English

Driven active matter: fluctuations and a hydrodynamic instability

Soft Condensed Matter 2019-02-15 v1

Abstract

Wet active matter in the presence of an imposed temperature gradient, or chemical potential gradient, is considered. It is shown that there is a new type of convective instability that is caused by a (negative) activity parameter. Physically this corresponds to active fluids with contractual stress. In this non-equilibrium steady state the singular generic long-ranged correlations are computed and compared with the analogous results in a passive fluid. In addition, the singular non-equlibirum Casimir pressure or force is determined. The fluid motion above the instability is determined by generalizing the Lorenz equations for the Rayleigh-Benard instability in a passive fluid to Lorenz-like equations to describe this new instability.

Keywords

Cite

@article{arxiv.1902.05415,
  title  = {Driven active matter: fluctuations and a hydrodynamic instability},
  author = {T. R. Kirkpatrick and J. K. Bhattacherjee},
  journal= {arXiv preprint arXiv:1902.05415},
  year   = {2019}
}

Comments

accepted for publication in PRfluids. arXiv admin note: substantial text overlap with arXiv:1801.06820

R2 v1 2026-06-23T07:41:05.326Z