Emergence of Tsallis statistics in Thomas-Fermi theory
Phys. Rev. E 114, 034124 – Published 14 September, 2026
DOI: https://doi.org/10.1103/gvjq-tcrr
Abstract
This work establishes a direct connection between semiclassical Thomas-Fermi theory and Tsallis statistics. The kinetic energy term of the Thomas-Fermi framework is shown to be associated with the Tsallis entropy , while the particle interactions play the role of internal energy , allowing the Thomas-Fermi-Lenz functional to be interpreted as a free-energy functional within a generalized thermostatistical setting. Accordingly, the minimization of the energy functional is equivalent to a maximum-entropy principle. The entropic index is found to depend on spatial dimension: in the nonrelativistic case, in the ultrarelativistic limit, and under strong magnetic fields. A time-dependent hydrodynamic formulation leads to a nonlinear diffusion equation consistent with a nonlinear Fokker-Planck description. An anomalous diffusion characterized by a universal subdiffusive regime, independent of the spatial dimension, was identified. The time-dependent and time-independent results reveal a correspondence between Thomas-Fermi theory and Tsallis statistics, indicating that the former can be viewed as a generalized thermostatistics; Tsallis statistics is not assumed, it emerges from Thomas-Fermi theory.