Thermostatistical analysis and negative heat capacities of Yukawa and Lee-Wick potentials in noncommutative phase spaces

Abstract

In recent years, physical models based on noncommutative algebras have attracted considerable interest, as they provide a natural framework to incorporate a fundamental scale, often associated with semiclassical aspects of quantum gravity. Noncommutative geometry modifies the underlying phase-space structure, potentially leading to new insights into unresolved problems in theoretical physics. In this work, we adopt a semiclassical approach to perform a thermostatistical analysis of well-established interaction models, namely the Yukawa and Lee--Wick potentials, within a noncommutative phase space. We investigate how phase-space deformations affect the density of states, partition function, mean energy, and heat capacity, considering both microcanonical and canonical ensembles within the Boltzmann--Gibbs framework. Our results show that the introduction of the noncommutative parameter $Θ$ induces nontrivial modifications in thermodynamic quantities, including qualitative changes in the heat capacity. In particular, regions with negative heat capacity may emerge, which we interpret as signatures of the limitations of the semiclassical and perturbative treatment rather than definitive physical effects. The analysis is carried out under the assumption of weak noncommutativity and $|βV(r)| \ll 1$, which constrains the regime of validity of the results. Within this domain, our findings highlight the role of phase-space geometry in shaping thermodynamic behavior.