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arXiv · 2508.16562

Energy-momentum response to metric perturbations in the fluid dynamic regime

Tim Stoetzel·Rebekka Fechtner·Stefan Floerchinger
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Abstract

The interplay of relativistic fluid dynamics and spacetime geometry is discussed in the regime of small wave numbers and frequencies. A combination of gravitational Ward identities and fluid dynamic equations of motion in the Mueller-Israel-Stewart formulation is used to explicitly determine the retarded linear response of the energy-momentum tensor to metric perturbations. We also discuss applications to gravitational wave production and the damping of gravitational waves in a relativistic fluid.

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Tim Stoetzel, Rebekka Fechtner, Stefan Floerchinger. 2025-08-22. Energy-momentum response to metric perturbations in the fluid dynamic regime. https://arxiv.org/abs/2508.16562

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