Holography and black holes in asymptotically flat FLRW

TL;DR

This paper extends the understanding of holographic symmetries in asymptotically flat FLRW spacetimes, introducing deformations of known algebras and a logarithmic ansatz to include cosmological black holes, connecting these to flat space counterparts.

Contribution

It introduces deformations of asymptotic algebras and a new ansatz to incorporate cosmological black holes in FLRW spacetimes, linking them to flat space holographic symmetries.

Findings

Identification of deformed asymptotic algebras in FLRW

Extension of holographic algebra to include Diff(S^2) transformations

Introduction of a logarithmic ansatz for cosmological black holes

Abstract

In this paper, we extend the treatment of asymptotically decelerating spatially flat FLRW spacetimes initiated in [1]. We show that a certain class of those metrics is ruled by the asymptotic algebra $\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$, which belongs to a one-parameter family of deformations of $\mathfrak{b}\mathfrak{m}\mathfrak{s}$. Furthermore, we enlarge our ansatz to include $\text{Diff}(S^2)$ transformations whose asymptotic algebra $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ is a one parameter deformation of $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}$. Therefore, the holographic algebras $\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ and $\mathfrak{g}\mathfrak{b}\mathfrak{m}\mathfrak{s}_s$ in FLRW can be related to their flat counterparts through a cosmological holographic flow. Finally, we introduce a logarithmic ansatz in order to account for cosmological black holes, which does not generally satisfy the peeling property but preserves the asymptotic algebra.