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arXiv · 2608.04988

The Roche-Lobe Radius in Newtonian and Non-Newtonian Gravity

A. M. Velasquez-Toribio
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Abstract

In this paper, we extend the standard calculation of the Roche lobe from the Newtonian potential to non-Newtonian models, specifically Yukawa-type and power-law potentials. These models are significant because they arise from unification theories, such as those involving extra dimensions or scalar-tensor gravity. Furthermore, we develop fitting formulas for the equivalent volume radius R_L under these potentials, analogous to $Eggleton s$ formula for the Newtonian case. We calibrate the fitting formulas of the non-Newtonian potentials with their corresponding numerical solutions.

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A. M. Velasquez-Toribio. 2026-08-05. The Roche-Lobe Radius in Newtonian and Non-Newtonian Gravity. https://doi.org/10.1007/s10509-026-04611-2

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