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arXiv · 2207.08570

Anisotropic spacetimes in $f(T,B)$ theory II: Kantowski-Sachs Universe

Genly Leon·Andronikos Paliathanasis
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Abstract

In the context of the modified teleparallel $f(T, B)$-theory of gravity, we consider a homogeneous and anisotropic background geometry described by the Kantowski-Sachs line element. We derive the field equations and investigate the existence of exact solutions. Furthermore, the evolution of the trajectories for the field equations is studied by deriving the stationary points at the finite and infinite regimes. For the $f(T,B)=T+F\left( B\right) $ theory, we prove that for a specific limit of the function $F\left( B\right) $, the anisotropic Universe has the expanding and isotropic Universe as an attractor with zero spatial curvature. We remark that there are no future attractors where the asymptotic solution describes a Universe with nonzero spatial curvature.

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Genly Leon, Andronikos Paliathanasis. 2022-07-18. Anisotropic spacetimes in $f(T,B)$ theory II: Kantowski-Sachs Universe. https://arxiv.org/abs/2207.08570

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