标题： 全息熵界限和宇宙学中一类特殊的空间系统 显示英文标题

标题： Holographic entropy bound and a special class of spatial systems in cosmology

摘要： 全息熵界限在宇宙学中被讨论。 我们尝试在宇宙学中定义一类特殊的时空系统，在其中物质的熵在整个宇宙演化过程中都满足全息熵界限。 我们首先以由黑洞组成的宇宙为例，并证明此类特殊系统确实存在。 然后，从共动体积内的熵的角度来看，我们发现对于此类特殊时空系统存在一个普遍的定义，即该定义独立于宇宙的组分。 最后，我们证明在某些特定的宇宙学模型中，可以对此类特殊时空系统提出多种定义，并分析这些多种定义出现的潜在原因。 显示英文摘要

摘要： The holographic entropy bound is discussed in cosmology. We try to define a special class of spatial systems in cosmology, inside which the entropy of matter satisfies the holographic entropy bound throughout the evolution of the universe. We first take a universe composed of black holes as an example and demonstrate that such a special class of systems does exist. Then, from the perspective of entropy inside the co-moving volume, we find that there exists a universal definition for this special class of spatial systems, i.e., the definition is independent of the components of the universe. Finally, we prove that in some specific cosmological models, multiple definitions can arise for this special class of spatial systems, and we analyze the underlying reasons for the emergence of these multiple definitions.