With a view to understanding extended-BMS symmetries in the framework of the AdS 4 /CFT 3 correspondence, asymptotically AdS geometries are constructed with null impulsive shockwaves involving a discontinuity in superrotation parameters. The holographic dual is proposed to be a two-dimensional Euclidean defect conformal field localized on a particular timeslice in a three-dimensional conformal field theory on de Sitter spacetime. The defect conformal field theory generates a natural action of the Virasoro algebra. The large radius of curvature limit ℓ → ∞ yields spacetimes with nontrivial extended-BMS charges corresponding to a single set of Virasoro charges.

中文翻译：

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通过 AdS/CFT 实现 BMS 对称

为了理解 AdS 4 /CFT 3 对应框架中的扩展 BMS 对称性，渐近 AdS 几何结构是用涉及超旋转参数不连续性的零脉冲冲击波构建的。全息对偶被提议为在德西特时空的三维共形场理论中位于特定时间片上的二维欧几里得缺陷共形场。缺陷共形场理论产生 Virasoro 代数的自然作用。大曲率半径 ℓ → ∞ 产生具有非平凡扩展 BMS 电荷的时空，对应于一组 Virasoro 电荷。