Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: DiPerna-Lions flow for relativistic particles in an electromagnetic
  field   We show the existence and uniqueness of a DiPerna-Lions flow for relativistic
particles subject to a Lorentz force in an electromagnetic field. The electric
and magnetic fields solves the linear Maxwell system in the void but for
singular initial conditions. As the corresponding force field is only in $L^2$,
we have to perform a careful analysis of the cancellations over a trajectory.

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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: funct-an
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The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: hep-th
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The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin