Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exact coherent structures and phase space geometry of pre-turbulent 2D
  active nematic channel flow   Confined active nematics exhibit rich dynamical behavior, including
spontaneous flows, periodic defect dynamics, and chaotic `active turbulence'.
Here, we study these phenomena using the framework of Exact Coherent
Structures, which has been successful in characterizing the routes to high
Reynolds number turbulence of passive fluids. Exact Coherent Structures are
stationary, periodic, quasiperiodic, or traveling wave solutions of the
hydrodynamic equations that, together with their invariant manifolds, serve as
an organizing template of the dynamics. We compute the dominant Exact Coherent
Structures and connecting orbits in a pre-turbulent active nematic channel
flow, which enables a fully nonlinear but highly reduced order description in
terms of a directed graph. Using this reduced representation, we compute
instantaneous perturbations that switch the system between disparate
spatiotemporal states occupying distant regions of the infinite dimensional
phase space. Our results lay the groundwork for a systematic means of
understanding and controlling active nematic flows in the moderate to high
activity regime.

11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th