Fake Structures in dS Holography

In this talk, I will explore the role of fake structures—not regions where physical degrees of freedom exist, but rather effective auxiliary regions introduced to make manifest the symmetries of those degrees of freedom—in the context of de Sitter (dS) holography. While the notion of holography is well-established in AdS, its realization in dS spacetimes remains elusive. A central challenge lies in the observer-dependent nature of horizons and the absence of a globally defined boundary.

Drawing on insights from the double-scaled SYK model (DSSYK), I will argue that certain emergent geometric features—such as the fake circle—arising in its semi-classical limit encode effective degrees of freedom behind cosmological horizons, in a manner analogous to the reconstruction of the black hole interior from the outside. By examining the classical limit of DSSYK, I will demonstrate how such structures can provide a consistent quantum gravitational interpretation of bulk reconstruction in de Sitter space.