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arXiv · 2312.17214

Quantum-Gravitational Null Raychaudhuri Equation

Sang-Eon Bak·Maulik Parikh·Sudipta Sarkar·Francesco Setti
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Abstract

We consider a congruence of null geodesics in the presence of a quantized spacetime metric. The coupling to a quantum metric induces fluctuations in the congruence; we calculate the change in the area of a pencil of geodesics induced by such fluctuations. For the gravitational field in its vacuum state, we find that quantum gravity contributes a correction to the null Raychaudhuri equation which is of the same sign as the classical terms. We thus derive a quantum-gravitational focusing theorem valid for linearized quantum gravity.

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Sang-Eon Bak, Maulik Parikh, Sudipta Sarkar, Francesco Setti. 2023-12-28. Quantum-Gravitational Null Raychaudhuri Equation. https://doi.org/10.1007/jhep07(2024)214

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