On the Dynamics of Near-Extremal Black Holes

Understand

We analyse the dynamics of near-extremal Reissner-Nordstr\"om black holes in asymptotically four-dimensional Anti-de Sitter space (AdS$_4$).

• We work in the spherically symmetric approximation and study the thermodynamics and the response to a probe scalar field.
• We find that the behaviour of the system, at low energies and to leading order in our approximations, is well described by the Jackiw-Teitelboim (JT) model of gravity.
• In fact, this behaviour can be understood from symmetry considerations and arises due to the breaking of time reparametrisation invariance.