Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bridging the microscopic and the hydrodynamic in active filament
  solutions   Hydrodynamic equations for an isotropic solution of active polar filaments
are derived from a microscopic mean-field model of the forces exchanged between
motors and filaments. We find that a spatial dependence of the motor stepping
rate along the filament is essential to drive bundle formation. A number of
differences arise as compared to hydrodynamics derived (earlier) from a
mesoscopic model where relative filament velocities were obtained on the basis
of symmetry considerations. Due to the anisotropy of filament diffusion, motors
are capable of generating net filament motion relative to the solvent. The
effect of this new term on the stability of the homogeneous state is
investigated.

19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th