标题： 熵原理 显示英文标题

标题： Entropic Principles

摘要： 我们讨论在膨胀的各向同性宇宙中辐射和贝肯斯坦-霍金熵的演化。 我们建立了一个普遍的关系，说明为什么目前这两种熵的数值存在巨大的差异是不可避免的。 给出了它们数值的一些人择约束，并讨论了宇宙学“熵差”问题的其他方面。 当黑洞的霍金寿命等于宇宙的年龄，因此半径等于质子尺寸时，经典熵和量子熵的巧合被证明与我们在主序星寿命阶段观测宇宙的条件相同。 显示英文摘要

摘要： We discuss the evolution of radiation and Bekenstein-Hawking entropies in expanding isotropic universes. We establish a general relation which shows why it is inevitable that there is currently a huge difference in the numerical values of these two entropies. Some anthropic constraints on their values are given and other aspects of the cosmological 'entropy gap' problem are discussed. The coincidence of the classical and quantum entropies for black holes with Hawking lifetime equal to the age of the universe, and hence of radius equal to the proton size, is shown to be identical to the condition that we observe the universe at the main-sequence lifetime.