Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Chevalley theorem for difference equations   By a theorem of Chevalley the image of a morphism of varieties is a
constructible set. The algebraic version of this fact is usually stated as a
result on "extension of specializations" or "lifting of prime ideals". We
present a difference analog of this theorem. The approach is based on the
philosophy that occasionally one needs to pass to higher powers of $\sigma$,
where $\sigma$ is the endomorphism defining the difference structure. In other
words, we consider difference pseudo fields (which are finite direct products
of fields) rather than difference fields. We also prove a result on
compatibility of pseudo fields and present some applications of the main
theorem, e.g. constrained extension and uniqueness of differential
Picard-Vessiot rings with a difference parameter.

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The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: comp-gas