aiqbench analysis
This paper addresses the information loss paradox within canonical quantum gravity by proposing a framework where black hole evaporation occurs without an event horizon, utilizing coherent states in gravitational phase space. The authors demonstrate that this approach reconciles semi-classical dynamics with unitary time evolution at a fine-grained level, though it necessitates violating standard entropy bounds. This theoretical development is significant for researchers investigating the fundamental intersection of quantum mechanics and general relativity.
Unitary evolution of an evaporating black hole in canonical quantum gravity
arXiv:2609.13375v1 Announce Type: cross Abstract: We propose a framework for understanding the information loss paradox in the context of canonical quantum gravity. We first revisit several approaches to black hole evaporation that do not involve an event horizon. In these models, we assume that each time slice corresponds to a coherent state in the gravitational phase space. Due to this property, the quantum state associated with a given spatial configuration will have a nonzero overlap with another spatial configuration. We show how this property can account for both semi-classical dynamics and unitary time evolution. We introduce an explicit toy model that follows semi-classical time evolution at the coarse-grained level; in addition, its time evolution is unitary at the fine-grained level. The only price that one must pay is the violation of the entropy bound; we discuss reasons why this may be justifiable.
Abstract:We propose a framework for understanding the information loss paradox in the context of canonical quantum gravity. We first revisit several approaches to black hole evaporation that do not involve an event horizon. In these models, we assume that each time slice corresponds to a coherent state in the gravitational phase space. Due to this property, the quantum state associated with a given spatial configuration will have a nonzero overlap with another spatial configuration. We show how this property can account for both semi-classical dynamics and unitary time evolution. We introduce an explicit toy model that follows semi-classical time evolution at the coarse-grained level; in addition, its time evolution is unitary at the fine-grained level. The only price that one must pay is the violation of the entropy bound; we discuss reasons why this may be justifiable.
arXiv:2609.13375 [gr-qc]
(or arXiv:2609.13375v1 [gr-qc] for this version)
https://doi.org/10.48550/arXiv.2609.13375 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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Full text under the publisher's open licence · 228 words
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