We present modified cosmological scenarios that arise from the application of the "gravity-thermodynamics" conjecture, using the Barrow entropy instead of the usual Bekenstein-Hawking one. The former is a modification of the black hole entropy due to quantum-gravitational effects that deform the black-hole horizon by giving it an intricate, fractal structure. We extract modified cosmological equations which contain new extra terms that constitute an effective dark-energy sector, and which coincide with the usual Friedmann equations in the case where the new Barrow exponent acquires its Bekenstein-Hawking value. We present analytical expressions for the evolution of the effective dark energy density parameter, and we show that the universe undergoes through the usual matter and dark-energy epochs. Additionally, the dark-energy equation-of-state parameter is affected by the value of the Barrow deformation exponent and it can lie in the quintessence or phantom regime, or experience the phantom-divide crossing. Finally, at asymptotically large times the universe always results in the de-Sitter solution.

中文翻译：

---

通过时空热力学和巴罗视界熵修正宇宙学

我们使用 Barrow 熵而不是通常的 Bekenstein-Hawking 熵，展示了应用“重力-热力学”猜想而产生的修改后的宇宙学情景。前者是由于量子引力效应对黑洞熵的修改，通过赋予其复杂的分形结构使黑洞视界变形。我们提取修改后的宇宙学方程，其中包含构成有效暗能量扇区的新额外项，并且在新巴罗指数获得其 Bekenstein-Hawking 值的情况下，与通常的弗里德曼方程相吻合。我们提出了有效暗能量密度参数演化的解析表达式，并表明宇宙经历了通常的物质和暗能量时代。此外，暗能量状态方程参数受 Barrow 变形指数值的影响，它可以位于精华或幻影区域，或经历幻影分割交叉。最后，在渐近大的时间内，宇宙总是会产生去西特解。