In the framework of entropic cosmology, several scenarios of the evolution of the Friedman-Robertson-Walker (FRW) Universe are considered, based on a new modification of the non-additive Sharma-Mittal and Renyi entropy measures on the cosmological horizon. This is done by replacing in the original logarithmic formulas for these entropies, the Tsallis entropy by the Barrow entropy associated with the modification of the horizon surface due to quantum gravitational effects. Several versions of the generalised multi-parametric FRW equations have been constructed, which can serve as an effective theoretical basis for describing the accelerating phase of the expansion of the late Universe. In the considered model there is no mutual interaction between the black components of the cosmos. The proposed approach, based on the use of non-additive extensive entropic measures on the cosmological horizon, meets the well-known requirements for thermodynamic modelling of the dynamical evolution of the Universe without involving the concept of hypothetical dark energy, but using the antigravity effect of entropic forces. The obtained results show that the generalised entropic formalism can open new possibilities for a deeper insight into the nature of spacetime and its fractal properties.
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