Moment Closure Approximations of the Boltzmann Equation Based on $$\varphi $$φ-Divergences

  title={Moment Closure Approximations of the Boltzmann Equation Based on \$\$\varphi \$\$$\phi$-Divergences},
  author={M. R. A. Abdelmalik and E. H. van Brummelen},
  journal={Journal of Statistical Physics},
This paper is concerned with approximations of the Boltzmann equation based on the method of moments. We propose a generalization of the setting of the moment-closure problem from relative entropy to $$\varphi $$φ-divergences and a corresponding closure procedure based on minimization of $$\varphi $$φ-divergences. The proposed description encapsulates as special cases Grad’s classical closure based on expansion in Hermite polynomials and Levermore’s entropy-based closure. We establish that the… 

A moment closure based on a projection on the boundary of the realizability domain: Extension and analysis

  • T. Pichard
  • Mathematics
    Kinetic and Related Models
  • 2022
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