Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental evidence for new symmetry axis of electromagnetic beams   The new symmetry axis of a well-behaved electromagnetic beam advanced in
paper Physical Review A 78, 063831 (2008) is not purely a mathematical concept.
The experimental result reported by Hosten and Kwiat in paper Science 319, 787
(2008) is shown to demonstrate the existence of this symmetry axis that is
neither perpendicular nor parallel to the propagation axis.

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The categories of this paper are: cmp-lg
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
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The categories of this paper are: nlin
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The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol