Théorie des cordes, entropie des trous noirs et radiation d’Hawking : de nouvelles réponses pour d’anciennes questions.
Curtis Callan (Université de Princeton, LPT-ENS)

Jeudi 4 juin 1998

In this talk I will describe recent advances in our understanding of the quantum physics of black holes. The problem of identifying the states counted by the Bekenstein-Hawking black hole entropy and the related problem of information loss via Hawking radiation have puzzled quantum theorists for many years. Recent developments in string theory have revolutionized our understanding of these questions.

An improved understanding of duality has taught string theorists how to build a wide variety of solitons whose masses and charges can be freely varied. Some of them appear, from the outside, virtually identical to well-known black hole solutions of general relativity.

The string theory analysis shows that these solitons possess an extremely degenerate set of internal states whose statistical entropy, as a function of the overall mass and charges, can be calculated. In a remarkably wide range of cases, the result agrees in quantitative detail with the appropriate Bekenstein-Hawking formula. The same reasoning applied to slightly non-extremal versions of these black holes leads to a remarkable mechanistic model of Hawking radiation itself which also agrees with the classic formulae.