Noshort scalar hair theorem for spinning acoustic black holes in a photonfluid model
Abstract
It has recently been revealed that spinning black holes of the photonfluid model can support acoustic `clouds'—stationary density fluctuations whose spatially regular radial eigenfunctions are determined by the (2 +1 )dimensional KleinGordon equation of an effective massive scalar field. Motivated by this intriguing observation, we use analytical techniques in order to prove a noshort hair theorem for the composed acoustic black hole scalarclouds configurations. In particular, it is proved that the effective lengths of the stationary boundstate corotating acoustic scalar clouds are bounded from below by the series of inequalities r_{hair}>1/+√{5 } 2 .r_{H}>r_{null} , where r_{H} and r_{null} are respectively the horizon radius of the supporting black hole and the radius of the corotating null circular geodesic that characterizes the acoustic spinning black hole spacetime.
 Publication:

Physical Review D
 Pub Date:
 November 2021
 DOI:
 10.1103/PhysRevD.104.104041
 arXiv:
 arXiv:2202.00688
 Bibcode:
 2021PhRvD.104j4041H
 Keywords:

 General Relativity and Quantum Cosmology;
 Astrophysics  High Energy Astrophysical Phenomena;
 High Energy Physics  Theory
 EPrint:
 8 pages