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Title: Ladder symmetries of black holes and de Sitter space: love numbers and quasinormal modes
Abstract

In this note, we present a synopsis of geometric symmetries for (spin 0) perturbations around (4D) black holes and de Sitter space. For black holes, we focus on static perturbations, for which the (exact) geometric symmetries have the group structure of SO(1,3). The generators consist of three spatial rotations, and three conformal Killing vectors obeying a specialmelodiccondition. The static perturbation solutions form a unitary (principal series) representation of the group. The recently uncovered ladder symmetries follow from this representation structure; they explain the well-known vanishing of the black hole Love numbers. For dynamical perturbations around de Sitter space, the geometric symmetries are less surprising, following from the SO(1,4) isometry. As is known, the quasinormal solutions form a non-unitary representation of the isometry group. We provide explicit expressions for the ladder operators associated with this representation. In both cases, the ladder structures help connect the boundary condition at the horizon with that at infinity (black hole) or origin (de Sitter space), and they manifest as contiguous relations of the hypergeometric solutions.

 
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Award ID(s):
2209997
PAR ID:
10522830
Author(s) / Creator(s):
; ;
Publisher / Repository:
Institute of Physics
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2023
Issue:
06
ISSN:
1475-7516
Page Range / eLocation ID:
056
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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