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  • Open Access

Evidencing quantum gravity with thermodynamical observables

Thomas Strasser1,*, Marios Christodoulou1, Richard Howl2, and Časlav Brukner1,3

  • 1Institute for Quantum Optics and Quantum Information (IQOQI) Vienna, Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria
  • 2Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom
  • 3Vienna Center for Quantum Science and Technology (VCQ), Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria

  • *Contact author: thomas.strasser@mail.com
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Phys. Rev. Research 7, 043299 – Published 16 December, 2025

DOI: https://doi.org/10.1103/jdgg-hmcq

Abstract

Proposed experiments for obtaining empirical evidence for a quantum description of gravity in a tabletop 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.

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Phys. Rev. Research 7, 043299– Published 16 December, 2025
  • Received 15 January 2025
  • Accepted 19 September 2025
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