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arXiv · 0903.4122

The Jeans Mechanism and Bulk-Viscosity Effects

Nakia Carlevaro·Giovanni Montani
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Abstract

In this paper we study the gravitational instability in presence of viscosity. In particular, the standard Jeans Mechanism is analyzed taking into account bulk-viscosity effects in the first-order Newtonian dynamics. We show how the perturbation evolution is damped by dissipative processes and the top-down fragmentation mechanism is suppressed for strong viscous effects. The critical value of the Jeans Mass remains unchanged also in presence of bulk viscosity.

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Nakia Carlevaro, Giovanni Montani. 2009-03-24. The Jeans Mechanism and Bulk-Viscosity Effects. https://arxiv.org/abs/0903.4122

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