The Cerenkov effect revisited: from swimming ducks to zero modes in gravitational analogs

TL;DR

This paper provides an interdisciplinary review of the generalized Cerenkov effect across various physical systems, highlighting how dispersion laws influence emission patterns and their implications for gravitational analogs.

Contribution

It introduces a geometric method to analyze Cerenkov emission patterns based on dispersion laws, applicable across multiple physical contexts and experimental setups.

Findings

Unified geometric framework for Cerenkov emission patterns

Application to superfluid and hydrodynamic systems

Implications for stability of gravitational analogs

Abstract

We present an interdisciplinary review of the generalized Cerenkov emission of radiation from uniformly moving sources in the different contexts of classical electromagnetism, superfluid hydrodynamics, and classical hydrodynamics. The details of each specific physical systems enter our theory via the dispersion law of the excitations. A geometrical recipe to obtain the emission patterns in both real and wavevector space from the geometrical shape of the dispersion law is discussed and applied to a number of cases of current experimental interest. Some consequences of these emission processes onto the stability of condensed-matter analogs of gravitational systems are finally illustrated.