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arXiv · 2012.03342

Radial oscillations and stability of compact stars in $f(R, T) = R+ 2\beta T$ gravity

Juan M. Z. Pretel·Sergio E. Jorás·Ribamar R. R. Reis·José D. V. Arbañil
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Abstract

We examine the static structure configurations and radial stability of compact stars within the context of $f(R, T)$ gravity, with $R$ and $T$ standing for the Ricci scalar and trace of the energy-momentum tensor, respectively. Considering the $f(R, T)=R+2\beta T$ functional form, with $\beta$ being a constant, we derive the corresponding hydrostatic equilibrium equation and the modified Chandrasekhar's pulsation equation. The mass-radius relations and radial mode frequencies are obtained for some realistic equations of state. Our results show that the traditional stellar stability criteria, namely, the necessary condition $dM/d\rho_c >0$ and sufficient condition $\omega^2 >0$, still hold in this theory of gravity.

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Juan M. Z. Pretel, Sergio E. Jorás, Ribamar R. R. Reis, José D. V. Arbañil. 2020-12-06. Radial oscillations and stability of compact stars in $f(R, T) = R+ 2\beta T$ gravity. https://doi.org/10.1088/1475-7516/2021/04/064

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