A falling magnetic monopole as a holographic local quench

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.