Backreaction in an analogue black hole experiment
Abstract
In general relativity, the interaction between a black hole and the fields around it (a process known as backreaction) proceeds via the evolution of the black holes mass and angular momentum. Analogue models of gravity, particularly fluid mechanical analogues, have been very successful in mimicking the propagation of fields, and the effects they experience, around black holes. However, hydrodynamic black holes are externally driven systems whose effective mass and angular momentum are set by experimental parameters, and as such no significant internal backreaction processes are expected to take place. We show, using a rotating draining vortex flow, that a fluid system of finite size exhibits a memory that keeps track of scattering processes in the system. This memory is encoded in the total mass of the system and hence, the backreaction arises as a significant global change in the background parameters, as opposed to a small local correction. More importantly, this backreaction is encapsulated by a dynamical metric, raising the possibility of studying wavebackground interaction around evolving black hole spacetimes.
 Publication:

arXiv eprints
 Pub Date:
 May 2019
 DOI:
 10.48550/arXiv.1905.03045
 arXiv:
 arXiv:1905.03045
 Bibcode:
 2019arXiv190503045P
 Keywords:

 General Relativity and Quantum Cosmology;
 Quantum Physics
 EPrint:
 10 pages, 2 figures