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arXiv · 2406.06091

Cosmological coupling of local gravitational systems

Mariano Cadoni·Mirko Pitzalis·Davi C. Rodrigues·Andrea P. Sanna
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Abstract

We investigate the cosmological coupling of spherical, local astrophysical systems. We derive a general formula quantifying the cosmological coupling of the Misner-Sharp mass of these objects. We show that, in the weak-field limit, the cosmological coupling is only allowed if there are pressure anisotropies. We also apply our results to galaxies, modelling them with the Navarro-Frenk-White and Einasto profiles. We show that the galactic mass can be coupled to the cosmological dynamics and examine its dependence on the scale factor of the universe.

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Mariano Cadoni, Mirko Pitzalis, Davi C. Rodrigues, Andrea P. Sanna. 2024-06-10. Cosmological coupling of local gravitational systems. https://arxiv.org/abs/2406.06091

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