Cosmic Expansion Driven by Barrow Entropy

Abstract

The concept of cosmic acceleration has become one of the fundamental concerns of modern cosmology. While the standard ΛCDM model incorporates dark energy to explain the accelerated expansion of the universe, alternative approaches are explored to understand cosmic dynamics. One such approach is Barrow entropic cosmology, which provides a generalized framework for cosmological thermodynamics by considering fractal deviations in the entropy-area relationship. In this sense, this study investigates the effects of Barrow's entropy on cosmological dynamics for the accelerating universe, focusing on modifications to the Friedmann equations. The results are compared with supernovae and CMB data based on the standard ΛCDM model, and provide insights into the applicability of Barrow cosmology as an alternative to dark energy. It is shown that the introduced Barrow correction term can explain the expanding universe. For Barrow parameter, which values are limited to the range 0≤∆ ≤1, as Δ increases, H(z) values approach the standard at low redshifts (z<0.5) but show significant deviations at high redshifts (z>1).

Keywords

• Barrow entropy
• entropic acceleration
• expanding universe

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