Bak, Sang EonSang EonBakParikh, MaulikMaulikParikhSarkar, SudiptaSudiptaSarkarSetti, FrancescoFrancescoSetti2025-08-312025-08-312024-07-0110.1007/JHEP07(2024)2142-s2.0-85199343154http://repository.iitgn.ac.in/handle/IITG2025/28847We 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.trueClassical Theories of Gravity | Models of Quantum GravityArticlehttps://doi.org/10.1007/jhep07(2024)21410298479July 20242214arJournal2WOS:001274896600002