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arXiv · 2506.17192

Gravitational lensing observables in stationary and axisymmetric solutions in general relativity

Matteo Luca Ruggiero·Davide Astesiano
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Abstract

We investigate light propagation in self-gravitating systems composed of an axially symmetric, stationary, rotating dust fluid. These configurations are intrinsically relativistic, sustained entirely by their rotation, since no compact or finite dust distribution can exist under the same symmetry conditions in Newtonian gravity. In such systems, rotational effects arise from off-diagonal components of the spacetime metric, which are not negligible compared to their Newtonian counterparts. We analyze how these components affect the deflection angle of light, showing that they can be interpreted as contributing an additional effective mass. Moreover, their presence can, in principle, be detected through the characteristic asymmetry they induce in the images of background sources.

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Matteo Luca Ruggiero, Davide Astesiano. 2025-06-20. Gravitational lensing observables in stationary and axisymmetric solutions in general relativity. https://doi.org/10.1103/nbl9-6hnc

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