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arXiv · 1310.7658

Asymptotic-preserving exponential methods for the quantum Boltzmann equation with high-order accuracy

Jingwei Hu·Qin Li·Lorenzo Pareschi
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Abstract

In this paper we develop high-order asymptotic-preserving methods for the spatially inhomogeneous quantum Boltzmann equation. We follow the work in Li and Pareschi, where asymptotic preserving exponential Runge-Kutta methods for the classical inhomogeneous Boltzmann equation were constructed. A major difficulty here is related to the non Gaussian steady states characterizing the quantum kinetic behavior. We show that the proposed schemes work with high-order accuracy uniformly in time for all Planck constants ranging from classical regime to quantum regime, and all Knudsen numbers ranging from kinetic regime to fluid regime. Computational results are presented for both Bose gas and Fermi gas.

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Jingwei Hu, Qin Li, Lorenzo Pareschi. 2013-10-29. Asymptotic-preserving exponential methods for the quantum Boltzmann equation with high-order accuracy. https://arxiv.org/abs/1310.7658

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