Sir Tom Kibble, physicist – obituary Sir Tom Kibble, physicist – obituary Sir Tom Kibble Credit: Thomas Angus, Imperial College London 8 June 2016 • 5:23pm Sir Tom Kibble, who has died aged 83, was a leading British particle physicist whose work helped lead to the discovery of the Higgs boson, a sub-atomic particle named after Peter Higgs, the Edinburgh University physicist who in 1964 proposed its existence; when Higgs was awarded the Nobel Prize in Physics (with Francois Englert) in 2013, he said that Kibble should have been the third person on the podium. The search for the elusive particle began in the 1960s when three groups of scientists, working separately, were trying to build up quantum field theory, a mathematical description of the ways in which electromagnetic and nuclear forces interact at sub-atomic levels, in particular to solve the mystery of why some particles and objects are heavier than others – and why some have no mass at all.

Without some mechanism to account for this phenomenon, particles would never have coalesced into the complex structures that we see today, and everything from gorillas to galaxies would not exist. The Higgs boson, or “God Particle” as it also became known, explains how mass was imparted to elementary particles just after the Big Bang, and its discovery would put the final pieces into place for what is known as the Standard Model of particle physics. There were six people involved in publishing scientific papers in this field – Peter Higgs (working alone), the Belgian theoretical physicists François Englert and Robert Brout, working in collaboration, and Kibble, a physicist at Imperial College, London, working with the Americans Gerald Gulanik and Carl Hagen. Englert and Brout published first, in 1964, devising the equations of a mass-giving field that would pervade the cosmos and be consistent with relativity. Shortly afterwards Higgs made the same proposal, and pointed out that ripples in this field would take the form of a new particle. Later that same year, Kibble and his collaborators came to the same conclusion in a paper considered to be the most thorough and complete of the three.

Under the rules of the Nobel Prize no more than three living scientists can be given the award. Higgs and Englert were selected because they were the first two to publish (Brout’s death in 2011 meant he was ineligible). Higgs, however, pointed out that Kibble had gone on to perform further valuable independent work, notably publishing a key paper in 1967 in which he showed how the Higgs mechanism can be extended to explain how elementary particles known as the W and Z bosons have mass, whereas photons, which make up light, have none – in other words how the mass-giving mechanism works in the real world. Sir Tom Kibble Credit: Mike Finn-Casey, Imperial College London But the modest Kibble was always dubious about the idea of awards for his work. His son Robert recalled in an interview that his father had seemed excited about only one award he had received – the Nesta award for creative mentoring in science, which he won in 2005.

“Our paper was unquestionably the last of the three,” Kibble said, after hearing about the Nobel, “and it is therefore no surprise that the Swedish Academy felt unable to include us, constrained as they are by a self-imposed rule that the prize cannot be shared by more than three people.” Thomas Walter Bannerman Kibble was born on December 23 1932 in Madras, where his father, Professor Walter Kibble, taught Mathematics and Statistics at the Madras Christian College in Tambaram. His maternal grandparents were Helen Bannerman, best known as the author of Little Black Sambo, and William Bannerman, an officer in the Indian Medical Service. Tom Kibble was educated at Doveton Corrie School in Madras, India, then at Melville College, Edinburgh and Edinburgh University, where he read Mathematics and Mathematical Physics. He arrived at Imperial College in 1959, joining the research group founded by Professor Abdus Salam. Over the course of his career Kibble made many other important contributions to theoretical physics, including how defects known as “cosmic strings” might have formed in the early universe.

Although these “strings” have not yet been observed by physicists, similar effects have been recreated in laboratories, where their formation is explained by an effect known as “Kibble-Zurek scaling”, named after Kibble and Wojciech Zurek. In 1970 Kibble became Professor of Theoretical Physics at Imperial, and held the position of head of the Department of Physics from 1983 to 1991. In 2008 the paper he wrote with his two colleagues in 1964 was selected as one of the most important papers of the last 50 years by the journal Physical Review Letters. In 2009 he was jointly awarded the 2010 JJ Sakurai Prize for Theoretical Particle Physics – one of the most important international prizes in physics. In 2013 he was appointed one of four new honorary fellows of the Institute of Physics, and received the Dirac Medal, which is given to scientists who have made significant contributions to theoretical physics.

Kibble, who listed “destructive gardening” among his recreations, was in Central Hall Westminster in July 2012, when scientists at Cern announced the Large Hadron Collider had discovered a particle commensurate with the long-awaited Higgs boson. “It felt quite surreal, actually,” he said later. Kibble was elected a Fellow of the Royal Society in 1980, served as its vice-president in 1988-89 and won its Royal Medal in 2012. He was appointed CBE in 1998 and knighted in 2014. In 1957 he married Anne Allan, who died in 2005. He is survived by their son and two daughters. Sir Tom Kibble, born December 23 1932, died June 2 2016 Follow the latest Telegraph Obituaries news READ MORE ABOUT: In search of the God particle | The Independent Science In search of the God particle Science is all about big ideas. But few come bigger than the 'Higgs bosOn' &ndash; a theory that may unlock the universe's deepest secrets.

Steve Connor reports on the experiment of the century Monday 7 April 2008 23:00 BST Click to follow In search of the God particle 1/3 3/3 EPA/SALVATORE DI NOLFI It is not everyday that someone's name becomes inextricably linked with God. But it is not everyday that someone comes up with a theory that could help to unify the many disparate forces of the universe. All the more strange, then, for the man behind the sub-atomic "God particle" to be an unassuming grandfather living in modest retirement in one of the more sedate districts of Edinburgh. Indeed, Professor Peter Higgs, 78, is modesty personified. A theoretical particle physicist, it took him 20 years before he could even bring himself to call the God particle by its more scientific name – the Higgs bosOn. Up to that point, he preferred the more prosaic term, "scalar boson". He still squirms when people refer to it by the deified moniker coined many years ago by a brasher colleague.

"I find it embarrassing because, although I'm not a believer myself, it's the sort of misuse of terminology that might offend some people," he said. And if Peter Higgs is anything, he's not someone to go around offending people. He first formulated the theory behind the sub-atomic particle named after him in the 1960s, and for almost half a century it has remained as elusive as stardust. That could all change later this year, however, when one of the world's biggest experiments is switched on deep beneath the Alpine meadows on the Franco-Swiss border, the home of the European Centre for Nuclear Research (Cern) near Geneva. Within a 27km-long, circular tunnel – as big as the Circle line on the London Underground – atom will be smashed into atom at something approaching the speed of light. The machine, called the Large Hadron Collider (LHC), is built to produce energy levels expected to be powerful enough to shake out the elusive Higgs bosOn from its seemingly inescapable prison within the atomic nucleus. The Higgs is just one of the discoveries that the LHC is expected to make.

The international team of physicists behind the project believes that the LHC will almost certainly produce a jewel box of discoveries that will light up the infinitesimally small world of sub-atomic physics. "The actual discovery of the Higgs bosOn, if it happens, is only one part of the programme. There is vastly more for the machine to do," Professor Higgs said. "I'm most excited for instance about the possible identification of super-symmetry particles – symmetrical particles of the particles we already know". Supersymmetry refers to the "grand dance" of particles in the universe. We know of about a dozen sub-atomic particles, which have exotic names such as quark, lepton and neutrino. Yet for every kind of particle, there may a super-symmetrical partner. The trouble is, we can only see one of the partners in each dancing couple, with the "significant others" remaining invisible. If supersymmetry is confirmed by the LHC it will help scientists towards the ultimate goal of a unified theory for the fundamental forces of nature – in particular the force of gravity which so far lies outside the realm of the forces known at the quantum level of the sub-atomic particle.

"The reason it's exciting is that I'm interested in a unified theory of forces, in particular quantum gravity," Professor Higgs said. Although long retired from research, he still possesses a child-like wonder of the world which we cannot see but which is so critical to some of the most important questions at the centre of our understanding of creation, the universe and the end of time. Professor Higgs was speaking to the press yesterday after spending much of the weekend seeing the LHC for the first time, before it is sealed in preparation for the switch-on in summer. It was the first time he had been to Cern since 1985, and the first time he had spent any appreciable time there since a short research project in 1976. "The sheer scale of the detectors is overwhelming. It's far more impressive than anything you get out of photographs," he said. The detectors in question are four huge underground instruments, some as big as a gothic cathedral, which will act as microscopes to identify a Higgs particle in a fraction of the split second it takes to make an appearance before it disappears once more.

Professor Higgs said he is 90 per cent certain the LHC will find his particle when it reaches its full working potential, perhaps in a year's time. If the machine does find the Higgs, it will cap an extraordinary career for the Bristol-born mathematician, given that he first proposed the idea more than 40 years ago when he was a young theoretical physicist at the University of Edinburgh. It will also solve one of the most pressing problems in science because the Higgs bosOn lies at the heart of matter itself. In particular it is supposed to explain why objects have mass and while some phenomena – such as light – do not. Professor Higgs was the first to propose the theory that the reason why objects have mass is because they interact with an invisible field, now called the Higgs field. Heavier particles interact more strongly, whereas photons (light particles) do not interact at all. Without this Higgs field, everything – from proton to planet – would be as insubstantial as a light beam. When Higgs first came up with the idea, few people took him seriously and even the then editor of a leading physics journal – who was based at Cern – thought it was too conjectural to be published.

"At the time I started this work, it was rather an unfashionable thing to be interested in, certainly on this side of the Atlantic ... my colleagues thought I was a bit of an idiot," Professor Higgs recalled. "A colleague told me that at Cern they didn't see what I was talking about had much to do with particle physics. So I added on a few extra paragraphs [to the original scientific paper] and sent it off across the Atlantic to [the journal] Physical Review Letters, which did accept it," he said. Four decades later, Cern is in pole position in the race to be first to find the Higgs although its advantage has been eroded. The LHC should have opened three years ago but, as with all big engineering and construction projects, it was dogged by delays. Meanwhile, another atom smasher at the Fermi Laboratory in the United States may have come close to solving the problem. Professor Higgs said the Fermi Lab scientists may have already done it, but may not yet be in a position to prove it because the critical evidence may still locked up in data obscured by background noise. Professor Higgs said that it's not something he's going to mention to the people at Cern. "It's a possibility.

I think the race is a very close thing. Fermi Lab are obviously trying very hard, they have a disadvantage compared to LHC when it starts, in terms of lack of luminosity, comparatively speaking – so it's for them to find it," he said. "But it could be there in their data, but not just found in the analysis, yet. They are certainly hoping that they'll get their first indication before the LHC gets going." But time is running out for the Fermi Lab, as the giant, supercooled magnets at the LHC are being prepared for their task of keeping the particle beams swirling round the tunnel with pin-point accuracy at the rate of more than 22,000 times a second. Just the amount of supercooling involved is stupendous – enough deep freeze to keep 140,000 kitchen fridges just above absolute zero, which is –273C. In fact, when it is fully operational, the LHC will be the coldest place in the known universe.

There are enough supercooled cables in the LHC to go around the equator 6.8 times, and enough filaments in the cable strands to stretch to the sun and back five times – and enough left over for a few return trips to the moon. The immense energies involved in making the atomic collisions happen have already generated unwelcome publicity for the LHC. Some scientists have suggested that they may generate mini black holes, which have led others to suggest that these black holes could somehow merge to form a larger, destructive entity that could swallow up the entire earth. "The black hole business has become rather inflated," said Professor Higgs, irritated by the suggestion that the LHC could become an unwitting doomsday machine. "Even the theorists who are suggesting that mini-black holes are things that could be produced are not predicting black holes large enough to swallow up chunks of the universe. I think the publicity has rather got out of hand and some people have misunderstood it," he said. Hysteria aside, Professor Higgs seemed pleased that so many people outside the rarefied world of particle physics and cosmology are taking an interest in what will happen at Cern in the coming few years.

He for one is certain that something awesome is about to happen, even if his particle is not found – although he thinks that is unlikely. "I'd be very puzzled if it wasn't discovered ... If you don't have something like a Higgs bosOn ... if it's not that, what the hell is it? If it's not found, I no longer understand what I think I understand," he said. And if it is found? "I shall open a bottle of something." More about: Higgs boson: First hard evidence of God particle found by CERN | Daily Mail Online comments One of CERN's most senior physicists this afternoon announced firm evidence for the existence of the elusive Higgs Boson, or God particle. Although the signal doesn't meet strict scientific standards for a 'full scientific discovery', it's still enough for researchers at CERN'S Large Hadron Collider (LHC) to predict a discovery next year. Two separate teams of scientists have been running independent experiments in secret from each other in order to improve the veracity of the results with the team leader of one, Fabiola Gianotti, proclaiming that they believe they've found signs of the Higgs boson in the past year.

A typical 'candidate event' for the Higgs boson, including two high-energy photons whose energy (depicted by red towers) is measured by CMS. The yellow lines are the measured tracks of other particles produced in the collision Size matters: The CMS detector weighs a staggering 13,000 tons Higgs hunters: A graphic showing a collision at full power at the CMS detector control room FROM THE BIG BANG TO THE 1960s The existence of the Higgs boson was put forward in the 1960s to explain why the tiny particles that make up atoms have mass. Theory has it that as the universe cooled after the Big Bang, an invisible force known as the Higgs field formed. This field permeates the cosmos and is made up of countless numbers of tiny particles – or Higgs bosons. As other particles pass through it, they pick up mass. Any benefits in the wider world from the discovery of the Higgs boson will be long term, but they could be felt in fields as diverse as medicine, computing and manufacturing. Experts compare the search for the Higgs boson to the discovery of the electron.

The idea of the electron – a subatomic particle – was first floated in 1838, but its presence was not confirmed for another 60 years. A century on, the electron’s existence underpins modern science. Our understanding of it is critical to the development of technology from television and CDs to radiotherapy for cancer patients. 'We have built a solid foundation for the months ahead,' she said. UK particle physicist Tara Shears was also upbeat, saying that the results represented 'exciting times' with 'more to come'. Professor Stefan Soldner-Rembold, a particle physicist from the University of Manchester, told MailOnline: 'ATLAS and CMS [the two detectors in the hunt for Higgs] have presented an important milestone in their search for the Higgs particle, but it is not yet sufficient for a proper discovery given the amount of data recorded so far.

'Still, I am very excited about it, since the quality of the LHC results is exceptional.' CERN was cautious: 'The main conclusion is that the Standard Model Higgs boson, if it exists, is most likely to have a mass constrained to the range 116-130 GeV [a unit of energy equal to billion electron volts] by the ATLAS experiment, and 115-127 GeV by CMS. 'Tantalising hints have been seen by both experiments in this mass region, but these are not yet strong enough to claim a discovery. 'Higgs bosons, if they exist, are very short lived and can decay in many different ways. Discovery relies on observing the particles they decay into rather than the Higgs itself. Both ATLAS and CMS have analysed several decay channels, and the experiments see small excesses in the low mass region that has not yet been excluded.' The upshot of the experiments, therefore, is that researchers believe the Higgs is fairly lightweight, which could lead to more exciting discoveries, according to New Scientist's Lisa Grossman.

She wrote: 'A Higgs of this mass, about 125 gigaelectronvolts, would blast a path to uncharted terrain. Such a lightweight would need at least one new type of particle to stabilise it.' When looking at results, the scale of certainty used by researchers is the sigma, something peculiar to particle physics. Researchers need a five-sigma level of certainty to make a bona-fide formal discovery, which means there’s only a one in a million chance that the result is a statistical error. Scientists only formally acknowledge an experiment’s results if they hit a three sigma level, which means there’s only a 1 in 370 chance of them being a fluke. RELATED ARTICLES Share this article Share The sigma probabilities announced today for the Higgs hunt have not been combined, but the overall ATLAS result was 2.3. Before the press conference began, CERN described the room as 'full to the rafters. People would hang from the lamps if the security guards would let them'. This graphic explains how protons are smashed in the Large Hadron Collider The Higgs boson is regarded – by those who know about such things – as the key to understanding the universe.

Its job is, apparently, to give the particles that make up atoms their mass. Without this mass, these particles would zip though the cosmos at the speed of light, unable to bind together to form the atoms that make up everything in the universe, from planets to people. The Higgs boson’s existence was predicted in 1964 by Edinburgh University physicist Peter Higgs. But it has eluded previous searchers – so much so that not all scientists believe in its existence. The hunt for the Higgs boson was one of the LHC's major tasks. The collider, housed in an 18-mile tunnel buried deep underground near the French-Swiss border, smashes beams of protons – sub-atomic particles – together at close to the speed of light, recreating the conditions that existed a fraction of a second after the Big Bang. If the physicists’ theory is correct, a few Higgs bosons should be created in every trillion collisions, before rapidly decaying. This decay would leave behind a ‘footprint’ that would show up as a bump in their graphs.

The CMS – or Compact Muon Solenoid – is a 13,000-ton machine that sits 330 feet underground, while the ATLAS, at 148 feet long and 82 feet high, is the biggest detector ever constructed. Cutting edge: A physicist explains the ATLAS experiment on a board at CERN World bows before Elswick's physicist; HIGGS BOSON PARTICLE. - Free Online Library World bows before Elswick's physicist; HIGGS BOSON PARTICLE. <a href=" Citations: APA style: World bows before Elswick's physicist; HIGGS BOSON PARTICLE.. (n.d.) >The Free Library. (2014). Retrieved Jan 05 2017 from Byline: Michael Brown WALKING in the mountains almost 50 years ago, Newcastle-born Peter Higgs may not have realised that one day his name would be on the lips of half the world. Even a few years ago, the quiet and unassuming physicist was a virtual unknown outside academic circles, with his greatest work better known by its more media-friendly moniker, the God particle.

But the former physics professor, who is now 84, wept yesterday at the globe's biggest laboratory when it was announced that his fellow scientists have seemingly proved him right, finding evidence of what they think is the "glue" that holds the universe together. "I'm rather surprised that it happened in my lifetime," said the son of a BBC sound engineer who grew up in Elswick, in Newcastle's West End. "I certainly had no idea it would happen in my lifetime at the beginning, more than 40 years ago, because at the beginning people had no idea about where to look for it, so it's really amazing for me. "I think it shows amazing dedication by the young people involved with these colossal collaborations to persist in this way, on what is a really a very difficult task. I congratulate them." In 1964, while walking through the Cairngorms in Scotland, Prof Higgs came up with the idea that particles - also known as bosons - derive their mass from the speed at which they pass through a field of much smaller particles, which were given the name Higgs bosons.

The idea became one of the main tenets on which quantum physicists built the Standard Model of how the universe works and scientists have spent nearly 50 years hunting down the elusive proof that the Higgs boson exists. Such efforts took a leap forward with the opening in 2008 at CERN - the European Laboratory for Particle Physics - of the Large Hadron Collider, a 17-mile long, high energy particle accelerator that was constructed under the mountains of Switzerland. Among those putting forward their expertise to help devise and analyse the experiments at the LHC were members of Durham University's Institute for Particle Physics Phenomenology. The group's director, Professor Valentin Khoze, said the mounting evidence that the particle had been produced and detected was "a triumph for particle physics." "Higgs boson play an absolutely vital role in our very understanding of fundamental physics," he said. "Without the Higgs particle, other particles such as electrons and quarks would be massless and the universe would not be what it is.

"Now, with the amazing results from the LHC, we are finally starting to find the experimental evidence that the Higgs really exists." But Prof Khoze said the work was far from over and, for scientists, the second stage of the story could be even more exciting than the first. "This discovery provides us with a window to new physics, a tool for the exploration of the truly unknown. "The next stage will be a detailed and careful study of its properties. Successful completion of this second stage will bring us closer to uncovering new physics, explaining dark matter and other mysteries of the universe." The first suggestion that scientists may have found a Higgs-like particle came last December but, ever cautious - particularly in the wake of last year's laterdisproved claim from CERN that neutrinos had been observed travelling faster than light - the academics sifted through billions of tests worth of data to try to confirm their initial results. Yesterday, they said two of the LHC's giant detectors, CMS and Atlas, had delivered results that reached the definitive "five sigma" level of proof, when the likelihood of a statistical fluke is one in a million.

Future research may uncover more than one Higgs boson, or find better ways of describing the universe than the Standard Model, which would have had to be torn up if the event the particle didn't exist. One theory, called "supersymmetry", claims more than five Higgs-like particles may be out there, each with completely different properties. Professor Jon Butterworth, from University College London, said regardless of the next step, right now he was just over the moon. "We don't know exactly what we've discovered but it's fundamental, new and exciting, and it looks like the Higgs boson," he said. "I think it's something so like the Standard Model Higgs that any differences will be incidental. We still need to see that it does the job the Higgs is there for, which is to give particles mass. I feel absolutely elated." Even Prime Minister David Cameron passed on his congratulations. "It is a very big step forward and we should congratulate everyone involved," he said. MOUNTAIN TREK LED TO MOMENT OF INSPIRATION UNTIL recently, Professor Peter Higgs was as unknown to most of the world as the famous particle that bears his name.

Today the quiet physicist, now retired from the University of Edinburgh, is fast becoming a global celebrity as creator of the theory behind the God particle. And the man born in Newcastle in 1929, the son of a BBC sound engineer, could now be eligible for a Nobel Prize. Prof Higgs, 83, has been waiting since 1964 for science to catch up with his ideas about the Higgs boson. It was in that year he dreamed up the concept in a moment of inspiration while walking in the Cairngorms. Two scientific papers followed, the second of which was initially rejected and then finally published in the respected journal Physical Review Letters. Prof Higgs's groundbreaking proposal was that particles acquire mass by interacting with an all-pervading field spread throughout the universe. The more they interact, the more massive and heavy they become. A "boson" particle was needed to carry and transmit the effect of the field - the Higgs boson. After his family moved to Bristol, he proved a brilliant pupil at Cotham Grammar School before going on to read theoretical physics at King's College London.

He was awarded first-class honours in 1950, and after failing to secure a lectureship at King's College, set off for Scotland. In 2006, he retired from the University of Edinburgh, assuming the title of emeritus professor. Never one to blow his own trumpet, Prof Higgs is described by friends and colleagues as very unassuming and shy. Some believe his retiring nature might even have held back his career. Now, despite his best efforts to keep a low profile, the spotlight will be fixed on him for some time. ATOMS, PROTONS AND PASTIES TO make matter you only need three things - electrons, an up quark and a down quark. Using the quarks you can make protons and neutrons, and when you put a few of those together with electrons you get an atom. However, scientists have so far discovered 12 sub-atomic particles and there could be many more. To try and make sense of what all these particles are for, scientists have organised them depending on how they behave, almost like the periodic table of elements. And to try to find if there are any other varieties they use a particle accelerator to smash protons together.

But when you smash particles together what you get out isn't necessarily what you put in, as the particles turn into a kind of energy - known as a force-carrying boson - and that can be used to make any other particle for which you have enough energy. Put simply, it's like two people walking into Greggs, one with enough money for a cheese and onion pasty and the other enough for a packet of jam doughnuts. The pair bump into each other and drop their wallets, with the money going everywhere. The wallets are the protons and the coins inside the bosons. Now with the combined coins the pair can buy anything up to the value of the cash, be that one chicken tandoori sandwich or a steak bake, sausage roll and a cupcake. The more money - energy - in the two wallets to begin with, the more possible outcomes - to the point where if there's enough money the duo might even get to go and buy something off the completely different menu in the McDonalds next door. What Peter Higgs predicted was given enough energy you would see the presence of a particle called the Higgs Boson, which gives other particles mass. What is mass?

To most people mass means the amount of "stuff" something has to it - but an electron has mass but no volume, so there's no "stuff" in it. So the best way to think of mass is probably just as a characteristic of a particle, like charge. And when two things have mass they will attract together. Where does the mass come from? Imagine a children's ball pool that covers the entire universe. Every particle feels the ball pool as it moves, but some can pass through it faster than others. Those that pass through it more quickly have a small mass, while those slowed down a lot have a large mass. Why has it taken so long to find this Higgs-like particle? Well if you smash two particles together and make a Higgs it may go on to form, say, two bottom quarks. But like the Greggs analogy there's many ways to afford a pepperoni slice, so buying the pizza isn't an indication of the coinage used. Why hasn't it been seen until now?

The intermediate stage of the process in which the particles become energy before turning back into particles might only appear for 0.00000000000000000000001 seconds and obviously you only get one chance to spot it. To reach this stage has required the Large Hadron Collider to smash protons together millions of times, every day, for years and then a small army of scientists to analyse the results and look for the tiny variance that proves the existence of a particle in a Higgs-like energy state. CAPTION(S): SURPRISED Peter Higgs' theory is proved AT LAST A scientist looks at the pictures of the first collisions at full power at the CMS Experience control room at CERN's European Laboratory for Particle Physics COPYRIGHT 2012 MGN Ltd. No portion of this article can be reproduced without the express written permission from the copyright holder. Copyright 2012 Gale, Cengage Learning. All rights reserved.

Article Details Higgs boson announcement: Cern scientists discover subatomic particle | Science | theguardian.com Higgs boson announcement: Cern scientists discover subatomic particle Scientists gather for a major announcement in Cern, home of the Large Hadron Collider What happens inside the Large Hadron Collider. Scientists at Cern, near Geneva, have this morning announced the likely discovery of the Higgs boson particle. Photograph: Cern 7.17am: Good morning all. Two teams of physicists at the Cern laboratory near Geneva are preparing today to announce their latest efforts to discover the Higgs boson . Participants take a rest early before the opening of the seminar. Photograph: Denis Balibouse/AFP/Getty Images The elusive "God particle" has become the most sought-after particle in modern science. Its discovery would be proof of an invisible energy field that fills the vacuum of space, and excitement in the scientific community is at fever pitch.

Peter Higgs, the Edinburgh University physicist who proposed the idea of the particle in 1964, is flying in to Geneva, as are two other men who published similar theories at around the same time: François Englert, professor emeritus at the Free University of Brussels (ULB) in Belgium, and Tom Kibble, professor emeritus at Imperial College London. There have been rumours, speculation, and, last night, even an apparent leak from the laboratory when a video announcing the discovery of a new particle was accidentally posted on its website. The Guardian's Ian Sample has flown to Geneva and I'll be live-blogging this potentially historic morning on this page. 7.38am: Now, two video links for your viewing pleasure. This one is to Cern's own live stream from where the scientific session is due to start at 9am local time (8am British time) - and subsequent press conference - will be held. And here is a video from the Guardian's own resident boffin, science correspondent Ian Sample. Heroically, he attempts to explain the Higgs boson by means of a tray from our canteen and some coloured ping pong balls.

British physicist Peter Higgs (right) arrives at the seminar. Photograph: Fabrice Coffrini/AFP/Getty Images 7.52am: Clapping for Peter Higgs, who has just arrived in the auditorium. Now, the anticipation mounts. 8.02am: And we're off. First up is Joe Incandela, the leader of the team using the CMS detector to search for new particles. He'll be followed by Fabiola Gianotti from the other team using the Atlas detector. He says the results are "very strong, very solid". 8.13am: As Incandela speaks, the brilliant Ian Sample is live-tweeting from Cern. I've been told that anyone who thinks they haven't found a new particle after this has lost touch with reality. #cern #lhc #higgs #ichep2012 — New Scientist (@newscientist) July 4, 2012 9.14am: "Both experiments observe a new particle in the mass region around 125-126 GeV," confirms a press release from Cern.

Gianotti- who is still speaking- is quoted in this release as saying: We observe in our data clear signs of a new particle, at the level of 5 sigma, in the mass region around 126 GeV. The outstanding performance of the LHC and ATLAS and the huge efforts of many people have brought us to this exciting stage, but a little more time is needed to prepare these results for publication. Incandola, from CMS, adds: The results are preliminary but the 5 sigma signal at around 125 GeV we're seeing is dramatic. This is indeed a new particle. We know it must be a boson and it's the heaviest boson ever found. The implications are very significant and it is precisely for this reason that we must be extremely diligent in all of our studies and cross-checks. And Sergio Bertolucci, research director of CERN, says: It's hard not to get excited by these results. We stated last year that in 2012 we would either find a new Higgs-like particle or exclude the existence of the Standard Model Higgs.

With all the necessary caution, it looks to me that we are at a branching point: the observation of this new particle indicates the path for the future towards a more detailed understanding of what we're seeing in the data. The results presented today are labelled preliminary, the statement adds. They are based on data collected in 2011 and 2012, with the 2012 data still under analysis. Publication of the analyses shown today is expected around the end of July. A more complete picture of today's observations will emerge later this year after the LHC provides the experiments with more data. The next step will be to determine the precise nature of the particle and its significance for our understanding of the universe. Are its properties as expected for the long-sought Higgs boson, the final missing ingredient in the Standard Model of particle physics? Or is it something more exotic? The Standard Model describes the fundamental particles from which we, and every visible thing in the universe, are made, and the forces acting between them. All the matter that we can see, however, appears to be no more than about 4% of the total.

A more exotic version of the Higgs particle could be a bridge to understanding the 96% of the universe that remains obscure. Positive identification of the new particle's characteristics will take considerable time and data. But whatever form the Higgs particle takes, our knowledge of the fundamental structure of matter is about to take a major step forward. 9.21am: First reaction from Peter Higgs has just landed in my inbox. According to a statement sent by Edinburgh University, the physicist says he is "astounded" at the speed with which the results have emerged and is preparing to celebrate. Scientists at CERN are to be congratulated on today's results, which are a great achievement for the Large Hadron Collider and other experiments leading up to this. I am astounded at the amazing speed with which these results have emerged. They are a testament to the expertise of the researchers and the elaborate technologies in place. I never expected this to happen in my lifetime and shall be asking my family to put some champagne in the fridge. Participants applaud after the presentation of the Atlas experiments. Photograph: Denis Balibouse/AP 9.23am: Gianotti is still presenting Atlas's results but the reaction is already pouring in.

Here's are the first few paragraphs from Ian Sample's first take on today's momentous announcement. There comes a time in a scientist's life when the weight of evidence can no longer be ignored. That moment came today for physicists at Cern , home of the Large Hadron Collider near Geneva, who announced overwhelming evidence for the obscure but profoundly important Higgs boson, the particle that sparked the greatest hunt in modern science. In presentations given to a packed auditorium at the laboratory on Wednesday morning, and webcast around the world, the leaders of two research teams, who worked independently of each other, said they had spotted a new particle amid the microscopic flashes of primordial fire created inside the world's most powerful atom smasher. Cern stopped short of claiming official discovery of the Higgs boson, even as many physicists conceded the evidence was now so compelling they had surely found the missing particle. Formal confirmation of the discovery is expected within months, though it could take several years for scientists to work out whether they have found the simplest kind of Higgs particle that theories predict, or part of a more complex picture: for example, one of a larger family of Higgs bosons.

The discovery of more than one kind of Higgs particle would open the door to an entirely new realm of physics. 9.29am: "#CERN" is trending worldwide. As is #Higgs, and #GodParticle (sorry), and ATLAS. No #Higgsteria yet though, despite a valiant effort by social media types. 9.32am: Today's discovery is "unbelievably exciting", according to Harvard physicist Lisa Randall. She told the Guardian: I really didn't expect this. They got enough data and improved analysis to the point where we know about a new particle months before I expected (based on asking lots of people)! It is unbelievably exciting. Tommaso Dorigo , a scientist on the CMS experimental team at Cern, had this evaluation for Ian over in Geneva: Is it a Higgs boson or not? Well, it has been found using techniques tuned for the Standard Model Higgs. A different object might have stepped in, but it is quite unlikely in my humble opinion. A representation of traces of a proton-proton collision in the search for the Higgs boson, released by Cern.

Photograph: AFP/Getty Images 9.35am: Cheers and applause for Gianotti now. ATLAS - round of applause + cheers. 5 sigma discovery at 126.5 GeV It's like zoologists trying to determine if they've discovered a new species of butterfly by looking at a meadow through binoculars. From 16 miles away. Shiv Malik Our very own Shiv Malik has also put his scientist's hat on to try to explain One talking point is how reliable the results are. This is based on how certain physicists are about the data they have. The way this is normally measured is through standard deviation i.e. the 1-5 sigma that we've been hearing about. This handy explainer graphically shows what deviation is on a usual distribution graph or a bell curve, where most results are based around the middle but there are also some extreme results at either end. Something like plotting height amongst a big population of 35 year old males would give you a bell curve graph like this. Tall and short at either end but most people are say, 5 Ft 8". Five sigma from the standard deviation therefore means many steps away from the norm.

In terms of height it would be say, adults males who are either 2ft or 7ft tall i.e. very unusual. But now reverse engineer the exercise. Imagine you are looking at 7ft people and you want to know how likely it is that this is a strange result from the middle or the norm. How would you work this out? How would you come up with a number to represent this? Well, looking at the data, plotting the graph, you could say that 7ft adult males represent 5 sigma deviation from the norm, so you are pretty sure that this is an odd or unusual result and therefore worth being (statistically speaking) interested about. This is what those at CERN have been saying today. 11.00am: As the journalists in Geneva continue to beg the Cern guys for replies they can understand, here at the Guardian we are begging you to help us explain the Higgs boson. My colleagues write: Can you help us break it down into even simpler terms? If you're a scientist, a teacher or a physics fan with a knack for explaining big ideas and small particles, we're imploring you to help.

• How would you explain Higgs boson to a 7-year-old? • What analogy best explains what's happening at Cern? • Can it be described in 200 words? 11.09am: A bold Reuters journalist just asked them to provide their own metaphors for the Higgs boson. Alas. "The podium is metaphorless," replied Heuer. British physicist Peter Higgs (right) speaks with Belgium physicist Francois Englert. Photograph: Fabrice Coffrini/AFP/Getty Images 11.18am: Ok, that's that. The press conference is over. Throughout, Peter Higgs refused to make any comment other than to praise the achievement and to say he was making no further comment. He obviously didn't want to hog the limelight, which will only endear him further to his new legion of Twitter fans. 11.25am: On a lighter note, here's a storify of Twitter jokes about the Higgs boson as collated by Hannah Waldram. Sure there are plenty more to come, so tweet your best to @guardian on #higgsjokes.

11.34am: You can now read Ian Sample's excellent take on this morning's announcement at length here. And, for those of who still a little in the dark, check out this fun explainer video by PHD Comics on Vimeo. Thanks to Koos Fuite below the line for the spot. 11.55am: My colleagues Hannah and Laura have been collating some of the lovely explanations coming in in response to our plea to explain the Higgs boson in a way a 7-year-old child would understand. My favourite- and certainly the most inventive- is egorulz's effort below the line. Once upon a time in a far away land, there were two rival families: Fermions and Bosons. Fermions were famous for their peculiar half spin dance. Electrons, protons and quarks were all Fermions. The Bosons however were into full spinning though and despised half spin. Photons and Gluons were Bosons. It was rumored that Bosons had a long lost elder brother called Higgs Boson who had been missing for a long long time. One day a wise old man came to the land of the feuding families.

He told them they should stop quaerlling over half spin and full spin, since they all used to be the same, and that they all used to be massless. The old man said that, in the beginning of time when the universe was created, everyone was born the same, but then they were immersed in a mysterious field called the higgs field making each of them different except for Photons who remained the same. He said this mysterious field was made up of the Higgs Boson - the long lost Boson brother. The families ofcourse refused to believe all this hogwash, and so the old man set about trying to prove his story and bring the Higgs Boson out of his hiding place. To do this he asked for help from the scientists at CERN. The family feud is coming to an end, at last. 12.03pm: The science community seems agreed: this is a big moment. But many, like Heuer, are cautioning that this could be just the beginning. Dr Roberto Trotta, Lecturer in Cosmology at Imperial College London, has this to say, according to the Science Media Centre.

This could be just the first step towards uncovering a completely new layer of reality - the Higgs might lead to the discovery of supersymmetry: the notion that for every known particle there exist a super-particle with a much larger mass. And if supersymmetry is real, then we are on our way to finally crack the mystery of the dark matter in the Universe. Dark matter might be 'the last Highlander' of all supersymmetric particles, the only surviving 'sparticle' from the Big Bang. And we might be on the verge of hunting it down at the LHC. Professor John Womersley, STFC Chief Executive, said: Obviously having found a new particle, there is still much, much more to do at the LHC – we need to confirm that this new particle is the reason some particles have tangible mass while others are insubstantial – as proposed by Peter Higgs and other scientists, who predicted that a previously unknown particle must exist for our current understanding of the Universe to work. And, for Professor Valentin Khoze, Director of Durham University's Institute for Particle Physics Phenomenology (IPPP), this discovery is just opening the door to others that could be even more exciting.

The second part of the story about the Higgs particle is even more exciting as it provides us with a window to new physics - a tool for the exploration of the truly unknown. The next stage will be a detailed and careful study of its properties. Successful completion of this second stage will bring us closer to uncovering new physics, explaining dark matter and other mysteries of the Universe. 12.09pm: Ian Sample has this thought for us: Stephen Hawking bet Gordy Kane (UMICH) $100 that the Higgs would never be found at Cern. Wonder if he's conceded defeat? #Higgs #ichep2012 Elswick physicist thrilled with God particle discovery - The Journal Elswick physicist thrilled with God particle discovery 08:22, 5 Jul 2012 WALKING in the mountains almost 50 years ago, Newcastle-born Peter Higgs may not have realised that one day his name would be on the lips of half the world. Share Professor Peter Higgs at a press conference at Edinburgh University WALKING in the mountains almost 50 years ago, Newcastle-born Peter Higgs may not have realised that one day his name would be on the lips of half the world.

Even a few years ago, the quiet and unassuming physicist was a virtual unknown outside academic circles, with his greatest work better known by its more media-friendly moniker, the God particle. But the former physics professor, who is now 84, wept yesterday at the globe’s biggest laboratory when it was announced that his fellow scientists have seemingly proved him right, finding evidence of what they think is the “glue” that holds the universe together. “I’m rather surprised that it happened in my lifetime,” said the son of a BBC sound engineer who grew up in Elswick, in Newcastle’s West End. “I certainly had no idea it would happen in my lifetime at the beginning, more than 40 years ago, because at the beginning people had no idea about where to look for it, so it’s really amazing for me. “I think it shows amazing dedication by the young people involved with these colossal collaborations to persist in this way, on what is a really a very difficult task.

I congratulate them.” In 1964, while walking through the Cairngorms in Scotland, Prof Higgs came up with the idea that particles – also known as bosons – derive their mass from the speed at which they pass through a field of much smaller particles, which were given the name Higgs bosons. The idea became one of the main tenets on which quantum physicists built the Standard Model of how the universe works and scientists have spent nearly 50 years hunting down the elusive proof that the Higgs boson exists. Such efforts took a leap forward with the opening in 2008 at CERN – the European Laboratory for Particle Physics – of the Large Hadron Collider, a 17-mile long, high energy particle accelerator that was constructed under the mountains of Switzerland. Among those putting forward their expertise to help devise and analyse the experiments at the LHC were members of Durham University’s Institute for Particle Physics Phenomenology. The group’s director, Professor Valentin Khoze, said the mounting evidence that the particle had been produced and detected was “a triumph for particle physics.” “Higgs boson play an absolutely vital role in our very understanding of fundamental physics,” he said.

“Without the Higgs particle, other particles such as electrons and quarks would be massless and the universe would not be what it is. “Now, with the amazing results from the LHC, we are finally starting to find the experimental evidence that the Higgs really exists.” But Prof Khoze said the work was far from over and, for scientists, the second stage of the story could be even more exciting than the first. “This discovery provides us with a window to new physics, a tool for the exploration of the truly unknown. “The next stage will be a detailed and careful study of its properties. Successful completion of this second stage will bring us closer to uncovering new physics, explaining dark matter and other mysteries of the universe.” The first suggestion that scientists may have found a Higgs-like particle came last December but, ever cautious – particularly in the wake of last year’s later- disproved claim from CERN that neutrinos had been observed travelling faster than light – the academics sifted through billions of tests worth of data to try to confirm their initial results.

Yesterday, they said two of the LHC’s giant detectors, CMS and Atlas, had delivered results that reached the definitive “five sigma” level of proof, when the likelihood of a statistical fluke is one in a million. Future research may uncover more than one Higgs boson, or find better ways of describing the universe than the Standard Model, which would have had to be torn up if the event the particle didn’t exist. One theory, called “supersymmetry”, claims more than five Higgs-like particles may be out there, each with completely different properties. Professor Jon Butterworth, from University College London, said regardless of the next step, right now he was just over the moon. “We don’t know exactly what we’ve discovered but it’s fundamental, new and exciting, and it looks like the Higgs boson,” he said. “I think it’s something so like the Standard Model Higgs that any differences will be incidental. We still need to see that it does the job the Higgs is there for, which is to give particles mass. I feel absolutely elated.” Even Prime Minister David Cameron passed on his congratulations. “It is a very big step forward and we should congratulate everyone involved,” he said.

Page 2 - Atoms, protons and pasties >> Atoms, protons and pasties TO make matter you only need three things – electrons, an up quark and a down quark. Using the quarks you can make protons and neutrons, and when you put a few of those together with electrons you get an atom. However, scientists have so far discovered 12 sub-atomic particles and there could be many more. To try and make sense of what all these particles are for, scientists have organised them depending on how they behave, almost like the periodic table of elements. And to try to find if there are any other varieties they use a particle accelerator to smash protons together. But when you smash particles together what you get out isn’t necessarily what you put in, as the particles turn into a kind of energy - known as a force-carrying boson – and that can be used to make any other particle for which you have enough energy. Put simply, it’s like two people walking into Greggs, one with enough money for a cheese and onion pasty and the other enough for a packet of jam doughnuts. The pair bump into each other and drop their wallets, with the money going everywhere.

The wallets are the protons and the coins inside the bosons. Now with the combined coins the pair can buy anything up to the value of the cash, be that one chicken tandoori sandwich or a steak bake, sausage roll and a cupcake. The more money - energy - in the two wallets to begin with, the more possible outcomes - to the point where if there’s enough money the duo might even get to go and buy something off the completely different menu in the McDonalds next door. What Peter Higgs predicted was given enough energy you would see the presence of a particle called the Higgs Boson, which gives other particles mass. What is mass? To most people mass means the amount of "stuff" something has to it - but an electron has mass but no volume, so there’s no "stuff" in it. So the best way to think of mass is probably just as a characteristic of a particle, like charge. And when two things have mass they will attract together. Where does the mass come from? Imagine a children’s ball pool that covers the entire universe. Every particle feels the ball pool as it moves, but some can pass through it faster than others.

Those that pass through it more quickly have a small mass, while those slowed down a lot have a large mass. Why has it taken so long to find this Higgs-like particle? Well if you smash two particles together and make a Higgs it may go on to form, say, two bottom quarks. But like the Greggs analogy there’s many ways to afford a pepperoni slice, so buying the pizza isn’t an indication of the coinage used. Why hasn’t it been seen until now? The intermediate stage of the process in which the particles become energy before turning back into particles might only appear for 0.00000000000000000000001 seconds and obviously you only get one chance to spot it. To reach this stage has required the Large Hadron Collider to smash protons together millions of times, every day, for years and then a small army of scientists to analyse the results and look for the tiny variance that proves the existence of a particle in a Higgs-like energy state. Mountain trek led to moment of inspiration UNTIL recently, Professor Peter Higgs was as unknown to most of the world as the famous particle that bears his name.

Today the quiet physicist, now retired from the University of Edinburgh, is fast becoming a global celebrity as creator of the theory behind the God particle. And the man born in Newcastle in 1929, the son of a BBC sound engineer, could now be eligible for a Nobel Prize. Prof Higgs, 83, has been waiting since 1964 for science to catch up with his ideas about the Higgs boson. It was in that year he dreamed up the concept in a moment of inspiration while walking in the Cairngorms. Two scientific papers followed, the second of which was initially rejected and then finally published in the respected journal Physical Review Letters. Prof Higgs’s groundbreaking proposal was that particles acquire mass by interacting with an all-pervading field spread throughout the universe. The more they interact, the more massive and heavy they become. A "boson" particle was needed to carry and transmit the effect of the field – the Higgs boson. After his family moved to Bristol, he proved a brilliant pupil at Cotham Grammar School before going on to read theoretical physics at King’s College London.

He was awarded first-class honours in 1950, and after failing to secure a lectureship at King’s College, set off for Scotland. In 2006, he retired from the University of Edinburgh, assuming the title of emeritus professor. Never one to blow his own trumpet, Prof Higgs is described by friends and colleagues as very unassuming and shy. Some believe his retiring nature might even have held back his career. Now, despite his best efforts to keep a low profile, the spotlight will be fixed on him for some time. 'Nice to be right', says Higgs after particle milestone (Update) 'Nice to be right', says Higgs after particle milestone (Update) July 6, 2012 British scientist Peter Higgs poses for pictures after addressing a press conference at the University of Edinburgh in Scotland. Higgs who gave his name to what is likely to be the Higgs boson particle spoke of his delight at the discovery, saying it was "nice to be right sometimes". The British scientist who gave his name to the Higgs boson particle spoke Friday of his delight after researchers affirmed its existence, saying it was "nice to be right sometimes".

Professor Peter Higgs was making his first detailed public comments since researchers at the European Organisation for Nuclear Research (CERN) announced Wednesday they believe they have found the sub-atomic particle thought to confer mass on matter. The announcement came following nearly 50 years of research after Higgs published the conceptual groundwork for the elusive boson, dubbed the "God particle" because it is powerful and everywhere in 1964. Asked at a press conference at Edinburgh University if he now felt a sense of vindication, Higgs said: "It's very nice to be right sometimes... it has certainly been a long wait." The 83-year-old also brushed off suggestions he would now be in the running for a Nobel Prize as a result of the discovery. "I don't know, I don't have close friends on the Nobel committee," he said, when questioned about an honour which academics including Professor Stephen Hawking have suggested he should receive. He also declined to comment on whether those awarding the Nobel Prize should change its rules so that more than three people can share the award. This would allow the committee to recognise his work alongside that of the five others with whom he worked most closely on his research.

"It remains for the Nobel committee if they are interested in this result to see if they really have a problem," Higgs said. Later, Higgs's friend and colleague Alan Walker recounted the low-key celebration they held after learning of the breakthrough, one of the most important scientific discoveries of recent years. Walker said he and Higgs were flying home from CERN in Geneva this week on budget airline easyJet when he offered Higgs a glass of Prosecco sparkling wine so they could toast the discovery. Higgs replied: "'I'd rather have a beer' and popped a can of London Pride," Walker said. Higgs added that he has not contributed to theoretical physics since the mid-1980s, when he became "too old". "I couldn't, at that age, acquire sufficient new mathematical skills which were needed to contribute, so I stopped," he said. Asked what he was going to do next, Higgs told reporters he was simply looking forward to continuing his retirement. "The only problem, I think, will be that I shall have to dodge the press," he quipped. Meanwhile, Edinburgh University, where he is Emeritus Professor of Physics, announced Friday that it was naming a new centre for theoretical physics after Higgs.

Hawking says he lost $100 bet over Higgs discovery July 4, 2012 Renowned British physicist Stephen Hawking said Wednesday the Nobel Prize should be given to Peter Higgs, the man who gave his name to the Higgs boson particle. For India, 'God particle' is as much boson as Higgs July 4, 2012 The release Wednesday of dramatic new data pointing to the existence of the Higgs boson "God particle" sent a special flutter of pride, mixed with frustration, through India's scientific community. Shy physicist whose name will live on in Higgs boson July 4, 2012 Forty-eight years ago, British scientist Peter Higgs had a eureka moment when he realised there could be a particle that confers mass, one of the greatest puzzles in physics. CERN to give update on search for Higgs boson June 22, 2012 The European Organisation for Nuclear Research said Friday it may announce next month whether tests with its atom-smasher have found the elusive "God particle".

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Question: Which Edinburgh physicist has given his name to a sub-atomic particle which has not yet been observed?
Answer: (Peter) Higgs