On a Bernstein-Sato polynomial of a meromorphic function

Abstract

We define Bernstein-Sato polynomials for meromorphic functions and study their basic properties. In particular, we prove a Kashiwara-Malgrange type theorem on their geometric monodromies, which would be useful also in relation with the monodromy conjecture. A new feature in the meromorphic setting is that we have several b-functions whose roots yield the same set of the eigenvalues of the Milnor monodromies. We introduce also multiplier ideal sheaves for meromorphic functions and show that their jumping numbers are related to our b-functions.