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arXiv · 2210.01574

Charged anisotropic white dwarfs in $f\left({R}, {T}\right)$ gravity

Zhe Feng
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Abstract

In the context of $f\left(R, T\right) = R + 2 \beta T$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, the equilibrium structure of charged anisotropic white dwarfs (WDs) is studied. The stellar equations for the general case are derived and numerical solutions are found for the Chandrasekhar equation of state (EoS) and a charge density distribution proportional to the energy density $\rho_{\text{ch}} = \alpha \rho$. By adjusting different parameters, the properties of the solutions under various conditions are compared. Most importantly, by going beyond the trivial WD in GR in various ways, the solutions may exhibit super-Chandrasekhar behavior. This article is a study of a WD structure, and the results obtained may have a contrasting effect on astronomical observations such as superluminous type Ia supernovae.

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Zhe Feng. 2022-09-30. Charged anisotropic white dwarfs in $f\left({R}, {T}\right)$ gravity. https://doi.org/10.1142/s0217732324502183

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