Arbitrarily long-lived quasinormal modes in a wormhole background

TL;DR

This paper demonstrates the existence of arbitrarily long-lived quasi-resonance modes in wormhole backgrounds, except in specific cases, supported by frequency and time domain analyses showing dominance of these modes at large field masses.

Contribution

It extends the concept of quasi-resonances from black holes to wormholes, identifying conditions under which these long-lived modes occur.

Findings

Quasi-resonances exist in wormhole backgrounds unless the red-shift function is constant.

Frequency and time domain analyses are consistent in detecting these modes.

Long-lived modes dominate the wave signal at large field masses after power-law tails.

Abstract

Arbitrarily long lived modes, called quasi-resonances, are known to exist in the spectrum of massive fields for a number of black-hole backgrounds at some discrete values of mass of the field. Here we show that these modes also exist in the background of wormholes, unless a wormhole has a constant red-shift function, that is, tideless in the radial direction. The evidence of quasi-resonances is supported by calculations in the frequency and time domains, which are in a good concordance. At large masses of the field, time-domain profiles of the absolute value of the wave function have peculiar behavior: the long-lived modes dominate in the signal after a long period of power-law tails.