Nonequilibrium phase transitions in active contractile polar filaments

Kripa Gowrishankar; Madan Rao

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arXiv · 1201.3938

Nonequilibrium phase transitions in active contractile polar filaments

Kripa Gowrishankar·Madan Rao

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Abstract

We study the patterning and fluctuations of a collection of active contractile polar filaments on a two dimensional substrate, using a continuum description in the presence of athermal noise, parameterised by an active temperature $T_A$. The steady states generically consist of arrays of inward pointing asters and show a continuous transition from a moving aster street to a stationary aster lattice. In contrast to its equilibrium counterpart, this active crystal shows true long range order at low $T_A$. On increasing $T_A$, the asters remodel with a distribution of lifetimes; concomitantly we find novel phase transitions characterised by polar and bond-orientational order.

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Kripa Gowrishankar, Madan Rao. 2012-01-18. Nonequilibrium phase transitions in active contractile polar filaments. https://arxiv.org/abs/1201.3938

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