Evidencing Quantum Gravity with Thermodynamical Observables

TL;DR

This paper proposes using thermodynamical measurements, specifically heat capacity, of a gravitationally self-interacting Bose gas to empirically distinguish between classical and quantum gravity effects in a tabletop experiment.

Contribution

It introduces a novel method to infer quantum gravity through macroscopic thermodynamical observables, avoiding the need for quantum control of individual systems.

Findings

Heat capacity differs significantly between classical and quantum gravity models.

The approach provides a feasible experimental signature for quantum gravity.

Demonstrates the potential of thermodynamics to reveal quantum gravitational effects.

Abstract

Proposed experiments for obtaining empirical evidence for a quantum description of gravity in a table-top setting focus on detecting quantum information signatures, such as entanglement or non-Gaussianity production, in gravitationally interacting quantum systems. Here, we explore an alternative approach where the quantization of gravity could be inferred through measurements of macroscopic, thermodynamical quantities, without the need for addressability of individual quantum systems. To demonstrate the idea, we take as a case study a gravitationally self-interacting Bose gas, and consider its heat capacity. We find a clear-cut distinction between the predictions of a classical gravitational interaction and a quantum gravitational interaction in the heat capacity of the Bose gas.