Phase transitions in self-gravitating systems and bacterial populations with a screened attractive potential

P. H. Chavanis; L. Delfini

doi:10.1103/physreve.81.051103

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arXiv · 1001.1942

Phase transitions in self-gravitating systems and bacterial populations with a screened attractive potential

P. H. Chavanis·L. Delfini

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Abstract

We consider a system of particles interacting via a screened Newtonian potential and study phase transitions between homogeneous and inhomogeneous states in the microcanonical and canonical ensembles. Like for other systems with long-range interactions, we obtain a great diversity of microcanonical and canonical phase transitions depending on the dimension of space and on the importance of the screening length. We also consider a system of particles in Newtonian interaction in the presence of a ``neutralizing background''. By a proper interpretation of the parameters, our study describes (i) self-gravitating systems in a cosmological setting, and (ii) chemotaxis of bacterial populations in the original Keller-Segel model.

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P. H. Chavanis, L. Delfini. 2010-01-12. Phase transitions in self-gravitating systems and bacterial populations with a screened attractive potential. https://doi.org/10.1103/physreve.81.051103

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