Unbounded 2-hyperexpansive operators

被引：37

作者：

Jablonski, ZJ ^{[1
]}

Stochel, J ^{[1
]}

机构：

[1] Jagiellonian Univ, Inst Matemat, PL-30059 Krakow, Poland

来源：

PROCEEDINGS OF THE EDINBURGH MATHEMATICAL SOCIETY | 2001年 / 44卷

关键词：

unbounded operators; closedness of powers of operators; 2-hyperexpansive operators; 2-isometries; paranormal operators; weighted shifts;

D O I：

10.1017/S001309159900139X

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

It is shown that most properties of (bounded) completely hyperexpansive operators remain valid for unbounded 2-hyperexpansive operators. Powers of closed 2-hyperexpansive operators are proved to be closed and 2-hyperexpansive. Various parts of spectra of such operators are calculated. 2-hyperexpansive weighted shifts are investigated. Examples of unbounded closed 2-hyperexpansive (2-isometric) operators with invariant dense domains are established.

引用

页码：613 / 629

页数：17