标题： 磁性膜宇宙：宇宙学和虫洞 显示英文标题

标题： Magnetic Braneworlds: Cosmology and Wormholes

摘要： 我们利用嵌入渐近AdS${}_5$时空中的膜宇宙构建了四维平坦的大爆炸-大坍缩宇宙学和反德西特（AdS）平面永恒可穿越虫洞。 背景几何分别是AdS${}_5$磁性黑洞膜和磁荷AdS${}_5$溶解子。 这两种设置来源于引力欧几里得路径积分中同一鞍点的不同解析延拓，在此膜宇宙表现为Maldacena-Maoz欧几里得虫洞。 我们展示了该设置在微观欧几里得边界共形场论（BCFT）上的全息对偶描述，该BCFT定义在一个条带上。 通过分析BCFT欧几里得路径积分，我们表明膜宇宙宇宙学编码在与黑洞膜微态对应的CFT激发态中，而膜宇宙虫洞则编码在BCFT的基态中。 后者在红外区域被限制，我们使用全息方法研究其限制性质。 我们还评论了两种洛伦兹图景中的体重建性质及其通过双重解析延拓的关系。 这项工作可以解释为全息理论中宇宙学、可穿越虫洞和限制之间关系的显式双全息实现，这一关系最早在arXiv:2102.05057, arXiv:2203.11220中提出。 显示英文摘要

摘要： We construct 4D flat Big Bang-Big Crunch cosmologies and Anti-de Sitter (AdS) planar eternally traversable wormholes using braneworlds embedded in asymptotically AdS${}_5$ spacetimes. The background geometries are the AdS${}_5$ magnetic black brane and the magnetically charged AdS${}_5$ soliton, respectively. The two setups arise from different analytic continuations of the same saddle of the gravitational Euclidean path integral, in which the braneworld takes the form of a Maldacena-Maoz Euclidean wormhole. We show the existence of a holographic dual description of this setup in terms of a microscopic Euclidean boundary conformal field theory (BCFT) on a strip. By analyzing the BCFT Euclidean path integral, we show that the braneworld cosmology is encoded in a pure excited state of a CFT dual to a black brane microstate, whereas the braneworld wormhole is encoded in the ground state of the BCFT. The latter confines in the IR, and we study its confining properties using holography. We also comment on the properties of bulk reconstruction in the two Lorentzian pictures and their relationship via double analytic continuation. This work can be interpreted as an explicit, doubly-holographic realization of the relationship between cosmology, traversable wormholes, and confinement in holography, first proposed in arXiv:2102.05057, arXiv:2203.11220.