论文标题
婴儿宇宙，全息图和Swampland
Baby Universes, Holography, and the Swampland
论文作者
论文摘要
在许多沼泽条件下，我们认为，在量子重力的一致理论中，婴儿宇宙状态的希尔伯特空间必须是一维的。这种情况可以解释为量子重力中的一种“高斯定律”，并提供了欧几里得虫洞之间的张力和对全息词典的标准解释，不需要合奏。我们的观点至关重要地依赖于最近提供的具有不同拓扑结构的宇宙状态之间量子力学规格冗余的潜力。通过对国家经营者的通信的应用，该提案排除了紧凑型区域中支持的非平凡，严格定义的散装运营商的可能性。我们进一步评论了此假设中$ d \ leq 3 $中可能的例外，以及在低维度中全息理论的合奏的作用，例如$ d = 2 $的JT Gravity，以及$ d = 3 $的表亲。我们认为，这些例子是不完整的物理理论，应被视为较高的量子重力理论中的麸皮，合奏没有作用。
On the basis of a number of Swampland conditions, we argue that the Hilbert space of baby universe states must be one-dimensional in a consistent theory of quantum gravity. This scenario may be interpreted as a type of "Gauss's law for entropy" in quantum gravity, and provides a clean synthesis of the tension between Euclidean wormholes and a standard interpretation of the holographic dictionary, with no need for an ensemble. Our perspective relies crucially on the recently-proposed potential for quantum-mechanical gauge redundancies between states of the universe with different topologies. By an application of the state-operator correspondence, this proposal rules out the possibility of nontrivial, strictly well-defined bulk operators supported in a compact region. We further comment on the possible exceptions in $d\leq 3$ for this hypothesis, and the role of an ensemble for holographic theories in low dimensions, such as JT gravity in $d = 2$ and possible cousins in $d=3$. We argue that these examples are incomplete physical theories that should be viewed as branes in a higher dimensional theory of quantum gravity, for which an ensemble plays no role.
