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arXiv · 0705.2975

On the Definitions of Difference Galois Groups

Zoé Chatzidakis·Charlotte Hardouin·Michael F. Singer
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Abstract

We compare several definitions of the Galois group of a linear difference equation that have arisen in algebra, analysis and model theory and show, that these groups are isomorphic over suitable fields. In addition, we study properties of Picard-Vessiot extensions over fields with not necessarily algebraically closed subfields of constants.

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Zoé Chatzidakis, Charlotte Hardouin, Michael F. Singer. 2007-05-21. On the Definitions of Difference Galois Groups. https://arxiv.org/abs/0705.2975

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