Tag Archives: Higgs Boson

Peter Higgs: The Life Scientific

Quantum physicist and broadcaster Jim Al-Khalili blogs on interviewing Peter Higgs for the new series of The Life Scientific on BBC Radio 4. Discover more about the LHC, particle physics and the search for the Higgs boson in our Collider exhibition

I love name dropping about some of the science superstars I’ve interviewed on The Life Scientific. ”Richard Dawkins was quite charming on the programme, you know”, or “James Lovelock is as sharp as ever”, and so on. So imagine my excitement when I heard I would be interviewing the ultimate science celebrity Peter Higgs.

When I discovered we had secured him for the first programme in the new 2014 series, I knew I had to get something more out of him than to simply regurgitate the popular account of the man as shy, modest and unassuming, and still awkward about having a fundamental particle named after him; or how the Nobel committee were unable to get hold of him on the day of the announcement because he had obliviously wandered off to have lunch with friends.

This was an opportunity for two theoretical physicists – OK, one who has a Nobel Prize to his name and one who doesn’t, but let’s not split hairs here – to chat about the thrill of discovery and to peek into the workings of nature, whilst the outside world listened in.

A couple of Bosons: Peter Higgs with Jim Al-Khalili

A couple of Bosons: Peter Higgs with Jim Al-Khalili. Credit: Charlie Chan

You can listen to the programme from 18 February, but here are a few extracts to whet your appetite.

Can you explain the Higgs mechanism in 30 seconds?

At some point in the programme, inevitably, I had to ask Peter to explain the Higgs mechanism and Higgs field (both more fundamental concepts than the Higgs boson). He gave a beautifully articulate and clear explanation, but I then thought I should ask him to give the ‘idiot’s guide to the Higgs’, just to cover all bases. Here’s how that went:

‘The Boson that Bears my Name’

Working alone in Edinburgh in the sixties, Peter Higgs was considered ‘a bit of a crank’. “No-one wanted to work with me”, he says. In 1964, he predicted the possible existence of a new kind of boson, but at the time there was little interest in this now much-celebrated insight. And in the years that followed, Peter Higgs himself failed to realise the full significance of his theory, which would later transform particle physics.

In July 2012, scientists at the Large Hadron Collider at CERN confirmed that the Higgs boson had indeed been found and Peter Higgs shot to fame. This ephemeral speck of elusive energy is now the subject of car adverts, countless jokes, museum exhibitions and even a song by Nick Cave called the Higgs Boson Blues. But Higgs has always called it the scalar boson or, jokingly, ‘the boson that bears my name’ and remains genuinely embarrassed that it is named after him alone.

In fact, three different research groups, working independently, published very similar papers in 1964 describing what’s now known as the Higgs mechanism. And Higgs told me he’s surprised that another British physicist, Tom Kibble from Imperial College, London didn’t share the 2013 Nobel Prize for Physics, along with him and Belgian physicist, Francois Englert.

On fame
When the 2013 Nobel Prize winners were announced, Peter was famously elusive (much to the frustration of the world’s media). Most people romanticised that he was blissfully unaware of all the fuss or just not that interested. These days, he’s constantly being stopped in the street and asked for autographs, so I asked him whether he enjoyed being famous:

Physics post-Higgs
With the discovery of the Higgs finally ticked off our to-do list, attention is turning to the next challenge: to find a new family of particles predicted by our current front-runner theory, called supersymmetry. Higgs would ‘like this theory to be right’ because it is the only way theorists have at the moment of incorporating the force of gravity into the grand scheme of things.

But what if the Large Hadron Collider doesn’t reveal any new particles? Will we have to build an even bigger machine that smashes subatomic particles together with ever-greater energy? In fact, Peter Higgs believes that the next big breakthrough may well come from a different direction altogether, for example by studying the behaviour of neutrinos, the elusive particles believed the be the most common in the Universe, which, as Higgs admits, “is not the sort of thing the Large Hadron Collider is good for”.

When it started up in 2008, physicists would not have dreamt of asking for anything bigger than the Large Hadron Colider. But today one hears serious talk of designing a machine that might one day succeed it. One candidate is the somewhat unimaginatively named Very Large Hadron Collider. Such a machine would dwarf the Large Hadron Collider. It would collide protons at seven times higher energy than the maximum the Large Hadron Collider is able to reach. And it would require a tunnel 100 km in circumference. Of course this is not the only proposal on the table and there are plenty of other ideas floating about – none of which come cheap, naturally.

There are certainly plenty more deep mysteries to solve, from the nature of dark matter and dark energy to where all the antimatter has gone, and we will undoubtedly find the answers (oh, the delicious arrogance of science). Let’s just hope we don’t have to wait as long as Peter Higgs did.

Keen to discover more? You can listen to Peter Higgs on BBC Radio 4′s The Life Scientific (first broadcast 9am on 18 February) and visit the Collider exhibition at the Science Museum until 5 May 2014. 

Story of the Search for the Higgs Boson wins Royal Society Prize

Will Stanley, Science Museum Press Officer, blogs on the latest winner of the 2013 Royal Society Winton Prize for Science Books.

Theoretical physicist, presenter and author, Sean Carroll, has won the world’s most prestigious science book prize, with his story of the search for the elusive Higgs boson.

Carroll’s The Particle at the End of the Universe (OneWorld Publications) was announced as the winner of the 2013 Royal Society Winton Prize for Science Books last night at the Royal Society in London.

The £25,000 prize was awarded by Sir Paul Nurse, Nobel Prize-winning President of the Royal Society, with comedian and TV presenter Dara Ó Briain hosting the event. Speaking after winning the prize, Carroll said, “I feel enormous gratitude towards the thousands of physicists at the Large Hadron Collider and the millions of people who express their love for science everyday!”

This is a timely win for Caroll, with the discovery of the Higgs Boson in 2012 and last month’s Nobel Prize for Physics awarded to Peter Higgs and François Englert for their theoretical prediction of the Higgs boson. The Science Museum is also telling the story of the world’s greatest experiment and the hunt for the Higgs boson in a new exhibition, Collider.

Peter Higgs and Stephen Hawking in the Collider exhibition.

Peter Higgs and Stephen Hawking in the Collider exhibition.

Judges for the 2013 Royal Society Winton Prize for Science Books included impressionist Jon Culshaw, novelist Joanne Harris, journalist Lucy Siegle and Dr Emily Flashman, Royal Society Dorothy Hodgkin Fellow at University of Oxford.

The panel was chaired by Professor Uta Frith DBE FBA FRS, Emeritus Professor of Cognitive Development at University College London, who described the book as “an exceptional example of the genre and a real rock star of a book.” Frith went on to explain, “Though it’s a topic that has been tackled many times before, Carroll writes with an energy that propels readers along and fills them with his own passion. There’s no doubt that this is an important, enduring piece of literature.”

Carroll’s telling of ‘the greatest science story of our time saw off strong competition from a riveting shortlist of authors:

  • Bird Sense by Tim Birkhead, published by Bloomsbury
  • The Particle at the End of the Universe by Sean Carroll, published by OneWorld Publications
  • Cells to Civilizations by Enrico Coen, published by Princeton University Press
  • Pieces of Light by Charles Fernyhough, published by Profile Books
  • The Book of Barely Imagined Beings by Caspar Henderson, published by Granta
  • Ocean of Life by Callum Roberts, published by Allen Lane (Penguin Books)

If you would like to read more of these books, the Royal Society have published the first chapter of each book here.

Now in its 25th year, the book prize is sponsored by investment management company Winton Capital Management (supporters of our Collider exhibition). David Harding, Founder and Chairman of Winton Capital Management commented, “Sean Carroll’s book is a fascinating account of an inspiring scientific experiment that has brought thousands of people from different countries together to pursue knowledge in a collective way.”

Collider: Celebrating with Higgs and Hawking

This week we were joined by two of the world’s most eminent scientists, Stephen Hawking and Peter Higgs, to celebrate the opening of our Collider exhibition.

Peter Higgs and Stephen Hawking in the Collider exhibition.

Peter Higgs and Stephen Hawking in the Collider exhibition.

The exhibition, open until May 2014, explores the people, science and engineering behind the largest scientific experiment ever constructed, the Large Hadron Collider at CERN.

After a packed event in Parliament on Monday evening (more about that here), Higgs and Hawking joined us for a full day of public events on Tuesday.

The day began with Professor Peter Higgs answering questions from a lucky group of students from across the UK in our IMAX theatre – with thousands more watching the Guardian live stream online.

Higgs talked about his scientific hero Paul Dirac (who went to Peter’s school), being nominated for the Nobel Prize and whether discovering the Higgs boson was a good thing for physics. “Do you expect me to say it’s a bad thing,” joked Peter.

I always found physics rather dull at school. Chemistry was far more interesting – Peter Higgs.

The afternoon featured a spectacular double-bill of science and culture, with novelist Ian McEwan and theoretical physicist Nima Arkani-Hamed in conversation and an audience with Stephen Hawking.

Presented by broadcaster Martha Kearney, McEwan and Arkani-Hamed shared their thoughts on similarities and differences between the two cultures. Professor Arkani-Hamed explained that the gulf between arts and science is one of language, often mathematics, with McEwan discussing the obsessive element in science – the pursuit of something larger than ourselves – and it’s similarity to the arts.

I like to think of science as just one part of organised human curiosity – Ian McEwan. 

It was a very rare treat, and a huge honour, to journey into time and space with Stephen Hawking. Stephen shared that the Science Museum was one of his favourite places, “I have been coming here for decades. And that simple fact, in itself, tells quite a story.”

He went on to discuss his early work on black holes (Hawking would like the formula he wrote to be on his memorial) and the information they contain, “Information is not lost in black holes, it is just not returned in a useful way. Like burning an encyclopaedia, it’s hard to read.”

Hawking finished his talk with a plea to us all to be curious.

“The fact that we humans, who are ourselves mere collections of fundamental particles of nature, have been able to come this close to an understanding of the laws governing us, and our universe, is a great triumph.

So remember to look up at the stars and not down at your feet. Try to make sense of what you see and hold on to that childlike wonder about what makes the universe exist.”

As the day ended, the recent Nobel Prize winner and our most famous living scientist were given a tour of Collider.

Stephen Hawking views the Collider exhibition with curator Ali Boyle

Stephen Hawking views the Collider exhibition with curator Ali Boyle

We’ll leave the final word to Ali Boyle, the Collider exhibition curator.

Celebrate the Nobel Prize at the Science Museum

Roger Highfield, Director of External Affairs at the Science Museum, celebrates the 2013 Nobel Prize for Physics ahead of the opening of our Collider exhibition next month.      

Congratulations to Briton Peter Higgs and Belgian François Englert, winners of the 2013 Nobel Prize for Physics “for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN’s Large Hadron Collider.”

A few minutes ago, after an unusual delay, the Royal Swedish Academy of Sciences announced the winners of the physics prize in Stockholm, ending this chapter of the quest for new elementary particles, the greatest intellectual adventure to date.

Ian Blatchford, Director of the Science Museum, comments: “That it has taken decades to validate the existence of the Higgs Boson illustrates the remarkable vision of the theoretical work that Higgs, Francois Englert and others did with pen and paper half a century ago, one that launched an effort by  thousands of scientists and inspired a staggering feat of engineering in the guise of the Large Hadron Collider.

What is the Higgs? Here’s all you need to know, in just 90 seconds, from Harry Cliff, a Cambridge University physicist working on the LHCb experiment and the first Science Museum Fellow of Modern Science

Although the identity of the winners has been a closely-guarded secret, many have speculated that those who played a central role in discovery of the long-sought Higgs, notably the emeritus Edinburgh professor himself, were leading contenders for a place in history.

The Science Museum has been so confident that the Large Hadron Collider would change our view of nature that we have invested more than £1 million, and worked closely with the European Organization for Nuclear Research, CERN, to celebrate this epic undertaking with its new exhibition, Collider: step inside the world’s greatest experiment, which opens to the public on 13 November. 

Here Higgs explains how the Large Hadron Collider works during a visit to what is now Cotham School, Bristol, where he was once a pupil.

In July 2012, two separate research teams at CERN’s £5 billion Large Hadron Collider reported evidence of a new particle thought to be the Higgs boson, technically a ripple in an invisible energy field that gives most particles their mass.

This discovery represented the final piece of the Standard Model, a framework of theory developed in the late 20th century that describes the interactions of all known subatomic particles and forces, with the exception of gravity.

Nima Arkani-Hamed, a leading theoretical physicist at the Institute for Advanced Study in Princeton who will attend the launch of Collider, bet a year’s salary the Higgs will be found at the LHC.

Another speaker at the Collider launch, the world’s most famous scientist, Prof Stephen Hawking, lost a $100 bet he made against the discovery (though he is adamant that Higgs deserves the Nobel Prize).

Higgs, who refuses to gamble, told me just before the LHC powered up that he would have been puzzled and surprised if the LHC had failed in its particle quest. “If I’m wrong, I’ll be rather sad. If it is not found, I no longer understand what I think I understand.”

When Higgs was in the CERN auditorium last year to hear scientists tell the world about the discovery, he was caught reaching for a handkerchief and dabbing his eyes.  On the flight home, he celebrated this extraordinary achievement with a can of London Pride beer.

The Science Museum hoped to have the can, now deemed a piece of history Alas, Higgs had dumped it in the rubbish before we could collect it. However, the museum does possess the champagne bottle that Higgs emptied with his friends the night before the big announcement.

The champagne bottle Peter Higgs drank from, the night before the Higgs boson discovery was announced to the world. Credit: Science Museum

The champagne bottle Peter Higgs drank from, the night before the Higgs boson discovery was announced to the world. Credit: Science Museum

The modest 84-year-old  is now synonymous with the quest: the proposed particle was named the Higgs boson in 1972.

But there have been demands that the particle be renamed to acknowledge the work of others. Deciding who should share this Nobel has been further complicated because a maximum of three people only can be honoured (prompting many to question the criteria used by the Nobel committee).

The LHC, the world’s most powerful particle accelerator, is the cumulative endeavour of around ten thousand men and women from across the globe. In recognition of this the Collider exhibition will tell the behind-the-scenes story of the Higgs discovery from the viewpoint of a young PhD student given the awesome task of announcing the discovery to her colleagues (though fictional, the character is based on Mingming Yang of MIT who is attending the launch).

However, although one suggestion is to allow the two research teams who discovered the Higgs boson to share the accolade, the Nobel committee traditionally awards science prizes to individuals and not organizations (unlike the Nobel Peace Prize).

Instead, the Nobel committee honoured the theoreticians who first anticipated the existence of the Higgs.

Six scientists published the relevant papers in 1964 though, as Belgium’s Robert Brout died in 2011, there were five contenders (the Nobel Prize cannot be given posthumously).

In August 1964, François Englert from the Free University of Brussels with Brout, published their theory of particle masses. A month later, while working at Edinburgh University, Higgs published a separate paper on the topic, followed by another in October that was – crucially – the first to explicitly state the Standard Model required the existence of a new particle. In November 1964, American physicists Dick Hagen and Gerry Guralnik and British physicist Tom Kibble added to the discussion by publishing their own research on the topic.

Last week, Prof Brian Cox of Manchester University, who works at CERN, said it would be ‘odd and perverse’ not to give the Nobel to Peter Higgs, and also singled out Lyn ‘the atom’ Evans, the Welshman in charge of building the collider, as a candidate.

And the two likeliest winners were named as Peter Higgs – after whom the particle was named – and François Englert, according to a citation analysis by Thomson Reuters.

Today’s announcement marks the formal recognition of a profound advance in human understanding, the discovery of one of the keystones of what we now understand as the fundamental building blocks of nature.

Discover more about the Higgs boson and the world’s largest science experiment in our new exhibition, Collider, opening 13th November 2013.

Happy birthday, Z boson

Alice Lighton, content developer for our Collider exhibition, writes about the history of quantum physics. Collider: step inside the world’s greatest experiment opens in November 2013 with a behind-the-scenes look at the famous CERN particle physics laboratory. 

The air brimmed with excitement on this momentous day. The discovery of the particle confirmed a theory that had taken years to devise, and justified the toil of hundreds of scientists.

You might think I’m referring to the Higgs boson – the particle that explains mass, discovered at the LHC last year. But thirty years ago this month, another event shaped modern physics – the discovery of the Z boson.

In the 1960s, physicists predicted the Z and W bosons, as a way to link the electromagnetic and weak forces. There was plenty of evidence the theory was correct, but the lynchpin would be the discovery of the Z boson.

A section of the 4.3 mile-round Super Proton Synchrotron, at CERN near Geneva. Image: CERN

To make a Z boson, two particles are smashed together. The energy of the crash creates new, heavy particles. If a Z boson is produced, it sticks around for only a fraction of a second before it decays into other particles. To claim the prize of discovering the Z boson, physicists would need to be able to forensically reconstruct what happens in a collision, never seeing the Z directly.

Europe and America built machines to discover the Z, including the Super Proton Synchrotron (SPS) at CERN. “The idea of creating this massive object (the Z) and letting it decay…was a riveting idea (well at least for me in the late 1970s),” said Crispin Williams, a physicist who now works on the ALICE experiment at the LHC.

Two CERN physicists, effusive Italian Carlo Rubbia and Dutchman Simon Van der Meer, realised that to beat the firepower of the newly-opened Tevatron in Chicago, the SPS had to take risks. The pair devised an audacious plan; rather than fire beams onto a fixed object, they would collide two opposing beams, each only a hair’s width across and both travelling at almost the speed of light.

What’s more, one of the beams would be made of antimatter, which destroys ordinary matter. Creating and manipulating a beam of antimatter was a revolutionary concept.

Williams remembers when Rubbia and Van der Meer announced their plan to collide two beams. “This was to a packed auditorium at CERN and I suspect that most people thought he was out of his mind,” said Williams.

Rubbia and Van der Meer celebrate receiving a Nobel prize for their efforts. Image: CERN

Despite the technical challenge, the new collider worked. One visitor to CERN in 1982 described the intense excitement the new development created. “I went to the CERN cafeteria for a coffee and there I saw something that I had not noticed before. There was a monitor on the wall and people were watching the screen with great interest. The monitor was showing the rate of proton–antiproton collisions in CERN’s latest challenge – a bold venture designed to produce the intermediate bosons, W and Z.”

In January 1983, the risk-takers received their reward, when the W boson was discovered.  On 1st June 1983, scientists at CERN announced they had seen five Z bosons in their detectors.

The tracks left by the decay of the Z boson in a detector. Image: UA1/CERN

The route to the discovery had revolutionised particle physics, with more intricate detectors and the ability to manipulate antimatter. For Williams, the discovery of the Higgs boson was much less elegant. “In comparison the Higgs at the LHC is just brute force,” he said.  “Maybe I am just getting old and cynical: and I look back at the Z discovery through rose tinted glasses.”

View of the LHCb cavern

X-citing news from CERN

Dr. Harry Cliff, a Physicist working on the LHCb experiment and the first Science Museum Fellow of Modern Science, writes about a new discovery at CERN for our blog. A new Science Museum exhibition about the Large Hadron Collider will open in November 2013, showcasing particle detectors and the stories of scientific discoveries.

In 2003 physicists at the Belle experiment in Japan reported they had discovered a brand new particle.

Adding a new entry to the big book of particle physics is certainly satisfying, but not usually cause for much excitement. The discovery of the Higgs-like boson last year was an exception. After all, hundreds of particles have shown up in experiments over the last century. So many in fact, that they were often referred to, rather derisively, as a “zoo”.

The Large Hadron Collider at CERN. Image Credit: CERN

But the particle found at Belle was different.

It didn’t fit neatly into the picture painted by theory and there was no clear explanation for its origin. It was a bit of an enigma, and earned a suitably enigmatic name: the X particle.

Professor Val Gibson from the University of Cambridge told me that she and her colleagues “have been mesmerized” about the identify this mysterious particle for the last ten years.

The Particle Zoo

The vast majority of the particles that make up the particle zoo are not fundamental; in other words they are made up of smaller things and these things are fundamental particles called quarks. Six different types of quark have been discovered and they can form a large number of different combinations, explaining the particle zoo.

However, quarks only bind together in very specific ways. Two ways in fact. One option is a ménage à trois known as a baryon. Baryons include the proton and the neutron, the building blocks of the atomic nucleus. The other option is where a quark and an antiquark couple up to form a meson.

The X didn’t fit easily into either of these pictures. This generated a lot of excitement and there was speculation as to whether it could be an ordinary meson, or some new exotic combination involving four quarks, a tetraquark, or a “molecule” of two mesons stuck together.

If this were true it would be the first time such an exotic state had been definitively seen in nature.

The only way to tell would be to measure the quantum numbers of the X, three properties that give a clue to its internal structure. This hadn’t been possible, until now.

Exciting, Exotic X

Amid the hundreds of trillions of collisions generated by the Large Hadron Collider over the past three years physicists at the LHCb experiment (the experiment I work on) managed to pick out about 300 X particles.

View of the LHCb cavern

View of the LHCb cavern. Image credit: CERN

This week, they presented the first full measurement of the quantum numbers of the X, at a conference at La Thuile in Italy. The result was emphatic – the X is not a meson, it is something altogether more exotic.

LHCb physicist Dr Matt Needham told me that “this measurement is a great step forward in understanding this mysterious X” and a “very exciting result”. However, there is still work to be done.

“The real nature (of the X) is still unclear”. Whether it’s a tetraquark, meson molecule or something else entirely must now be determined.

His colleagues at LHCb will now search for signs of the X decaying in new ways to try to separate out the various different options. Although the Large Hadron Collider has now shut down for two years physicists at LHCb will have no shortage of data to work with. An unprecedented sample was collected during 2012, corresponding to 180 trillion collisions, each one producing hundreds of particles.

The true nature of this enigmatic particle may soon be known. Whatever the result, we have now had our first glimpse of an altogether new state of matter. Finding out exactly what the X is will bring us deeper understanding of nature’s fundamental building blocks and the forces that bind them together.

Visitors to the Science Museum will have a chance to get up close and personal with the LHC at a new exhibition opening in November 2013. The exhibition will showcase real pieces of the LHC, including an intricate particle detector from the heart of the LHCb experiment.

A Higgs boson is produced in the ATLAS detector

The boring boson?

Last week scientists working on the Large Hadron Collider in Geneva updated their colleagues on the newly-discovered Higgs boson. They revealed what they now know about the particle – and so far, it is behaving exactly as they expected. While this might seem like good news, for some people it is the opposite, because a well-behaved Higgs might rule out some intriguing new physics theories.

A Higgs boson is produced in the ATLAS detector

A Higgs boson is produced in the ATLAS detector

The Higgs – the particle which explains why others have mass – is incredibly unstable and only exists for a fraction of a second before decaying into other, more common particles. Any information about it comes second-hand from these other particles, and working out the properties is rather like putting together clues in a Sherlock Holmes tale, only with more mathematics.

Finding the Higgs in July was a wonderful coup for the LHC, but there now follows years of painstaking work to determine its precise properties. If the Higgs behaves even a smidgen differently from predictions, then it might point scientists in the direction of a new theory.

One particularly popular idea has the rather grand name of “supersymmetry”, which as we wrote on this blog last week, is looking less likely to be true.

There are lots of problems with current theories about the Universe – they don’t explain dark matter, and particle physics is completely incompatible with Einstein’s theories of gravity. Supersymmetry solves some of these issues in a whizz of complicated mathematics, but requires the existence of a whole family of new particles. If they exist, the Higgs’ properties should reveal them.

The results announced on Wednseday in Japan don’t lend the under-fire supersymmetry any more support. They suggest that so far, the Higgs behaves just as our current theory predicts it should. Specifically, when it decays, it turns into different types of particles at the rates we expect.

To some in the community, the Higgs’ conformity is rather disappointing.  But not all of the analysis was ready for the Japan conference and there is still uncertainty around the results that were announced, and supersymmetry still could work.

Even though the LHC has already analysed more data in two years than its predecessor managed in twenty, the measurements are not yet particularly precise, and the Higgs may still harbour surprises. The LHC still has not detected a Higgs decaying into quarks (the smallest unit of matter), for example – we just know that since we haven’t seen it yet, it can’t happen often. In other words: watch this space.

Visitors to the Science Museum will have a chance to get up close and personal with the LHC at a new exhibition opening in November 2013.