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arXiv · 0801.2491

Dynamics of Annihilation II: Fluctuations of Global Quantities

P. Maynar·M. I. Garcia de Soria·G. Schehr·A. Barrat·E. Trizac
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Abstract

We develop a theory for fluctuations and correlations in a gas evolving under ballistic annihilation dynamics. Starting from the hierarchy of equations governing the evolution of microscopic densities in phase space, we subsequently restrict to a regime of spatial homogeneity, and obtain explicit predictions for the fluctuations and time correlation of the total number of particles, total linear momentum and total kinetic energy. Cross-correlations between these quantities are worked out as well. These predictions are successfully tested against Molecular Dynamics and Monte-Carlo simulations. This provides strong support for the theoretical approach developed, including the hydrodynamic treatment of the spectrum of the linearized Boltzmann operator. This article is a companion paper to arXiv:0801.2299 and makes use of the spectral analysis reported there.

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P. Maynar, M. I. Garcia de Soria, G. Schehr, A. Barrat, E. Trizac. 2008-01-16. Dynamics of Annihilation II: Fluctuations of Global Quantities. https://doi.org/10.1103/physreve.77.051128

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