Renato Renner | June 20, 2022 | A quantum information perspective on black holes
Speaker: Renato Renner, ETH Zurich
Title: A quantum information perspective on black holes
Abstract: Recent calculations based on gravitational path integrals provide strong support for the hypothesis that the entropy of Hawking radiation follows the Page curve, indicating that the underlying time evolution is unitary (and thus in principle reversible). In this talk I will revisit these calculations from a quantum information-theoretic perspective. Specifically, I will show that the quantum de Finetti theorem can provide insights on the precise nature of the entropy measure that is actually computed by gravitational path integrals. One of the conclusions is that this entropy is best understood as the regularised joint entropy of the radiation emitted by a collection of many identical black holes, rather than the entropy of the radiation emitted by a single black hole. There is evidence that the latter is strictly larger than the former. This would imply that the Hawking radiation emitted by multiple black holes is correlated, even if they were prepared independently.