A Brief History of Stephen Hawking's Gambling Problem

If there's one thing we've learned from the Higgs-Boson discovery, it's this: Always, always bet against Stephen Hawking.

The famed Cambridge University physicist had to cough up $100 to University of Michigan physicist Gordon L. Kane after European research center CERN announced last week that they'd found a subatomic speck that appears to be the Higgs boson, a particle that is thought to be the reason that other particles like electrons and protons have mass. Hawking bet Kane years ago that the Higgs boson would never be found.

Kane told Reuters on Monday that he was elated by the discovery and that winning the bet is a very nice frosting on the cake.

This isn't the first wager that Hawking has lost. The author of A Brief History of Time gave a baseball encyclopedia to California Institute of Technology physicist John Preskill after conceding that he was wrong about a quirk of physics called the black hole information paradox.

This paradox arises from the strange confluence of quantum mechanics and general relativity that occurs in black holes. It centers on all of the stuff that falls into a black hole -- is it completely destroyed or is it reformulated as the theoretical Hawking radiation emitted by a black hole as it evaporates?

Hawking had argued that if something, say, a baseball encyclopedia, went beyond the event horizon of a black hole, it was lost forever. But particle physicists like Preskill disagreed.

Perhaps information really can escape from a black hole, but we will not be able to understand just how the information escapes without deep new insights into the physics of processes in which both quantum effects and gravitational effects are important, Preskill wrote on his website in 2004.

Preskill thought that information isn't totally destroyed after being sucked into a black hole. One could theoretically find a way to reconstruct the aforementioned baseball encyclopedia, or pieces of it, from Hawking radiation.

Hawking and another physicist, Caltech's Kip Thorne, bet Preskill in 1997 that he was wrong about the information paradox and agreed to supply an encyclopedia to the winner.

Preskill won -- not because he discovered anything new, but because Hawking himself revised his calculations. In a 2004 talk and 2005 paper in the journal Physical Review D, Hawking reversed himself, saying that information could actually survive after entering a black hole, albeit in a mangled form. The reversal preserved the tenets of quantum mechanics but killed off the possibility of other universes branching off from black holes, according to the New York Times.

I'm sorry to disappoint science fiction fans, but if information is preserved, there is no possibility of using black holes to travel to other universes,'' Hawking said in 2004, according to the New York Times.

This isn't the first time Preskill has prevailed against Hawking -- the Cambridge professor conceded another bet that he made with his Caltech colleague in 1991. This bet, in which Thorne again joined, but on Preskill's side this time, concerned whether or not an object called a naked singularity could ever exist.

A singularity is a point where most of the things we know about the universe go haywire -- matter is infinitely dense, space-time is warped, and the strength of gravity shoots toward infinity. Singularities are predicted to lie in the hearts of black holes, behind an event horizon that masks them from observation. A naked singularity would have no event horizon, therefore, one could theoretically watch an object get crushed into something infinitely dense.

Though no one has actually observed a naked singularity, Preskill argued that one has been staring us in the face all along: the Big Bang.

Hawking admitted defeat in 1997 thanks to work from Matthew Choptuik, currently a professor at the University of British Columbia in Canada. Choptuik, then attached to the University of Texas in Austin, calculated that naked singularities were very improbable but could be created when a black hole is collapsed either naturally or artificially.

In a 1997 interview with the New York Times, Choptuik compared the likelihood of naked singularities arising to the chance that you could stand a sharpened pencil on its tip. But technically, Preskill and Thorne had won this one, so Hawking presented them with $100 each and T-shirts printed with the slogan Nature Abhors A Singularity.

One of the earliest high-profile physics wagers that Hawking made was with Thorne, over whether or not a space object called Cygnus X-1 was a black hole. Cygnus X-1, which lies near the center of the swan-shaped constellation Cygnus, was discovered in 1964 and spews massive amounts of X-rays into space.

Cygnus X-1 is nearly 15 times more massive than our sun, and most measurements have found that it isn't big enough to be a star or other space object, so it has been the most promising candidate for a black hole that scientists have ever seen. The X-rays emanating from Cygnus X-1 are most likely the remnants of gases from a star being boiled to temperatures beyond comprehension as it is sucked toward the singularity.

Hawking bet Thorne that Cygnus X-1 wasn't a black hole -- but, in this case, not because he was convinced he was right.

This was a form of insurance policy for me, he explained in A Brief History of Time.

Since Hawking had spent most of his life's work on black holes, if it turned out they didn't exist, he would have been able to console himself with a four-year subscription to Private Eye, a satirical English magazine.

By 1990, years of work by other scientists made a very strong case that Cygnus X-1 was a black hole, so Hawking did the gentlemanly thing: He broke into Thorne's office, signed the original paper detailing the bet and sent the winner a year of Penthouse magazine -- to the outrage of Kip's liberated wife, he later recalled.