Speaker
Description
If relativistic gravitation has a quantum description, it must be meaningful to consider a spacetime metric in a quantum superposition. But how might such a superposition be described, and how could observers detect it? I will present an operational framework for studying “superpositions of spacetimes” via indirect measurements, on particles residing in such spacetime. After presenting the general approach, I show how it can be applied to a black hole placed in a superposition of masses where the dynamics of the particle exhibits signatures of quantum-gravitational effects reminiscent of Bekenstein’s seminal conjecture concerning the quantized mass spectrum of black holes in quantum gravity. I will close with remarks on the importance of distinguishing scenarios that are genuinely quantum-gravitational, notably with reference to recent proposals to test gravitationally-induced entanglement.
