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arXiv · 2402.00081

Comment on "The Tully-Fisher law and dark matter effects derived via modified symmetries" by Arraut Ivan

L. Filipe O. Costa·F. Frutos-Alfaro·José Natário·Michael Soffel
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Abstract

It has been claimed in I. Arraut, 2023 EPL 144 29003 [arXiv:2311.05652] that General Relativity can generate effects equivalent to dark matter, based on a "new modified symmetry that emerges at galactic scale". We show that (i) the spacetime considered is unphysical, violating energy conditions everywhere; (ii) actually no new symmetry emerges, which results from incorrect definitions of angular momentum, velocity, and arclength in the proposed geometry; (iii) no Tully-Fisher law, or flat rotation curves are obtained either, they simply result from a series of errors in the equations.

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L. Filipe O. Costa, F. Frutos-Alfaro, José Natário, Michael Soffel. 2024-01-31. Comment on "The Tully-Fisher law and dark matter effects derived via modified symmetries" by Arraut Ivan. https://doi.org/10.1209/0295-5075%2Fad2728

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