Magnetized Anisotropic Dark Energy Cosmological Model in f(T) Gravity with a Special Law of the Hubble Parameter
Abstract
In this paper, we investigate a magnetized anisotropic dark energy cosmological model in the framework of f(T) gravity for a locally rotationally symmetric Bianchi type-I spacetime. Choosing f(T)=0 reduces the theory to teleparallel gravity, dynamically equivalent to general relativity, enabling direct comparison with standard cosmology. Exact solutions of the field equations are obtained by assuming a special law of the Hubble parameter with a nonzero constant S, yielding power-law behavior of the directional scale factors.
A uniform magnetic field aligned along one spatial direction produces an early-time anisotropy whose energy density decays with cosmic expansion. The energy density, pressure, the equation-of-state parameter, and the energy conditions are analyzed. The pressure remains negative, while the equation-of-state parameter evolves dynamically and approaches the range -1 ≤ ω < -1/3 at late times, consistent with SN Ia and CMB constraints. The null and weak energy conditions are violated at late times, whereas the strong energy
condition is violated throughout, implying acceleration.
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