Neutron stars in the context of $f$($\mathbb{T}$,$\mathcal{T}$) gravity

TL;DR

This paper explores neutron stars within $f$($ ext{T}$,$ ext{T}$) gravity, revealing significant effects on mass-radius profiles and matching observational data for specific parameter choices.

Contribution

It introduces hydrostatic equilibrium equations in $f$($ ext{T}$,$ ext{T}$) gravity and demonstrates their impact on neutron star properties using modern equations of state.

Findings

Mass-radius profiles are significantly affected by small parameter changes.

Results align with observed neutron star data such as LMXB NGC 6397 and PSR J0740+6620.

Certain parameter values can explain radii from PREX-2 experiment.

Abstract

In this work, we investigate the existence of neutron stars (NS) in the framework of $f$($\mathbb{T}$,$\mathcal{T}$) gravity, where $\mathbb{T}$ is the torsion tensor and $\mathcal{T}$ is the trace of the energy-momentum tensor. The hydrostatic equilibrium equations are obtained, however, with $p$ and $\rho$ quantities passed on by effective quantities $\bar{p}$ and $\bar{\rho}$, whose mass-radius diagrams are obtained using modern equations of state (EoS) of nuclear matter derived from relativistic mean field models and compared with the ones computed by the Tolman-Oppenheimer-Volkoff (TOV) equations. Substantial changes in the mass-radius profiles of NS are obtained even for small changes in the free parameter of this modified theory. The results indicate that the use of $f$($\mathbb{T}$,$\mathcal{T}$) gravity in the study of NS provides good results for the masses and radii of some important astrophysical objects, as for example, the low-mass X-ray binary (LMXB) NGC 6397 and the pulsar of millisecond PSR J0740+6620. In addition, radii results inferred from the Lead Radius EXperiment (PREX-2) can also be described for certain parameter values.