[source: Sudan-T]
Report: Astrophysicist Stephen Hawking loses bet
NEW YORK - Stephen W. Hawking - the Cambridge University theorist
regarded by some as one of Albert Einstein's
intellectual successors - has conceded defeat in a famous six-year-old
bet.
Hawking bet two professors at the California Institute of Technology
that naked singularities - variations on a cosmological phenomenon
believed to lurk at the hearts of black holes - could not exist.
Now it seems they could - maybe.
The New York Times reports Wednesday that during a visit to Cal Tech
last week, Hawking conceded defeat "on a
technicality" to fellow physicists John P. Preskill and Kip S. Thorne.
The stake was 100 pounds (about $164), plus clothing "embroidered with a
suitable concessionary message."
Hawking, Preskill and Thorne are leaders in the study of relativity as
applied to cosmology, and they meet often at scientific symposiums,
discussing conjectures about time machines, wormholes, the origin of the
universe and other questions.
Although he was unable to prove his disbelief in naked singularities,
Hawking, the author of A Brief History of Time, proposed his bet at one
such meeting in 1991. Because of its far-reaching theoretical
implications, news of the bet spread widely among physicists.
For the uninitiated, a singularity is a mathematical point at which
space and time are infinitely distorted, where matter is infinitely
dense, and where the rules of relativistic physics and quantum mechanics
break down.
Singularities are believed to lurk at the center of black holes, which
conceal their existence from the outer world. A naked singularity would
be a singularity bereft of a concealing black-hole shell, and therefore
visible, in principle, to outside observers.
Although neither light nor any other kind of signal can escape from
them, a half-dozen or so black holes have been revealed by their
gravitational effects of nearby stars. Black holes also have betrayed
their presence by sucking matter from nearby space. As the matter
spirals toward the hole, it is heated to incandescence, and the emission
of X-rays and other radiation has been detected by observatories in
space and on the ground.
Preskill and Thorne won the bet last week on the strength of
supercomputer calculations by Matthew Choptuik of the University of
Texas in Austin. Choptuik concluded from his mathematical analysis that
there could be special circumstances in which a naked singularity might
be created from a collapsing black hole, either by nature or perhaps
even by some advanced civilization.
The chance of this happening, Choptuik told the Times, would be
comparable to standing a pencil upright on its sharpened tip -
improbable, yet theoretically possible.
Hawking declined to yield unequivocally - he made another bet with the
Cal Tech physicists that although a very limited set of conditions had
been found for creating naked singularities, no general conditions would
be found.
And the concessionary message Hawking had printed on T-shirts hardly
conceded defeat. The shirts read: "Nature Abhors a Naked Singularity."
"All this has a very serious undertone," Preskill told the Times. "If we
are ever to understand singularities we must do so in terms of some
yet-to-be-discovered theory of quantum gravity, and that would be a
revolution in physics. We're not there yet."
By The Associated Press
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