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arXiv · 2112.01264

Thermodynamics of galaxy clusters in modified Newtonian potential

Abdul W. Khanday·Sudhaker Upadhyay·Prince A. Ganai
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Abstract

We study the thermodynamics of galaxy clusters in a modified Newtonian potential motivated by a general solution to Newton's "sphere-point" equivalence theorem. We obtain the $N$ particle partition function by evaluating the configurational integral while accounting for the extended nature of galaxies (via the inclusion of the softening parameter $ε$ into the potential energy function). This softening parameter takes care of the galaxy-halos whose effect on structuring the shape of the galactic disc has been found recently. The spatial distribution of the particles (galaxies) is also studied in this framework. A comparison of the new clustering parameter $b_+$ to the original clustering parameters is presented in order to visualize the effect of the modified gravity. We also discuss the possibility of system symmetry breaking via the behavior of the specific heat as a function of temperature.

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Abdul W. Khanday, Sudhaker Upadhyay, Prince A. Ganai. 2021-12-15. Thermodynamics of galaxy clusters in modified Newtonian potential. https://doi.org/10.1088/1402-4896%2Fac3a4a

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