Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transport barriers to self-propelled particles in fluid flows   We present theory and experiments demonstrating the existence of invariant
manifolds that impede the motion of microswimmers in two-dimensional fluid
flows. One-way barriers are apparent in a hyperbolic fluid flow that block the
swimming of both smooth-swimming and run-and-tumble \emph{Bacillus subtilis}
bacteria. We identify key phase-space structures, called swimming invariant
manifolds (SwIMs), that serve as separatrices between different regions of
long-time swimmer behavior. When projected into $xy$-space, the edges of the
SwIMs act as one-way barriers, consistent with the experiments.

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The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an