Statistical mechanics description of an empirical scenario in which gravity was discussed when coupled to a harmonic oscillator.

We attempt to construct a (two-dimensional) statistical mechanics description of the scenario in which the experiment in [T. Westphal <italic>et al.</italic>, <italic>Nature</italic> <bold>591</bold>, 225 (2021)] was made. It includes two masses that, simultaneously, (1) interact classically via the Newton gravitation and (2) harmonically vibrate. Within the strictures of Gibbs canonical ensemble at the temperature <italic>T</italic>, our treatment is exact. [ABSTRACT FROM AUTHOR]