A falling magnetic monopole as a holographic local quench

TL;DR

This paper constructs a holographic model of a local quench using a falling magnetic monopole in AdS space, revealing unique entanglement entropy dynamics distinct from black hole quenches.

Contribution

It introduces an analytic static monopole solution in AdS4 and maps it to a falling monopole, providing new insights into local quenches and entanglement evolution in holography.

Findings

Energy-momentum tensor matches black hole quench form

Entanglement entropy shows competition between scalar condensate and quasiparticles

Distinct entanglement spread behavior from black hole quenches

Abstract

An analytic static monopole solution is found in global AdS$_4$, in the limit of small backreaction. This solution is mapped in Poincar\'e patch to a falling monopole configuration, which is dual to a local quench triggered by the injection of a condensate. Choosing boundary conditions which are dual to a time-independent Hamiltonian, we find the same functional form of the energy-momentum tensor as the one of a quench dual to a falling black hole. On the contrary, the details of the spread of entanglement entropy are very different from the falling black hole case where the quench induces always a higher entropy compared to the vacuum, i.e. $\Delta S >0$. In the propagation of entanglement entropy for the monopole quench, there is instead a competition between a negative contribution to $\Delta S$ due to the scalar condensate and a positive one carried by the freely propagating quasiparticles generated by the energy injection.