Correlations in Ballistic Processes

E. Trizac; P. L. Krapivsky

doi:10.1103/physrevlett.91.218302

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Correlations in Ballistic Processes

E. Trizac·P. L. Krapivsky

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Abstract

We investigate a class of reaction processes in which particles move ballistically and react upon colliding. We show that correlations between velocities of colliding particles play a crucial role in the long time behavior. In the reaction-controlled limit when particles undergo mostly elastic collisions and therefore are always near equilibrium, the correlations are accounted analytically. For ballistic aggregation, for instance, the density decays as $n\sim t^{-ξ}$ with $ξ=2d/(d+3)$ in the reaction-controlled limit in $d$ dimensions, in contrast with well-known mean-field prediction $ξ=2d/(d+2)$.

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E. Trizac, P. L. Krapivsky. 2003-10-07. Correlations in Ballistic Processes. https://doi.org/10.1103/physrevlett.91.218302

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