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arXiv · 0904.3355

On sigma-delta-Picard-Vessiot extensions

Ana Peón-Nieto
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Abstract

We study the differential Galois theory of difference equations under weaker hypothesis on the field of constants of the automorphism. This framework yields a new approach to results by C.Hardouin and M.Singer, which answers possitively a question by M.Singer: under the classical hypothesis, the known results are still valid. In particular, our Galois group is isomorphic to theirs over a suitable field. We also explicitly calculate the number of connected components of the Galois group.

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Ana Peón-Nieto. 2009-04-21. On sigma-delta-Picard-Vessiot extensions. https://doi.org/10.1080/00927871003645391

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