Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chronology protection in a toy surface plasmon "time machine"   Recently introduced toy surface plasmon "black holes" and "wormholes" (New
Journal of Physics 5, 147.1-147.8 (2003), and gr-qc/0306089) can be used to
create a toy "time machine" according to a number of published designs (see for
example I.D. Novikov, Sov.Phys.JETP 68, 439 (1989)). Assuming that such a toy
"time machine" does not work, a general prediction can be made of strong
electromagnetic field enhancement inside an arbitrarily-shaped nanohole near an
arising effective event horizon, which is supposed to prevent the toy "time
machine" from being operational. This general result is useful in description
of the nonlinear optical behavior of random nanoholes in metal films.

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The categories of this paper are: plasm-ph
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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: econ
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-th
1
The categories of this paper are: cs
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The categories of this paper are: funct-an
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
2
The categories of this paper are: math