GJC: Robin Croft "Gravitational Echoes in Einstein-Maxwell-Scalar Theory"

Tuesday 15 Apr 2025, 13:00 → 14:00 Europe/Rome

Sala Lauree (Marconi)

Einstein Maxwell scalar (EMS) theory, which combines electromagnetism with a real scalar field through a dilaton coupling, permits hairy black hole (BH) solutions. In the perturbative regime, these hairy BHs are known to posses a double peaked potential capable of producing echoes in the quasi-normal mode (QNM) spectrum. We will discuss some recent work comparing echoes (for scalar QNMs) in the linear regime to a fully non-linear 1+1 numerical relativity (NR) simulation. Following this, we will outline the formalism used for simulating the EMS system in NR and give a look at some work in progress towards EMS BH collisions in 2D using GRChombo; these headon collisions aim to probe the phenomenology of echoes in a scenario very far from a perturbative regime.