Picard-Vessiot and categorically normal extensions in differential-difference Galois theory. (English) Zbl 1404.12008

Janelidze, G.

Bull. Belg. Math. Soc. - Simon Stevin 23, No. 5, 753-768 (2016).

Summary: The connection between categorical and differential Galois theories established by the author (published in 1989) is extended to the context that includes difference Galois theory.

MSC:

12H10	Difference algebra
12H05	Differential algebra
18A40	Adjoint functors (universal constructions, reflective subcategories, Kan extensions, etc.)
18A99	General theory of categories and functors

Keywords:

categorical Galois theory; difference Galois theory; differential Galois theory; Galois groupoid; normal extension; difference equation; differential equation; Wronski determinant; Casorati determinant