ArticleOriginal scientific text
Title
Two remarks about Picard-Vessiot extensions and elementary functions
Authors 1
Affiliations
- Institute of Mathematics, University of Warsaw, Banacha 2, 02-097 Warszawa, Poland
Abstract
We present a simple proof of the theorem which says that for a series of extensions of differential fields K ⊂ L ⊂ M, where K ⊂ M is Picard-Vessiot, the extension K ⊂ L is Picard-Vessiot iff the differential Galois group is a normal subgroup of . We also present a proof that the probability function Erf(x) is not an elementary function.
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