HAWKING ATTRIBUTES LOST WAGER TO `TECHNICALITY' ON COSMIC SCALE.

Byline: Malcolm W. Browne The New York Times

Dr. Stephen Hawking of Cambridge University in England - the brilliant theorist regarded as one of Albert Einstein's intellectual successors - has conceded defeat in a famous bet he made six years ago on a matter of cosmic significance.

The bet he made with two professors at the California Institute of Technology, in Pasadena, was that naked singularities could not exist, and now, it seems, they could - maybe.

During a visit to Caltech last week, Hawking, the author of ``A Brief History of Time,'' a book that delves into the origins of the universe, conceded defeat ``on a technicality'' to Dr. John Preskill and Dr. Kip Thorne. The stake was for 100 pounds, plus clothing ``embroidered with a suitable concessionary message.''

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 hearts 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 on nearby stars. Black holes also have betrayed their presence by sucking in matter from nearby space. As it spirals toward the hole, the matter is heated to incandescence and the emission of X-rays and other radiation has been detected by observatories in space and on the ground.

Hawking, Preskill and Thorne are leaders in the study of relativity as applied to cosmology, and they meet often at scientific symposiums. Subjects they take up often include conjectures about time machines, relativistic tunnels called wormholes to distant points in space and time, the origin of the universe, and many other intriguing questions.

It was at such a meeting in 1991 that Hawking, although he was unable to prove his disbelief in naked singularities, proposed his bet to Preskill and Thorne. Because of its far-reaching theoretical implications, news of their bet spread among physicists throughout the world.

Preskill and Thorne won the bet last week on the strength of supercomputer calculations by Dr. 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 said in an interview, would be comparable to standing a pencil upright on its sharpened tip. Although it is improbable, it is theoretically possible.

Hawking, who is paralyzed but speaks electronically by tapping out words on a telegraph key, said that even in light of the new calculations, there is no ``generic'' way in which naked singularities might form according to the known laws of physics.

But Preskill replied: ``Stephen, I'm surprised to hear you, of all people, say that. There's one naked singularity that we all agree existed: the Big Bang. The universe itself.''

Hawking declined to yield unequivocally on his bet with Preskill and Thorne. He made another bet with the Caltech physicists last week that although a very limited set of conditions had been found for creating naked singularities, no general conditions would be found.

And what was supposed to be the concessionary message from the bet that Hawking had printed on the T-shirts was hardly an admission of defeat: ``Nature Abhors a Naked Singularity.''