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arXiv · 2609.31521

Complexity drives the symmetry breaking of temperature fluctuations

D. Rosales Herrera·M. Y. Gallegos Ruiz·A. Fernández Téllez·J. R. Alvarado García·J. E. Ramírez
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Abstract

Frequently, nonextensive systems are described through $q$-exponential functions, where the $q$-parameter determines how far a system is from equilibrium. In this work, we study systems constrained to $q-1\ll1$ to describe systems near thermal equilibrium, and derive the probability density function and temperature fluctuations. To this end, we derive the series expansion of the $q$-exponential function, yielding a perturbative series that is a superposition of gamma distributions. On the other hand, the temperature fluctuations are expressed as a superposition of Dirac delta functions and their derivatives, meaning that the bulk of the system remains at a constant temperature, while point-temperature variations emerge, marking the system's departure from thermal equilibrium. The statistics of the temperature fluctuations exhibit a transition from a symmetric to a nonsymmetric distribution as the nonextensive parameter increases. These results provide evidence of the association between the emergence of nonextensivity and the symmetry breaking of temperature fluctuations.

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D. Rosales Herrera, M. Y. Gallegos Ruiz, A. Fernández Téllez, J. R. Alvarado García, J. E. Ramírez. 2026-09-25. Complexity drives the symmetry breaking of temperature fluctuations. https://doi.org/10.1103/hmzl-jh2h

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