputation, in the USA. After close to three decades of operation, the facility is scheduled to shut down permanently on September 30, 2011.
Collaboration rather than competition seems to be the emerging mantra. The shadow of CERN is beginning to loom large on most particle physics labs, and they’re finding it difficult to compete with CERN and its flagship project. Further, in these days of ballooning fiscal deficits and bond rating downgrades in the US, funding is hard to come by for such "creamy" projects.
Unsurprisingly, physicists are prepared to wait. Why won’t they when the speed of light – a form of electromagnetic radiation – has been the definitive cornerstone of some of the most important foundations of our understanding of this Universe? By defying that limit, neutrinos have brought upon them the scrutiny of the entire scientific community.
For one, by being faster than light, neutrinos speeding toward Earth from distant stars get here before the image of the star does, making it possible for astrophysicists to peek farther back into history. Second, the particle that carries electromagnetic energy, the photon, was thought to be massless so it wouldn’t violate the theory of relativity. However, the neutrino has mass, and that means all of Einstein’s works will have to be disrobed and studied. The larger consequence of this is that almost all high-energy installations on this planet, ranging from nuclear power plants (NPPs) that power cities to radio-telescopes searching for extra-terrestrial life, become available for changes as much as at the design level.
(In an NPP, the flow of single-phase coolants in pressurized water reactors is assumed to flow not faster than the speed of light. Even if the fluid dynamics of single-phase coolants has already been modelled on luminary principles, how could there be any changes at the design level?
If the speed of the coolants can be increased even higher, then the critical discharge, i.e., the maximum flow rate permissible, will also go higher. This translates into enhanced cooling, and this obviously means that fuel rods can be made even thicker and more power could be generated.*)
Similarly, the way the world works also is not going to change since the neutrino has always been working the same way for billions of years irrespective of how we thought it worked. But what is going to change is the way we understand electromagnetic concepts. The Standard Model of particle physics, the Big Daddy of all the theories of physics, won’t have to be tweaked so much as twisted around to accommodate this yet-unsubstantiated phenomenon.
Physicists will wait, and while they wait, they’ll debate. They’ll conduct more experiments, record more data, hypothesize more, refute more, argue more, all the while hoping that the Tevatron will be fired up for one last battle, that the J-PARC will be resuscitated for a one-of-a-kind challenge. In my opinion, no overbearing modifications will have to be made to the pool of knowledge we possess regarding physics as such. Even if the neutrinos did travel at super-luminary speeds - which I highly doubt and attribute to minute measurement errors adding up to cause the spike - it won't be long before the concept of the phenomenon is quickly subsumed by the search for other even greater truths. Yes, our perspectives are going to change, but more than anything, the discovery's original role as a tool with which to discover more about nature will not.
Let's not get carried away, though. After all, disproving the greatest minds of physics in history requires a future of its own.
Two decades later, with the device in full operation, results are emerging, some more improbable than the rest. The project was put in place to attempt to create the conditions of the Big Bang so physicists could detect the Higgs boson. However, nobody anticipated such a thing as evidence of super-luminary travel by neutrinos.
The existence of neutrinos was first proposed by Austrian physicist Wolfgang Pauli in 1930 to account for the excess mass and energy left behind after a neutron disintegrated into a proton and an electron. The first direct observation was to be made only in the 1970s, more than 40 years later. The neutrino is one of the many indivisible particles of this Universe, and is of neutral charge and very little mass. In fact, amongst all the particles that have any mass, a neutrino is the lightest. This means that according to Albert Einstein’s theory of relativity, the mass of the particle will hit infinity only when it travels at speeds terribly close to that of light. And by terribly close, I’m talking 99.9999% close.
Such neutrinos were generated by the LHC over the course of some of its experiments and sent to the Gran Sasso National Laboratory in Italy for study. Located 730 km south of the LHC and almost a kilometre under Mt. Gran Sasso, the laboratory receives the particles in a massive tank of ultra-pure water.
Once a neutrino comes in contact with a proton of a water molecule, they react to form a neutron and a positron. The positron collides with an electron, its anti-particle, to annihilate each other, releasing two gamma rays. The neutron is captured by another nucleus to release a third gamma ray. Therefore, the signature of a neutrino capture is the release of three gamma rays.
[caption id="attachment_20371" align="aligncenter" width="439" caption="The Super-KamiokaNDE experiment in Japan contains a tank of 50,000 litres of water, fit with an array of tens of thousands of photo-multiplier tubes (as above) to detect the release of energy in case of a neutrino capture. The cylindrical container has other systems in place to detect the position of a capture, too."]
[/caption]At the laboratory, as scientists waited for the neutrinos to arrive and set off the reactions, they were hardly prepared when the release of the gamma rays was detected precisely 60 nanoseconds before it was due. While such a small difference might seem trivial, the implication is that the neutrinos arrived before any other kind of electromagnetic radiation did. Since electromagnetic radiations possess the fastest speed attainable in this Universe according to Einstein, the speeding neutrinos have possibly defied the greatest physicist of the last century.
Where does that leave the world of physics?
Centuries of hypothesizing and experimenting by scientists have ingrained the importance of reasoned scepticism in their minds. While the Gran Sasso National Laboratory has claimed that 16,000 such instances have been recorded and documented, they haven’t ruled out any errors. For now, physicists the world over await similar conclusions, and so confirmations, from the two other colliders capable of replicating such conditions.
One of them is the J-PARC in Japan. Located along the coast of the Tohoku prefecture, the device was damaged and unable to operate for the next 12 months, at least, by the earthquake in March 2011 in nearby Fukushima. The other collider is the Fermilab Tevatron, an atom-smasher of considerable reputation, in the USA. After close to three decades of operation, the facility is scheduled to shut down permanently on September 30, 2011.
Collaboration rather than competition seems to be the emerging mantra. The shadow of CERN is beginning to loom large on most particle physics labs, and they’re finding it difficult to compete with CERN and its flagship project. Further, in these days of ballooning fiscal deficits and bond rating downgrades in the US, funding is hard to come by for such "creamy" projects.
Unsurprisingly, physicists are prepared to wait. Why won’t they when the speed of light – a form of electromagnetic radiation – has been the definitive cornerstone of some of the most important foundations of our understanding of this Universe? By defying that limit, neutrinos have brought upon them the scrutiny of the entire scientific community.
For one, by being faster than light, neutrinos speeding toward Earth from distant stars get here before the image of the star does, making it possible for astrophysicists to peek farther back into history. Second, the particle that carries electromagnetic energy, the photon, was thought to be massless so it wouldn’t violate the theory of relativity. However, the neutrino has mass, and that means all of Einstein’s works will have to be disrobed and studied. The larger consequence of this is that almost all high-energy installations on this planet, ranging from nuclear power plants (NPPs) that power cities to radio-telescopes searching for extra-terrestrial life, become available for changes as much as at the design level.
(In an NPP, the flow of single-phase coolants in pressurized water reactors is assumed to flow not faster than the speed of light. Even if the fluid dynamics of single-phase coolants has already been modelled on luminary principles, how could there be any changes at the design level?
If the speed of the coolants can be increased even higher, then the critical discharge, i.e., the maximum flow rate permissible, will also go higher. This translates into enhanced cooling, and this obviously means that fuel rods can be made even thicker and more power could be generated.*)
Similarly, the way the world works also is not going to change since the neutrino has always been working the same way for billions of years irrespective of how we thought it worked. But what is going to change is the way we understand electromagnetic concepts. The Standard Model of particle physics, the Big Daddy of all the theories of physics, won’t have to be tweaked so much as twisted around to accommodate this yet-unsubstantiated phenomenon.
Physicists will wait, and while they wait, they’ll debate. They’ll conduct more experiments, record more data, hypothesize more, refute more, argue more, all the while hoping that the Tevatron will be fired up for one last battle, that the J-PARC will be resuscitated for a one-of-a-kind challenge. In my opinion, no overbearing modifications will have to be made to the pool of knowledge we possess regarding physics as such. Even if the neutrinos did travel at super-luminary speeds - which I highly doubt and attribute to minute measurement errors adding up to cause the spike - it won't be long before the concept of the phenomenon is quickly subsumed by the search for other even greater truths. Yes, our perspectives are going to change, but more than anything, the discovery's original role as a tool with which to discover more about nature will not.
Let's not get carried away, though. After all, disproving the greatest minds of physics in history requires a future of its own.
*On the other hand, for example, the speed at which the gravitational force acts on any body is limited to the speed of electromagnetic radiations, but that doesn't mean discovery of a higher speed in this Universe is going to change anything. It's only a role reversal at the most (although the massiveness of the neutrino is going to make a difference) because the practically achievable velocity is going to remain the same.
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