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arXiv · 2406.07748

Conformable Derivative Approach to Granular Gases

José Weberszpil·Cresus F. de L. Godinho·Ion Vasile Vancea
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Abstract

Proper modeling of complex systems requires innovative mathematical tools. In this sense, we sought to use deformed or fractal derivatives for studying the dynamics of systems, particularly those, such as granular gases, in which the description of the dynamics can be done by using the stretched exponential probability densities. In this contribution we draw up three results of this application of mathematical tools. The first result shows that when we use constraints with finite momentum and the principle of maximum entropy, the Kohlrausch--Williams--Watts function, known as stretched exponential, emerges naturally and in a simpler way, when compared to results in the literature. Next, we obtain generalized expressions for the Langevin equation, as well as its solutions for three different deformed derivatives, including those connected with nonaddictive statistical mechanics. The Haff's-like law for granular gases are obtained. Next, we calculate the partition function $Z$ for a granular gas system by building up the probability density in terms of the stretched exponential function. From this partition function, we determine the internal energy of the system as well as the specific heat, both dependent on temperature. The consistency with classical approach of kinetic theory for ideal gases was verified.

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José Weberszpil, Cresus F. de L. Godinho, Ion Vasile Vancea. 2024-06-25. Conformable Derivative Approach to Granular Gases. https://arxiv.org/abs/2406.07748

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