Stephen Hawking's £50 bet on the world, the universe and the God particle

From Times Online

September 9, 2008

When the world’s largest atom-smasher begins colliding particles in a few months time, there is just a chance that it might create a miniature black hole.

It would not destroy the Earth, as some alarmists would have it - but it would guarantee a Nobel prize for Professor Stephen Hawking, according to no less an authority than the great man himself.

As scientists make their final preparations to switch on the Large Hadron Collider (LHC) tomorrow morning at the CERN particle physics laboratory near Geneva, the world’s best-known living physicist said there would be “no doubt” he would win a Nobel if it produces a black hole that confirms his theories.

The Lucasian Professor of Mathematics at the University of Cambridge, however, is not expecting such a triumph. He calculates the chances of a black hole emerging from the LHC at less than one per cent. “If the LHC were to produce little black holes, I don’t think there’s any doubt I would get a Nobel prize, if they showed the properties I predict,” Professor Hawking told the Today programme. “However, I think the probability that the LHC has enough energy to create black holes is less than one per cent, so I’m not holding my breath.”

It is far more likely, indeed, that the LHC will cause him to lose a long-standing bet with Professor Gordy Kane, of the Michigan University, over the existence of the Higgs boson. Professor Hawking is not convinced that the so-called “God particle”, which theory suggests gives matter its mass, actually exists, and in 2000 he backed his judgement by making a $100 (£50) wager with Professor Kane, who thinks it will soon be found.

Should the Higgs bosun exist, it is almost certain that the LHC will identify it. “The LHC will increase the energy at which we can study particle interactions, by a factor of four,” Professor Hawking said. “According to present thinking, this should be enough to discover the Higgs particle, the particle that gives mass to all the other particles.

“I think it will be much more exciting if we don’t find the Higgs. That will show something is wrong, and we need to think again. I have a bet of $100 that we won’t find the Higgs.”

The discovery of the Higgs boson would almost certainly win a Nobel prize for its proposers – Professor Peter Higgs, of the University of Edinburgh, and two lesser-known Belgian physicists, Francois Englert and Robert Brout.

Professor Hawking’s claim to a Nobel prize rests on a different piece of theoretical physics: his 1974 proposition that black holes can emit radiation, despite their overwhelming gravitational pull. Though the idea was initially greeted with widespread scepticism, the concept of “Hawking radiation” is now generally accepted, though as with the Higgs boson, there is no direct evidence that it exists.

The LHC, which has cost upwards of £3.5 billion to build, might create miniature black holes that decay into Hawking radiation, as the professor proposed. It is uncertain, however, whether the accelerator will generate the vast energy that would be required.

Should a black hole arise, however, it would present no threat, as the same mathematics that suggests their creation is possible also requires that they would immediately decay.

“If the collisions in the LHC produced a micro black hole, and this is unlikely, it would just evaporate away again, producing a characteristic pattern of particles,” Professor Hawking said. “Collisions at these and greater energies occur millions of times a day in the Earth’s atmosphere, and nothing terrible happens.”

Two court cases have sought to stop scientists from switching on the LHC because of this imaginary risk. One has already been thrown out, and the other stands no chance of stopping the project.

At CERN tomorrow, scientists will make their first attempt to circulate a beam of protons around the entire 17-mile (27km) circumference of the accelerator, using powerful magnets to guide it around the ring’s eight sectors. Practice runs have already taken a beam around a few of these sectors, and engineers are confident of success today.

If all goes well, the team will then try to circulate a second beam in the opposite direction. Once the two beams are in place, the way will be clear to start colliding protons at low energies in order to calibrate the LHC’s four detectors.

Experimental collisions will begin later in the year, which is technically the first point at which a miniature black hole might be formed. It is more likely, but still improbable, when the LHC reaches its full collision energy next year.

Other possible discoveries from the LHC include supersymmetry, a theory that all particles have “super-partners” sometimes known as “sparticles”, and the nature of dark matter, a mysterious substance that makes up about a quarter of the mass of the Universe yet cannot be seen.

Professor Hawking said that the collider is among the greatest technological achievements of this age, and that such study of basic science might eventually have important practical spin-offs.

“Throughout history, people have studied pure science from a desire to understand the Universe, rather than for practical applications or commercial gain. But their discoveries have later turned out to have great practical benefits. It is difficult to see an economic return from research at the LHC, but that doesn’t mean there won’t be any."

He said that trying to choose between the importance of exploring space and running the LHC would be “like asking which of my children I would choose to sacrifice". “Both the LHC and the space programme are vital if the human race is not to stultify and eventually die out. Together, they cost less than one tenth of a per cent of world GDP. If the human race cannot afford that, it doesn’t deserve the epithet ‘human’.”

Ian Pearson, the science and innovation minister, said: “The UK is a world leader in science, which is why this Government has invested more than £500m in the construction of the Large Hadron Collider at CERN.”

Professor Keith Mason, chief executive of the Science and Technology Facilities Council, which funds the UK contribution, said: “This is a historic moment in science; the culmination of decades of work. I believe we are poised on the threshold of a new age of physics. Scientists waiting for the LHC dare to ask the biggest questions that exist in modern science. They want to test our understanding of the universe and find out if dark matter exists, whether the four dimensions of space-time are it or in fact there are eleven dimensions! They want to know why some particles have mass and some like particles of light, don’t. Using the four detectors at the LHC we will be able to look at these mysteries.”