Bianchi Type–VII Cosmological Model with Tsallis–Barrow Holographic Dark Energy in Lyra Geometry
DOI:
https://doi.org/10.26565/2312-4334-2026-2-04Keywords:
Bianchi type–VII cosmology, Lyra geometry, Tsallis–Barrow holographic dark energy, Anisotropic Universe, Modified gravity, Cosmological diagnosticsAbstract
In this work, we investigate an anisotropic Bianchi type–VII cosmological model in the framework of Lyra geometry filled with perfect fluid matter and Tsallis–Barrow holographic dark energy. The modified Einstein field equations are derived, and exact solutions are obtained by assuming a power-law average scale factor for a decelerating universe. Expressions for various cosmological parameters such as the Hubble parameter, expansion scalar, shear scalar, matter density, dark energy density, and density parameters are derived and analysed. The behaviour of these parameters indicates that the universe is expanding continuously, with the expansion rate decreasing with cosmic time. The anisotropy parameter decreases gradually, indicating that the universe evolves towards isotropy at late times. Energy conditions, stability analysis, and cosmological diagnostics, including the statefinder and Om parameters, are also examined to evaluate the model's physical viability. The results suggest that Tsallis–Barrow entropy corrections in Lyra geometry provide a consistent framework for studying anisotropic cosmological evolution and dark energy dynamics.
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