Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A topological obstruction to the controllability of nonlinear wave
  equations with bilinear control term   In this paper we prove that the Ball-Marsden-Slemrod controllability
obstruction also holds for nonlinear equations, with integrable bilinear
controls. We first show an abstract result and then we apply it to nonlinear
wave equations. The first application to the Sine-Gordon equation directly
follows from the abstract result, and the second application concerns the cubic
wave/Klein-Gordon equation and needs some additional work.

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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
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The categories of this paper are: physics
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: solv-int