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arXiv · 2609.37692

On more general Gibbons-Hawking-York boundary terms for f(R) gravity

Federico Scali·Sergio Luigi Cacciatori·Matteo Galaverni·Gabriele Gionti
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Abstract

More general boundary conditions are introduced - with respect to known literature - which produce a well-posed stationary action principle in $f(R)$ gravity. These conditions encompass the known cases, thus enlarging the space of admissible solutions. The corresponding Gibbons-Hawking-York boundary terms are explicitly computed and hold for any analytic f(R). The perspectives of application concerning the scalar-tensor mapping and the laws of black-hole thermodynamics are outlined in the conclusions.

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Federico Scali, Sergio Luigi Cacciatori, Matteo Galaverni, Gabriele Gionti. 2026-09-29. On more general Gibbons-Hawking-York boundary terms for f(R) gravity. https://arxiv.org/abs/2609.37692

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