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arXiv · 2405.01296

Cutoff Scale of Quadratic Gravity from Quantum Focusing Conjecture

Takamasa Kanai·Kengo Maeda·Toshifumi Noumi·Daisuke Yoshida
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Abstract

We derive the cutoff length scale of the quadratic gravity in $d \geq 5$ dimensional spacetime by demanding that the quantum focusing conjecture for the smeared quantum expansion holds at the classical level. The cutoff scale has different dependence on the spacetime dimension depending on the sign of the coupling constant of the quadratic gravity. We also investigate a concrete example of the 5-dimensional Schwarzschild spacetime and directly confirm that the quantum focusing conjecture holds when the quantum expansion is smeared over the scale larger than our cutoff scale.

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Takamasa Kanai, Kengo Maeda, Toshifumi Noumi, Daisuke Yoshida. 2024-05-02. Cutoff Scale of Quadratic Gravity from Quantum Focusing Conjecture. https://arxiv.org/abs/2405.01296

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