String Theory Journal Club

I will discuss causality on a holographic screen in static patch (SP) holography of asymptotically de Sitter spacetimes. SP holography is one proposal of dS holography, however, its boundary description is mysterious due to the lack of concrete models in three or higher dimensions. Nevertheless, we can argue various properties including causality without relying on the detail of the theory by employing a theorem that holds generically in holography — the connected wedge theorem. It assures from quantum information that entanglement on the boundary when direct scattering in the bulk does not have a local boundary analog. We argue that based on the theorem, the causality on the holographic screen for SP holography should be induced from a point on null infinities (either future or past, depending on the sign of the momentum). This hints us toward a connection between two different dS holography proposals, SP holography and dS/CFT. This talk is based on my recent work with Victor Franken. The paper is available on arXiv: https://arxiv.org/abs/2410.09050.