Anisotropic stellar evolution and exotic matter

Abstract

In this paper, we discuss the stability of isotropic pressure
conditions for a spherically symmetric dissipative fluid
distribution in the framework of
$\mathfrak{f}(\mathcal{G},\mathrm{T})$ gravity. We consider the
fluid to be composed of seen and exotic matter particles. The Gauss
Bonnect terms represent exotic matter particles. For the physical
significance of the pressure isotropy conditions, we transform the
system into the hydrostatic equilibrium approximation. We observe
the presence of shear, dissipative fluxes, energy density
inhomogeneities, and prominently, the exotic matter tends to abandon
isotropy leading to pressure anisotropy. It is found that exotic
matter and dissipation are major factors that induce matter
anisotropy in the evolving stellar system. To strengthen the
results, we also incorporate some arguments by choosing an axially
symmetric case.