Oscillons and quasi-breathers in D+1 dimensions

TL;DR

This paper investigates oscillons and quasi-breathers across various spatial dimensions, revealing how their properties and stability depend on the number of dimensions, with implications for their existence and longevity.

Contribution

It introduces a numerical method to determine quasi-breather solutions in D+1 dimensions and analyzes their energy, frequency dependence, and decay behavior.

Findings

Energy of quasi-breathers has a minimum depending on dimensions

Oscillons decay into quasi-breathers before disappearing

Possible absence of oscillons for dimensions greater than 5

Abstract

We study oscillons in D+1 space-time dimensions using a spherically symmetric ansatz. From Gaussian initial conditions, these evolve by emitting radiation, approaching ``quasi-breathers'', near-periodic solutions to the equations of motion. Using a truncated mode expansion, we numerically determine these quasi-breather solutions in 2<D<6 and the energy dependence on the oscillation frequency. In particular, this energy has a minimum, which in turn depends on the number of spatial dimensions. We study the time evolution and lifetimes of the resulting quasi-breathers, and show how generic oscillons decay into these before disappearing altogether. We comment on the apparent absence of oscillons for D>5 and the possibility of stable solutions for D<2.