Parameter shift in normal generalized hypergeometric systems. (English) Zbl 0768.33016

Saito, Mutsumi

Tôhoku Math. J., II. Ser. 44, No. 4, 523-534 (1992).

Summary: We treat the problem of shifting parameters of \({\mathcal A}\)-hypergeometric systems when their associated toric varieties are normal. In this context we define and determine the Bernstein-Sato polynomials for the natural morphisms of shifting parameters. They are not Bernstein-Sato polynomials in a usual sense. We also give some examples.

MSC:

33C70	Other hypergeometric functions and integrals in several variables
14M25	Toric varieties, Newton polyhedra, Okounkov bodies
16W50	Graded rings and modules (associative rings and algebras)
39B32	Functional equations for complex functions

Keywords:

\(b\)-function; normal tonic variety; hypergeometric systems; Bernstein- Sato polynomials

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