TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.13.3.074
TI  - A splash in a one-dimensional cold gas
PY  - 2022/09/29
UR  - https://scipost.org/SciPostPhys.13.3.074
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 13
IS  - 3
SP  - 074
A1  - Chakraborti, Subhadip
AU  - Dhar, Abhishek
AU  - Krapivsky, Paul
AB  - We consider a set of hard point particles distributed uniformly with a specified density on the positive half-line and all initially at rest. The particle masses alternate between two values, $m$ and $M$. The particles interact via collisions that conserve energy and momentum. We study the cascade of activity that results when the left-most particle is given a positive velocity. At long times we find that this leads to two fascinating features in the observed dynamics. First, in the bulk of the gas, a shock front develops separating the cold gas from a thermalized region. The shock-front travels sub-ballistically, with the bulk described by self-similar solutions of Euler hydrodynamics. Second, there is a splash region formed by the recoiled particles which move ballistically with negative velocities. The splash region is completely non-hydrodynamic and we propose two conjectures for the long time particle dynamics in this region. We provide a detailed analytic understanding of these coexisting regimes. These are supported by the results of molecular dynamics simulations.
ER  -

@Article{10.21468/SciPostPhys.13.3.074,
	title={{A splash in a one-dimensional cold gas}},
	author={Subhadip Chakraborti and Abhishek Dhar and P. L. Krapivsky},
	journal={SciPost Phys.},
	volume={13},
	pages={074},
	year={2022},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.13.3.074},
	url={https://scipost.org/10.21468/SciPostPhys.13.3.074},
}