Extensions of Hilbert modules and Hankel operators
type: Item
instance of: scholarly article
title: Extensions of Hilbert modules and Hankel operators
zbMATH Open document ID: 0974.47021
DOI: 10.1142/S0252959900000030
author: Kunyu Guo
published in: Chinese Annals of Mathematics. Series B
publication date: 2001-11-30T00:00:00Z
review text: The author studies extensions of the Hardy and Bergman modules over the disk algebra. He proves that \(\text{Ext} (L^2_a(D),H)\neq 0\) for any nonunitarily isometric module \(H\), and gives an explicit formula for \(\text{Ext} (L^2_a(D),H^2(D))\) in terms of symbol classes of certain Hankel operators. He proves as well that \(\text{Ext} (L^2_a(D),L^2_a(D))\neq 0\).
Mathematics Subject Classification ID: 47B35
Mathematics Subject Classification ID: 46H25
zbMATH DE Number: 1445757
zbMATH Keywords: Hilbert module
zbMATH Keywords: Hankel operator
zbMATH Keywords: disk algebra
zbMATH Keywords: symbol classes
zbMATH Keywords: Bergman modules
MaRDI profile type: Publication
description: scientific article; zbMATH DE number 1445757