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arXiv · 2004.08214

Accelerating bianchi type dark energy cosmological model with cosmic string in f(T) Gravity

S. H. Shekh·V. R. Chirde
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Abstract

In this paper, we have investigated some features of anisotropic accelerating Bianchi type-I cosmological model in the presence of two non-interacting fluids, i.e. one usual string and other dark energy fluid towards the gravitational field equations for the linear form of $f(T)$ gravity, where \textit{T }be the torsion. To achieve a physically realistic solution of the field equations, we have considered an exact matter dominated volumetric power law expansion. The aspects of derived model are discussed with the help of solution and make the model at late times turn out to be flat Universe. Also, observed that the model has initially non-singular and stable while for whole expansion it is unstable. At an initial expansion $0.01\le t\le 0.05$ when the Universe start to expand to infinite expansion $t>1.73$ (break away from for small interval of cosmic time $0.06\le t\le 1.73$), there is a matter dominated era while for $0.06\le t\le 1.73$ it approaches the quintessence region. Also, the string exists in the early universe which is in agreement with constraints of CMBR data but with the expansion the string phase of the Universe disappears, i.e. we have an anisotropic fluid of particles.

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S. H. Shekh, V. R. Chirde. 2020-03-26. Accelerating bianchi type dark energy cosmological model with cosmic string in f(T) Gravity. https://doi.org/10.1007/s10509-020-03772-y

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