Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nikulin involutions on K3 surfaces   We study the maps induced on cohomology by a Nikulin (i.e. a symplectic)
involution on a K3 surface. We parametrize the eleven dimensional irreducible
components of the moduli space of algebraic K3 surfaces with a Nikulin
involution and we give examples of the general K3 surface in various
components. We conclude with some remarks on Morrison-Nikulin involutions,
these are Nikulin involutions which interchange two copies of E_8(-1) in the
Neron Severi group.

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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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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: math-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph