Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Driven active matter: fluctuations and a hydrodynamic instability   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.

28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin