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arXiv · 1302.1505

Multivariate Difference-Differential Dimension Polynomials and New Invariants of Difference-Differential Field Extensions

Alexander Levin
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Abstract

In this paper we introduce a method of characteristic sets with respect to several term orderings for difference-differential polynomials. Using this technique, we obtain a method of computation of multivariate dimension polynomials of finitely generated difference-differential field extensions. Furthermore, we find new invariants of such extensions and show how the computation of multivariate difference-differential polynomials is applied to the equivalence problem for systems of algebraic difference-differential equations.

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Alexander Levin. 2013-02-06. Multivariate Difference-Differential Dimension Polynomials and New Invariants of Difference-Differential Field Extensions. https://arxiv.org/abs/1302.1505

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