Black hole entropy, the black hole information paradox, and time travel paradoxes from a new perspective

TL;DR

This paper offers new perspectives on black hole entropy, the information paradox, and time travel paradoxes, suggesting that quantum physics and the Everett interpretation resolve these issues through a unified framework.

Contribution

It introduces novel viewpoints connecting black hole thermodynamics, quantum measurement, and time travel paradoxes within a quantum path integral approach.

Findings

Black hole entropy explained via Euclidean path integrals and microstates.

Quantum unitarity preserved through Everett interpretation during Hawking radiation detection.

Time travel paradoxes are resolved by quantum field descriptions on nontrivial manifolds.

Abstract

Relatively simple but apparently novel ways are proposed for viewing three related subjects: black hole entropy, the black hole information paradox, and time travel paradoxes. (1) Gibbons and Hawking have completely explained the origin of the entropy of all black holes, including physical black holes -- nonextremal and in 3-dimensional space -- if one can identify their Euclidean path integral with a true thermodynamic partition function (ultimately based on microstates). An example is provided of a theory containing this feature. (2) There is unitary quantum evolution with no loss of information if the detection of Hawking radiation is regarded as a measurement process within the Everett interpretation of quantum mechanics. (3) The paradoxes of time travel evaporate when exposed to the light of quantum physics (again within the Everett interpretation), with quantum fields properly described by a path integral over a topologically nontrivial but smooth manifold.