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arXiv · 2205.12229

Newtonian approximation in (1 + 1) dimensions

Roberto Casadio·Octavian Micu·Jonas Mureika
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Abstract

We study the possible existence of a Newtonian regime of gravity in $1+1$ dimensions, considering metrics in both the Kerr-Schild and conformal forms. In the former case, the metric gives the exact solution of the Poisson equation in flat space, but the weak-field limit of the solutions and the non-relativistic regime of geodesic motion are not trivial. We show that using harmonic coordinates, the metric is conformally flat and a weak-field expansion is straightforward. An analysis of the non-relativistic regime of geodesic motion remains non-trivial and the weak-field potential only satisfies the flat space Poisson equation approximately.

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Roberto Casadio, Octavian Micu, Jonas Mureika. 2022-05-26. Newtonian approximation in (1 + 1) dimensions. https://doi.org/10.1088/1402-4896%2Fac9e80

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