I was randomly rewatching The Big Bang Theory on Netflix today when I spotted this gem:
Okay, maybe less a gem and more a shiny stone, but still. The screenshot, taken from the third episode of the sixth season, shows Sheldon Cooper mansplaining to Penny the work of Peter Higgs, whose name is most famously associated with the scalar boson the Large Hadron Collider collaboration announced the discovery of to great fanfare in 2012.
My fascination pertains to Sheldon’s description of Higgs as an “accomplished self-promoter”. Higgs, in real life, is extremely reclusive and self-effacing and journalists have found him notoriously hard to catch for an interview, or even a quote. His fellow discoverers of the Higgs boson, including François Englert, the Belgian physicist with whom Higgs won the Nobel Prize for physics in 2013, have been much less media-shy. Higgs has even been known to suggest that a mechanism in particle physics involving the Higgs boson should really be called the ABEGHHK’tH mechanism, include the names of everyone who hit upon its theoretical idea in the 1960s (Philip Warren Anderson, Robert Brout, Englert, Gerald Guralnik, C.R. Hagen, Higgs, Tom Kibble and Gerardus ‘t Hooft) instead of just as the Higgs mechanism.
No doubt Sheldon thinks Higgs did right by choosing not to appear in interviews for the public or not writing articles in the press himself, considering such extreme self-effacement is also Sheldon’s modus of choice. At the same time, Higgs might have lucked out and be recognised for work he conducted 50 years prior probably because he’s white and from an affluent country, both of which attributes nearly guarantee fewer – if any – systemic barriers to international success. Self-promotion is an important part of the modern scientific endeavour, as it is with most modern endeavours, even if one is an accomplished scientist.
All this said, it is notable that Higgs was also a conscientious person. When he was awarded the Wolf Prize in 2004 – a prestigious award in the field of physics – he refused to receive it in person in Jerusalem because it was a state function and he has protested Israel’s war against Palestine. He was a member of the Campaign for Nuclear Disarmament until the group extended its opposition to nuclear power as well; then he resigned. He also stopped supporting Greenpeace after they become opposed to genetic modification. If it is for these actions that Sheldon deemed Higgs an “accomplished self-promoter”, then I stand corrected.
Featured image: A portrait of Peter Higgs by Lucinda Mackay hanging at the James Clerk Maxwell Foundation, Edinburgh. Caption and credit: FF-UK/Wikimedia Commons, CC BY-SA 4.0.
Featured image: From left to right: Tom Kibble, Gerald Guralnik, Richard Hagen, François Englert and Robert Brout. Credit: Wikimedia Commons.
Sir Tom Kibble passed away on June 2, I learnt this morning with a bit of sadness that I’d missed the news. It’s hard to write about someone in a way that prompts others either to find out more about that person or, if they knew him or his work, to recall their memories of him when I myself would like only to do the former now. So let me quickly spell out why I think you should pay attention: Kibble was one of the six theorists who, in 1964, came up with the ABEGHHK’tH mechanism to explain how gauge bosons acquired mass. The ‘K’ in those letters stands for ‘Kibble’. However, we only remember that mechanism with the second ‘H’, which stands for Higgs; the other letters fell off for reasons not entirely clear – although convenience might’ve played a role. And while everyone refers to the mechanism as the Higgs mechanism, Peter Higgs, the man himself, continues to call it the ABEGHHK’tH mechanism.
Anyway, Kibble was known for three achievements. The first was to co-formulate – alongside Gerald Guralnik and Richard Hagen – the ABEGHHK’tH mechanism. It was validated in early 2013, earning only Higgs and ‘E’, François Englert, the Nobel Prize for physics that year. The second came in 1967, to explain how the mechanism accords the W and Z bosons, the carriers of the weak nuclear force, with mass but not the photons. The solution was crucial to validate the electroweak theory, and whose three conceivers (Sheldon Glashow, Abdus Salam and Steven Weinberg) won the Nobel Prize for physics in 1979. The third was the postulation of the Kibble-Żurek mechanism, which explains the formation of topological defects in the early universe by applying the principles of quantum mechanics to cosmological objects. This work was done alongside the Polish-American physicist Wojciech Żurek.
I spoke to Kibble once, only for a few minutes, at a conference at the Institute of Mathematical Sciences, Chennai, in December 2013 (at the same conference where I met George Sterman as well). This was five months after Fabiola Gianotti had made the famous announcement at CERN that the LHC had found a particle that looked like the Higgs boson. I’d asked Kibble what he made of the announcement, and where we’d go from here. He said, as I’m sure he would’ve a thousand times before, that it was very exciting to be proven right after 50 years; that it’d definitively closed one of the biggest knowledge gaps in modern theoretical particle physics; and that there was still work to be done by studying the Higgs boson for more clues about the nature of the universe. He had to rush; a TV crew was standing next to me, nudging me for some time with him. I was glad to see it was Puthiya Thalaimurai, a Tamil-language news channel, because it meant the ‘K’ had endured.
Particle physics is an obscure subject for most people but everyone sat up and took notice when the Large Hadron Collider discovered the particle named after Peter Higgs in 2012. The Higgs boson propelled his name to the front pages of newspapers that until then hadn’t bothered about the differences between bosons and fermions. On the other hand, it also validated a hypothesis he and his peers had made 50 years ago and helped the LHC’s collaborations revitalise their outreach campaigns.
However, much before the times of giant particle colliders – in the late 1950s, in fact – a cascade of theories was being developed by physicists the world over with much less fanfare, and a lot more of the quiet dignity that advanced theoretical physics is comfortable revelling in. It was a silent revolution, and led in part by the mild-mannered Yoichiro Nambu, who passed away on July 5, 2015.
His work and its derivatives gave rise to the large colliders like the LHC at work today, and which might well have laid the foundations of modern particle physics research. Moreover, many of his and his peers’ accomplishments are not easily discussed the way political movements are nor do they aspire to such privileges, but that didn’t make them any less important than the work of Higgs and others.
Yoichiro Nambu also belonged to a generation that marked a resurgence in Japanese physics research – consider his peers: Yoshio Nishina, Masatoshi Koshiba, Hideki Yukawa, Sin-Itiro Tomonaga, Leo Esaki, Makoto Kobayashi and Toshihide Maskawa, to name a few. A part of the reason was a shift in Japan’s dominant political attitudes after the Second World War. Anyway, the first of Nambu’s biggest contributions to particle physics came in 1960, and it was a triumph of intuition.
There was a span of 46 years between the discovery of superconductivity (by Heike Kamerlingh Onnes in 1911) and the birth of a consistent theoretical explanation for it (by John Bardeen, Leon Cooper and John Schrieffer in 1957) because the phenomenon seemed to defy some of the first principles of the physics used to understand charged particles. Nambu was inspired by the BCS theory to attempt a solution for the hierarchy problem – which asks why gravity, among the four fundamental forces, is 1032 times weaker than the strongest strong-nuclear force.
With the help of British physicist Jeffrey Goldstone, Nambu theorised that whenever a natural symmetry breaks, massless particles called Nambu-Goldstone bosons are born under certain conditions. The early universe, around 13.75 billion years ago when it was extremely small, consisted of a uniform pond of unperturbed energy. Then, the pond was almost instantaneously heated to a temperature of 173 billion Suns, when it broke into smaller packets called particles. The symmetry was (thought to be) spontaneously broken and the event was called the Big Bang.
Then, as the universe started to cool, these packets couldn’t reunify into becoming the pond they once made up, evolving instead into distinct particles. There were perturbations among the particles and the resultant forces were mediated by what came to be called Nambu-Goldstone bosons, named for the physicists who first predicted their existence.
Yoichiro in Nambu in 2008. Source: University of Chicago
Nambu was able to use the hypothetical interactions between the Nambu-Goldstone bosons and particles to explain how the electromagnetic force and the weak nuclear force (responsible for radioactivity) could be unified into one electroweak force at higher temperatures, as well as how where the masses of protons and neutrons come from. These were (and are) groundbreaking ideas that helped scientists make sense of the intricate gears that turned then to make the universe what it is today.
Then, in 1964, six physicists (Higgs, Francois Englert, Tom Kibble, Gerald Guralnik, C.R. Hagen, Robert Brout) postulated that these bosons interacted with an omnipresent field of energy – called the Higgs field – to give rise to the strong-nuclear, weak-nuclear (a.k.a. weak) and electromagnetic forces, and the Higgs boson. And when this boson was discovered in 2012, it validated the Six’s work from 1964.
However, Nambu’s ideas – as well as those of the Six – also served to highlight how the gravitational force couldn’t be unified with the other three fundamental forces. In the 1960s, Nambu’s first attempts at laying out a framework of mathematical equations to unify gravity and the other forces gave rise to the beginnings of string theory. But in the overall history of investigations into particle physics, Nambu’s work – rather, his intellect – was a keystone. Without it, the day theorists’ latinate squiggles on paper could’ve become prize-fetching particles in colliders would’ve been farther off, the day we made sense of reality farther off, the day we better understood our place in the universe farther off.
The Osaka City University, where Nambu was a professor, announced his death on July 17, due to an acute myocardial infarction. He is survived by his wife Chieko Hida and son John. Though he was an associate professor at Osaka from 1950 to 1956, he visited the Institute for Advanced Study at Princeton in 1952 to work with Robert Oppenheimer (and meet Albert Einstein). Also, in 1954, he became a research associate at the University of Chicago and finally a professor there in 1958. He received his American citizenship in 1970.
Peter Freund, his colleague in Chicago, described Nambu as a person of incredible serenity in his 2007 book A Passion for Discovery. Through the work and actions of the biggest physicists of the mid-19th century, the book fleshes out the culture of physics research and how it was shaped by communism and fascism. Freund himself emigrated from Romania to the US in the 1960s to escape the dictatorial madness of Ceausescu, a narrative arc that is partially reflected in Nambu’s life. After receiving his bachelor’s degree from the University of Tokyo in 1942, Nambu was drafted into the army and witnessed the infamous firebombing of Tokyo and was in Japan when Hiroshima and Nagasaki were bombed.
The destructive violence of the war that Nambu studied through is mirrored in the creative energies of the high-energy universe whose mysteries Nambu and his peers worked to decrypt. It may have been a heck of a life to live through but the man himself had only a “fatalistic calm”, as Freund wrote, to show for it. Was he humbled by his own discoveries? Perhaps, but what we do know is that he wanted to continue doing what he did until the day he died.
The world’s single largest science experiment will restart on March 23 after a two-year break. Scientists and administrators at the European Organization for Nuclear Research – known by its French acronym CERN – have announced the status of the agency’s upgrades on its Large Hadron Collider (LHC) and its readiness for a new phase of experiments running from now until 2018.
Before the experiment was shut down in late 2013, the LHC became famous for helping discover the elusive Higgs boson, a fundamental (that is, indivisible) particle that gives other fundamental particles their mass through a complicated mechanism. The find earned two of the physicists who thought up the mechanism in 1964, Peter Higgs and Francois Englert, a Nobel Prize in that year.
Though the LHC had fulfilled one of its more significant goals by finding the Higgs boson, its purpose is far from complete. In its new avatar, the machine boasts of the energy and technical agility necessary to answer questions that current theories of physics are struggling to make sense of.
As Alice Bean, a particle physicist who has worked with the LHC, said, “A whole new energy region will be waiting for us to discover something.”
The finding of the Higgs boson laid to rest speculations of whether such a particle existed and what its properties could be, and validated the currently reigning set of theories that describe how various fundamental particles interact. This is called the Standard Model, and it has been successful in predicting the dynamics of those interactions.
From the what to the why
But having assimilated all this knowledge, what physicists don’t know, but desperately want to, is why those particles’ properties have the values they do. They have realized the implications are numerous and profound: ranging from the possible existence of more fundamental particles we are yet to encounter to the nature of the substance known as dark matter, which makes up a great proportion of matter in the universe while we know next to nothing about it. These mysteries were first conceived to plug gaps in the Standard Model but they have only been widening since.
With an experiment now able to better test theories, physicists have started investigating these gaps. For the LHC, the implication is that in its second edition it will not be looking for something as much as helping scientists decide where to look to start with.
As Tara Shears, a particle physicist at the University of Liverpool, toldNature, “In the first run we had a very strong theoretical steer to look for the Higgs boson. This time we don’t have any signposts that are quite so clear.”
Higher energy, luminosity
The upgrades to the LHC that would unlock new experimental possibilities were evident in early 2012.
The machine works by using powerful electric currents and magnetic fields to accelerate two trains, or beams, of protons in opposite directions, within a ring 27 km long, to almost the speed of light and then colliding them head-on. The result is a particulate fireworks of such high energy that the most rare, short-lived particles are brought into existence before they promptly devolve into lighter, more common particles. Particle detectors straddling the LHC at four points on the ring record these collisions and their effects for study.
So, to boost its performance, upgrades to the LHC were of two kinds: increasing the collision energy inside the ring and increasing the detectors’ abilities to track more numerous and more powerful collisions.
The collision energy has been nearly doubled in its second life, from 7-8 TeV to 13-14 TeV. The frequency of collisions has also been doubled from one set every 50 nanoseconds (billionth of a second) to one every 25 nanoseconds. Steve Myers, CERN’s director for accelerators and technology, had said in December 2012, “More intense beams mean more collisions and a better chance of observing rare phenomena.”
The detectors have received new sensors, neutron shields to protect from radiation damage, cooling systems and superconducting cables. An improved fail-safe system has also been installed to forestall accidents like the one in 2008, when failing to cool a magnet led to a shut-down for eight months.
In all, the upgrades cost approximately $149 million, and will increase CERN’s electricity bill by 20% to $65 million. A “massive debugging exercise” was conducted last week to ensure all of it clicked together.
Going ahead, these new specifications will be leveraged to tackle some of the more outstanding issues in fundamental physics.
CERN listed a few–presumably primary–focus areas. They include investigating if the Higgs boson could betray the existence of undiscovered particles, the particles dark matter could be made of, why the universe today has much more matter than antimatter, and if gravity is so much weaker than other forces because it is leaking into other dimensions.
Stride forward in three frontiers
Physicists are also hopeful for the prospects of discovering a class of particles called supersymmetric partners. The theory that predicts their existence is called supersymmetry. It builds on some of the conclusions of the Standard Model, and offers predictions that plug its holes as well with such mathematical elegance that it has many of the world’s leading physicists enamored. These predictions involve the existence of new particles called partners.
In a neat infographic by Elizabeth Gibney in Nature, she explains that the partner that will be easiest to detect will be the ‘stop squark’ as it is the lightest and can show itself in lower energy collisions.
In all, the LHC’s new avatar marks a big stride forward not just in the energy frontier but also in the intensity and cosmic frontiers. With its ability to produce and track more collisions per second as well as chart the least explored territories of the ancient cosmos, it’d be foolish to think this gigantic machine’s domain is confined to particle physics and couldn’t extend to fuel cells, medical diagnostics or achieving systems-reliability in IT.
Here’s a fitting video released by CERN to mark this momentous occasion in the history of high-energy physics.
Featured image: A view of the LHC. Credit: CERN
Update: After engineers spotted a short-circuit glitch in a cooled part of the LHC on March 21, its restart was postponed from March 23 by a few weeks. However, CERN has assured that its a fully understood problem and that it won’t detract from the experiment’s goals for the year.
Of the six scientists who came up with the idea of a Higgs boson in the mid-1960s, independently or in collaboration with others, I’ve met all of one. Tom Kibble was at the Institute of Mathematical Science, Chennai, in January 2013 for a conference. He was 80 years old then, and looked quite frail. Every time somebody tapped his shoulder before taking a photograph, he would break into a self-effacing smile. It was clear he was surprised by the attention he was receiving. Kibble thought he didn’t deserve it.
He, Carl Hagen and Gerald Guralnik comprised one of the three teams that conceived the mechanism to explain how some fundamental particles acquired mass in the early universe, over time making possible chemical reactions, stars, life, and many things besides. The other two teams comprised Francois Englert and Robert Brout, and Peter Higgs; Higgs’ name has today become attached to the name of the mechanism. For their work, Higgs and Englert were awarded the 2013 Nobel Prize in physics. Brout couldn’t receive the prize because he had died in 2011. Kibble, Hagen and Guralnik were left out because of limits on how many people the prize could be awarded to at a time.
Fair share of obstacles
On April 26, 2014, Gerald Guralnik died of a heart attack in Rhode Island after delivering a lecture at Brown University. He was 77. In those seven decades, he had become one of the world’s leading experts on theoretical particle physics, which, through the 1960s, was entering its boom time as the world would later discover. In this period, he co-scripted one of the most enduring quests in modern physics research.
Before I started writing this, I visited the Wikipedia page for the Physical Review Letters papers published by the three groups that first called the world’s attention to their findings. In the second line, Peter Higgs is mentioned as having worked with Satyen Bose – undoubtedly the consequence of a grave misapprehension that pervaded India when the 2013 Nobel Prizes were announced. Many believed Satyen Bose had been neglected for his work, but he just hadn’t worked on the Higgs boson, only on the underlying theory that controls the lives and times of all bosons. If such are the facile issues that concern some misguided Indians today, Guralnik tackled more than a fair share in his time.
For a few years after Kibble, Hagen and Guralnik published their paper, their work wasn’t taken seriously. Guralnik wrote in Huffington Post in August 2012 that, in the summer of 1965, Werner Heisenberg – the originator of the notorious uncertainty principle – thought Guralnik’s ideas were junk. The New York Timeswrote that Robert Marshak, a famous theoretical physicist, told Guralnik that if he wished to survive in physics, he “must stop thinking about this sort of problem and move on,” advice that Guralnik “wisely obeyed”. According to Kibble, however, Marshak later admitted that he had been misguided.
Deference over primacy
Nevertheless, some other scientists had starting working on Guralnik & co.’s theories. By the 1970s, Sheldon Glashow, Abdus Salam and Steven Weinberg had succeeded in ironing out many of its inconsistencies and won the Nobel Prize for physics in 1979 for their work… even though it would be 50 more years to prove via experiment that the Higgs mechanism was for real. This is because there was no disputing that the implications of the work of Kibble, Hagen, Guralnik, Higgs, Brout and Englert were revolutionary, at least among those who were willing to accept it.
To this end, the 1979 prizewinners and the ‘Higgs Six’ were aware of and deferential toward the contributions of others to the development of this new theory. In fact, Higgs, who has often wound up being the centre of attention when talk of his eponymous mechanism comes up, has said that he’d rather call it the ABEGHHK’tH mechanism (A denoted Phillip Warren Anderson; ‘tH, Gerardus ‘t Hooft).
But others were less considerate, which didn’t go down well with Guralnik. As Kibble wrote in his obituary in Nature, “Guralnik came to feel that our early paper was often unfairly neglected. He gave talks and wrote papers pointing out our distinctive contribution, of which he was justifiably proud, and in which he was unquestionably the prime mover.” This doesn’t mean he went on to become a sour, old bat, of course, but only that Guralnik seemed to appreciate the gravitas of his work much more than others at the time. When Higgs and Englert shared the 2013 Nobel Prize in physics, Guralnik toldBrown Daily Herald that he was “a little hurt”, but happier for the recognition that his peers – and by extension his work – had received.
(It is, in fact, hard to say if he is as celebrated as Higgs is today, physicists notwithstanding. Such are the consequences of asymmetric recognition, a sort of ceiling effect that silences avant garde advancements until the world is ready to hear them. This is also a complaint I’ve heard from far too many Indian scientists and whose efforts to remedy it I don’t begrudge them even if it only seems like an infantile squabble over primacy.)
In fact, after his work in establishing the theoretical foundations of the Higgs mechanism, which itself is a cornerstone of a unified theory that describes both the electromagnetic and weak nuclear forces of nature, Guralnik proceeded to make a lot of other contributions. He worked on computational approaches to quantum field theory, quantum chromodynamics (i.e., the theory of the strong nuclear force), the application of chaos theory to particle physics, and string theory. His was a versatile genius, in part combative and in part pliant. Rest in peace.
Last week, as the Nobel Prizes were announced and Peter Higgs and Francois Englert won the highly coveted physics prize, dust was kicked up in India – just as it was in July and then in September 2012 – about how Satyendra Nath Bose had been ‘ignored’. S.N. Bose, in the 1920s, was responsible for formulating the Bose-Einstein statistics with Albert Einstein. These statistics described the physical laws that governed the class of particles that have come to be known, in honour of Bose’s work, as bosons.
The matter of ignoring S.N. Bose, on the other hand, was profoundly baseless, but a sensation realised only by a few in the country. Just because Bose had worked with bosons, many Indians, among them many academicians, felt he ought to have been remembered for his contribution. Only, they conveniently chose to forget, his contribution to the Nobel Prize for physics 2013 was tenuous and, at best, of historical value. I blogged about this for The Copernican science blog on The Hindu, and then wrote an OpEd along the same lines.
From the response I received, however, it seems as if the message is still lost on those who continue to believe Bose is now the poster-scientist for all Indian scientists whose contributions have been ignored by award-committees worldwide. Do we so strongly feel that post-colonial sting of entitlement?
July, 2012 – A Higgs boson-like entity is spotted at the Large Hadron Collider. Indians decry the lack of celebration of S.N. Bose, the Bengali physicist whom bosons are named for.
January, 2013 – The particle found at the LHC is confirmed to be a Higgs boson. Further outcry about S.N. Bose having been forgotten in favor of the “Western” intellects.
October, 2013 – Peter Higgs and Francois Englert win the 2013 Nobel Prize in physics for their work on the Higgs mechanism. Bose is also in the limelight but for the same wrong reasons.
The word ‘boson’ was named for S.N. Bose not because he discovered bosons. It was named so by Paul Dirac, a Nobel Prize winning physicist, to honour Bose’s contribution to the Bose-Einstein statistics, work he did with Albert Einstein on defining the general properties of all bosons.
There are two kinds of particles in nature. Matter particles are the proverbial building blocks. They are the quarks and leptons, together called fermions. Force particles guide the matter particles around and help them interact with each others. They are the photons, W and Z bosons, gluons and the Higgs bosons.
In 1924, Bose and Einstein developed a theory to explain how a group of identical but non-interacting particles may occupy different energy states. They drew up a set of statistical rules and the particles that followed these rules did not obey Pauli’s exclusion principle. All such particles came to be called bosons.
Similarly, in 1926, Enrico Fermi and Paul Dirac came up with a set of rules for particles that did obey Pauli’s exclusion principle. While they worked on this theory independently, Fermi’s results were published first, leading to Dirac calling these particles fermions in the Italian giant’s honour.
So there. S.N. Bose – good man, great contribution – but he has nothing to do with the Higgs boson in particular except that this particle is a boson. What’s being celebrated about the Higgs is not being done in denial of Bose’s contributions because there is nothing to deny. The physics behind what’s going on now has more to do with how the hunt for one particular boson is shaping modern particle physics. Face it, the world of science has moved on.
If anything, I liked this Outlook article (except the last line) published a day after the momentous CERN announcements on July 4 last year. It brought S.N. Bose back into the limelight at a time when few of us in the country had (or have) the scientific temperament to acknowledge such contributions from history and, simply, recognise and preserve it for what it is: homage.
Indeed, some Indians seem to harbour a maleficient sense of entitlement that extends to calls demanding the ‘B’ in ‘bosons’ be capitalised. Rolf Dieter-Heuer, Director General of CERN, responded to this while at a meeting in Kolkata in September 2012: “I was asked yesterday why the boson was not capped. In Bose’s own city today, we have capped the Boson. I, in fact, always cap the Boson. But today, we changed all our CERN slides to cap Bosons.”
Another example of misguided entitlement was some Indian physicists saying that ‘naming the Higgs particle after Bose is an honour bigger than the Nobel Prize itself’. If you’re looking for honour of Indian origin in the Nobel Prize for physics in 2013, look to Indian scientists who worked on the collider.
Look to contributions from the Tata Institute of Fundamental Research and the Institute of Mathematical Sciences. Look to the superconducting magnets technology that India provided. Look to people like Rohini Godbole, Kajari Mazumdar (see slide 4), and Ashoke Sen.
But if all you want to do is cling to the vestiges of a legacy you helped fade, then you’re also doomed, benumbed to the sting of being denied the Nobel Prizes only because you’re not producing and retaining Nobel-class thinkers anymore.
(This blog post first appeared at The Copernican on October 10, 2013.)
