Pure three-dimensional gravity is a renormalizable theory with twofree parameters labelled by
We prove an equivalence between the classical equations of motion governing vacuum gravity compactifications (and more general warped-product spacetimes) and a concavity property of entropy under time evolution. This is obtained by linking the theory of optimal transport to the Raychaudhuri equation in the internal space, where the warp factor introduces effective notions of curvature and (negative) internal dimension. When the Reduced Energy Condition is satisfied, concavity can be characterized in terms of the cosmological constant
- Award ID(s):
- 2014215
- NSF-PAR ID:
- 10477565
- Publisher / Repository:
- SciPost
- Date Published:
- Journal Name:
- SciPost Physics
- Volume:
- 15
- Issue:
- 2
- ISSN:
- 2542-4653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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