Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The characteristic class and ramification of an l-adic etale sheaf   We introduce the characteristic class of an l-adic etale sheaf using a
cohomological pairing due to Verdier (SGA5). As a consequence of the
Lefschetz-Verdier trace formula, its trace computes the Euler-Poincare
characteristic of the sheaf. We compare the characteristic class to two other
invariants arising from ramification theory. One is the Swan class of
Kato-Saito (math.AG/0402010) and the other is the 0-cycle class defined by Kato
for rank 1 sheaves.

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The categories of this paper are: nucl-th
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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: solv-int
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: q-alg
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The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: cs