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arXiv · 2408.16497

Application of Kaluza-Klein Theory in Modeling Compact Stars: Exploring Extra Dimensions

Anna Horváth·Emese Forgács-Dajka·Gergely Gábor Barnaföldi
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Abstract

A theoretical framework for calculating the mass-radius curve of compact stars in the Kaluza-Klein space-time is introduced, with one additional compact spatial dimension. Static, spherically symmetric solutions are considered, with the equation of state provided by a zero temperature, interacting multidimensional Fermi gas. To model the strong force between baryons, a repulsive potential is introduced, which is linear in the particle number density. The maximal mass of compact stars is calculated for different model parameters, and with a physical parameter choice, it satisfies observational data, meaning that it is possible to model simple, realistic objects within this framework. Based on this comparison, a limiting size for the observational regime of extra dimensions in compact stars is provided, with $r_c \gtrsim 0.2$~fm.

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Anna Horváth, Emese Forgács-Dajka, Gergely Gábor Barnaföldi. 2024-08-29. Application of Kaluza-Klein Theory in Modeling Compact Stars: Exploring Extra Dimensions. https://doi.org/10.1093/mnras%2Fstae2637

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