近日，美国科罗拉多大学Higginbotham, Kenneth团队进行了关于AdS/CFT婴儿宇宙的测试。该项研究成果发表在2025年9月3日出版的《高能物理杂志》上。

为了解决Antonini和Rath提出的一个谜题——一个CFT状态有两个双星，一个有婴儿宇宙，另一个没有——Engelhardt和Gesteau最近设计了一个测试AdS/CFT中的婴儿宇宙。利用外推数据库，他们证明了体积交换测试的边界对偶倾向于没有婴儿宇宙的体积时空，这为它们的半经典有效性提供了证据。

然而，最近的研究表明，全息地图应该在这样封闭的宇宙上进行后选择，研究组认为这与外推数据库是一致的。因此，他们构建了一个新的具有婴儿宇宙的体态全息图，并以此为主题来表明交换测试不能区分Antonini和Rath的两个候选体双子星。这不仅允许对婴儿宇宙进行有效的半经典描述，而且还允许将观察者包括在全息地图中的最新技术的应用。

附：英文原文

Title: On tests for baby universes in AdS/CFT

Author: Higginbotham, Kenneth

Issue&Volume: 2025-09-03

Abstract: To address a puzzle by Antonini and Rath — where a single CFT state has two bulk duals, one with a baby universe and one without — Engelhardt and Gesteau recently devised a test for baby universes in AdS/CFT. Using the extrapolate dictionary, they showed that the boundary dual of a bulk swap test favored bulk spacetimes without a baby universe, providing evidence against their semiclassical validity. However, recent work suggests that holographic maps should post-select on such closed universes, and we argue that this is consistent with the extrapolate dictionary. We therefore construct a new holographic map for bulk states with baby universes and use this to show that the swap test cannot distinguish between Antonini and Rath’s two candidate bulk duals. This not only allows for a valid semiclassical description of the baby universe, but also enables the application of recent techniques for including observers in holographic maps.

DOI: 10.1007/JHEP09(2025)038

Source: https://link.springer.com/article/10.1007/JHEP09(2025)038