A New Proof of the QNEC
Abstract We give a simplified proof of the quantum null energy condition (QNEC). Our proof is based on an explicit formula for the shape derivative of the relative entropy, with respect to an entangling cut. It allows bypassing the analytic continuation arguments of a previous proof by Ceyhan and Faulkner and can be used e.g., for defining entropy current fluctuations.
Authors
- Stefan Hollands (ORCID: https://orcid.org/0000-0001-6627-2808)
- Roberto Longo (ORCID: https://orcid.org/0000-0001-7923-3226)
Institutions
- University of Rome Tor Vergata (IT)
- Max Planck Institute for Mathematics in the Sciences (DE)
- Max Planck Institute for Mathematics (DE)
- Leipzig University (DE)
Publication Details
- Journal
- Communications in Mathematical Physics
- Published
- 2025-10-03
- DOI
- https://doi.org/10.1007/s00220-025-05450-y
- Citations
- 3
- Primary Topic
- Black Holes and Theoretical Physics
- Type
- article
- Field-Weighted Citation Impact
- 5.61
Funders
- Ministero dell’Istruzione, dell’Università e della Ricerca
- Università degli Studi di Roma Tor Vergata