Quantum Systems in Weak Gravitational Fields

G. Papini

Magdalena Zych

LV Lin

The low-temperature properties of an idea and a weakly interacting Fermi gas in homogenous gravitational field are studied,based on the semiclassical(Thomas-Fermi) approximation and local-density approximation.The general analytical expressions of several thermodynamic quantities have been derived.The free system,idea system in homogenous gravitational field,and interacting system in homogenous gravitational field are compared.The effects of gravitational field and interparticle interactions on properties of Fermi gas are discussed.

Kaito Kashiwagi, Akira Matsumura

We investigate the dissipative dynamics of a two-level atom in a weak gravitational field. Using the Feynman--Vernon influence functional formalism, we derive a quantum master equation describing the two-level atom interacting with a scalar field in a Newtonian gravitational field, and compute the energy dissipation rate of the atom. We find that the spontaneous emission rate (the dissipation rate in vacuum) is modified by the gravitational field. Specifically, this modification depends on the atom's dipole, the position of the atom relative to the source of the gravitational field, and the frequency of the scalar radiation emitted by the atom. Furthermore, we identify the parameter regimes in which the spontaneous emission rate is enhanced or suppressed by gravity. We also discuss how the modification arises from time dilation and dipole radiation in a weak gravitational field. These findings provide a theoretical basis for exploring gravitational effects in open quantum systems.

Martine Schut

Gaetano Lambiase, G. Papini