Yang-Mills instanton on a four dimensional wormhole: asymptotic stability in the energy space
Michał Kowalczyk, Javier Monreal
TL;DR
This work analyzes SU(2) Yang-Mills dynamics on a 4+1 dimensional wormhole, reducing to a 1D semilinear wave equation with a kink as a distinguished stationary solution. It proves conditional asymptotic stability of the degree-one kink under small odd perturbations in the energy space, delivering precise decay on finite intervals and weighted global decay. The authors develop a robust virial framework with tailored weights to overcome the algebraic decay of the linearized operator, including a Darboux-type transformation to produce a repulsive potential and ensure coercivity. The results advance the understanding of soliton-like stability on wormhole geometries and showcase the versatility of virial methods for problems with slow dispersive decay.
Abstract
In this paper we consider an $SU(2)$ Yang-Mills field propagating in the $4+1$ dimensional wormhole spacetime. Assuming the spherically symmetric magnetic ansatz the problem reduces to a one dimensional non linear wave equation. This equation posses a degree one solution (instanton) which is odd in space. We consider small, odd perturbations of the instanton and show that it is conditionally asymptotically stable in the odd energy space.
