Unruh-DeWitt detector in dimensionally-reduced static spherically symmetric spacetimes

Understand

We study the dynamics of an Unruh-DeWitt detector interacting with a massless scalar field in an arbitrary static spherically symmetric spacetimes whose metric is characterised by a single metric function $f(r)$.

• In order to obtain clean physical insights, we employ the derivative coupling variant of the Unruh-DeWitt model in (1+1) dimensions where powerful conformal techniques enable closed-form expressions for the vacuum two-point functions.
• Due to the generality of the formalism, we will be able to study a very general class of static spherically symmetric (SSS) background.
• We pick three examples to illustrate our method: (1) non-singular Hayward black holes, (2) the recently discovered $D\to 4$ limit of Gauss-Bonnet black holes, and (3) the "black bounce" metric that interpolates Schwarzschild black holes and traversable wormholes.