Energy Flow in Acoustic Black Holes

TL;DR

This paper analyzes the energy flow caused by scalar fields interacting with an acoustic black hole, confirming superradiance and detailing the energy profile outside the horizon.

Contribution

It provides a detailed analysis of energy flow in acoustic black holes, confirming superradiant behavior and explicitly characterizing energy flux directions.

Findings

Energy flows inward at the horizon and outward at infinity.

Confirms superradiant energy amplification.

Provides detailed energy profile outside the horizon.

Abstract

We present the results of an analysis of superradiant energy flow due to scalar fields incident on an acoustic black hole. In addition to providing independent confirmation of the recent results in [5], we determine in detail the profile of energy flow everywhere outside the horizon. We confirm explicitly that in a suitable frame the energy flow is inward at the horizon and outward at infinity, as expected on physical grounds.