British scientist Peter Higgs dreamt up a theory explaining the tiny particles that make up everything, including you, decades ago. At last he’s set to be proved right.
Peter Higgs remembers the day everything suddenly began to make sense. “It was July 16, 1964, when some new research papers arrived. I looked at one, realised what it meant and then jumped up and shouted out loud: ‘Oh shit’.”
For years his colleagues had been working on theories about the building blocks of the universe – and Higgs had disagreed with them all. The trouble was, he’d had no better suggestions.
Now he had an idea and spent the weekend mulling it over. “When I came back to work on Monday, I sat down and wrote a new paper as fast as I could,” he recalled in an interview last week.
“I thought it was very important. I had knocked a hole in the existing theorems and suggested an alternative.”
Higgs got into print in just 11 days but was largely ignored. So he rapidly wrote a second paper. He sent it to an editor at the European Organisation for Nuclear Research, known as Cern, only to have it dismissed as out of hand. “I was indignant,” said Higgs, “but I also thought I was right, so I set to work to spice it up.” He added a final paragraph setting out how his theory predicted the existence of an entirely new type of tiny particle called scalar and vector bosons. To particle physicists, it was revolutionary. Although impenetrable to laymen, such theoretical research has many benefits, if only because it is tested by machines that push science into new realms. The spin-offs from Cern, for example, include the internet, medical scanners and, more recently, new cancer therapies.
What Higgs had done was to predict how matter could acquire mass – which we perceive as weight.
This was a problem that had baffled scientists and Higgs’s solution brought him fame beyond the dreams of most physicists. However, it was a bittersweet triumph: the pursuit helped ruin his personal life, which in turn sent his research career into limbo.
Only now, 44 years on, is he about to find out whether it was all worth it. On September 10, scientists at Cern will switch on the Large Hadron Collider (LHC), the most powerful “particle-smasher” built, to test Higgs’s ideas. If it finds the tiny particles he predicted, it will confirm that our understanding of the structure of the universe is on the right track. If it fails, it will raise even greater questions.
Higgs is excited at either prospect. “It will almost be a relief when they find it,” he said. “It could even be more exciting if they don’t because it means all our ideas are wrong and we have to start again.”
It might seem obvious why you weigh what you do, but at the atomic level it is far from clear. On the face of it, the mass of a chunk of matter ought to reflect the combined mass of the atoms in it.
However, the theories prevailing in Higgs’s day suggested the opposite. They showed that the tiniest components of atoms – known as quarks and leptons – ought to have no mass at all. This was clearly wrong. What Higgs wanted to know was, how does such matter acquire mass?
Higgs suggested that all space is permeated by a “field” that interacts with the particles within it, giving them mass. One analogy is to imagine a room full of people milling around. A celebrity enters and, as he or she moves through the crowd, people cluster around; suddenly the celebrity particle has mass.
Higgs predicted that some types of particle would react more strongly with the field than others. Others such as photons, the particles that make up light, would not interact at all. That is why they have no mass and hurtle around the universe unimpeded.
Finally, said Higgs, his invisible field should create particles of its own – the famous boson – that could be spotted with sufficiently powerful equipment. But at the time, none was available.
Soon after publishing his ideas, Higgs began an exhausting round of visits to universities and academic conferences. He also began work on a third and much longer paper that would back up his theories. The pressures took their toll.
When his first son was born, he was cloistered in a university library 100 miles away. When he was at home he spent much of his time working – too much. In 1972 his wife decided to end their marriage.
“We split up because I had put my science career above the family,” he said, still emotional at the memory. “One time I backed out of a family holiday when we were meant to be going to America. Then I got on a plane and went to a conference. Jodie, my wife, just lost touch with what I was doing.”
For Higgs the end of the marriage was more than a personal disaster. It threw his research into a spin. “After the break-up of my marriage, I think I just lost touch with the things I should have been learning about just to follow up my own work. I couldn’t keep up.” Eventually Edinburgh University awarded Higgs a professorship and he devoted more of his time to teaching and administration. Later he and Jodie, who died earlier this year, became good friends again.
Throughout the difficult years, however, Higgs could take comfort from the growing recognition of his work. Dr John Ellis, a senior scientist at Cern, said: “In just a few years of the early 1970s we gained a much greater understanding of the elementary particles that make up matter – and the relationships between them.
“Those discoveries not only helped build the standard model [of particle physics], they also showed that Higgs’s ideas were crucial to the whole thing.”
Since then the hunt for the Higgs boson has intensified. In the 1980s, hopes rested on the Large Electron-Positron Collider (LEP), which accelerated particles in opposite directions around a 17-mile diameter ring before smashing them into each other.
The LEP made many discoveries, but it was not powerful enough to find the Higgs boson. So it was dismantled to allow the LHC to be built in the same tunnel. Is it worth £2.2 billion? Cern’s researchers claim they have given good value for money, quite apart from the physics research.
Perhaps the centre’s best-known spin-off is the world wide web – invented by Tim Berners-Lee to help researchers share information generated by the LEP. Cern is now building a system, called the Grid, to store and share the gigantic quantities of data the LHC will generate. Could it replace or improve the web? Time will tell.
The Grid technology is already being used for a Europe-wide system for sharing information on mammo-grams, the x-ray images taken in screening women for breast cancer. Cern is also working on so-called hadron therapy, where accelerator technology is used to kill cancer tumours with doses of special particles.
Last April Higgs paid his first visit to the collider and professes himself stunned. “I was staggered by the scale of the whole thing,” he said.
What impressed him most was its sheer power – designed to accelerate beams of protons to more than 99.99999% of the speed of light. At four points around the tunnel, counter-rotating beams will be smashed into each other, showering sub-atomic debris in all directions. Hopefully this will include Higgs bosons.
The trickiest part will be detecting them. Higgs bosons are predicted to break down after less than a millionth of a trillionth of a second. For Higgs, now 79, the long wait to observe that moment is drawing to a close. If the particles are found, he may well win a Nobel prize.
Dr Lyn Evans, Cern’s LHC project leader, said: “We are completing the work that Peter Higgs started all those years ago. I just hope we can show him the results.”
August 17, 2008
Source: The Times