Holomorphic Functional Calculus on Quotients of Fréchet Algebras and Michael's Problem
Language
en
Document de travail - Pré-publication
English Abstract
The purpose of the paper is to give the state of the art on Michael's problem, the long-standing open question odf continuity of characters on commutative Fréchet algebras. We first quote two well-known consequences of the ...Read more >
The purpose of the paper is to give the state of the art on Michael's problem, the long-standing open question odf continuity of characters on commutative Fréchet algebras. We first quote two well-known consequences of the "abstract Mittag-Leffler theorem", the theorem of Arens, which shows that characters on finitely rationally generated Fréchet algebras are continuous, and the fact that the existence of a nonincreasing sequence (Ωn) n≥1 of Fatou-Bieberbach domains in C p such that ∩ n≥1 Ωn = ∅ would imply that all characters on commutative Fréchet algebras are continuous. In the opposite direction the existence of a discontinuous character on some commutative unital Fréchet algebra is equivalent to the existence of a character on a quotient algebra of the form U/I where U is a 'test algebra' for Michael's problem and where I is a dense ideal of U which is a Picard-Borel ideal, which means that every family of pairwise linearly independent invertible elements of U/I is linearly independent. It was recently shown that all Picard-Borel ideals in commutative unital Fréchet algebras are prime, and Picard-Borel ideals of H(C) can be easily described. We raise a question concerning Picard-Borel ideals of H(C p), p ≥ 2 which could lead to important general information about the quotient of commutative unital Fréchet algebras by Picard-Borel ideals. The fact that entire functions of several variables oerate on quotients of Fréchet algebras by ideals which are not necessarily closed plays an essential role in the paper.Read less <
English Keywords
Borel theorem Picard theorem entire function Fréchet algebra Michael's problem prime ideal Picard-Borel ideal weak Picard-Borel ideal holomorphic functional calculus MSC: 30D20 30H50 32A15 46H10 46J05 N. Surname N. Surname: Short Title (pp. 1 -9)
Borel theorem
Picard theorem
entire function
Fréchet algebra
Michael's problem
prime ideal
Picard-Borel ideal
weak Picard-Borel ideal
holomorphic functional calculus MSC: 30D20
30H50
32A15
46H10
46J05 N. Surname
N. Surname: Short Title (pp. 1 -9)
Origin
Hal imported