## Abstract and Applied Analysis

### Bourgin-Yang-type theorem for $a$-compact perturbations of closed operators. Part I. The case of index theories with dimension property

#### Abstract

A variant of the Bourgin-Yang theorem for $a$-compact perturbations of a closed linear operator (in general, unbounded and having an infinite-dimensional kernel) is proved. An application to integrodifferential equations is discussed.

#### Article information

Source
Abstr. Appl. Anal., Volume 2006, Special Issue (2006), Article ID 78928, 13 pages.

Dates
First available in Project Euclid: 19 March 2007

https://projecteuclid.org/euclid.aaa/1174321752

Digital Object Identifier
doi:10.1155/AAA/2006/78928

Mathematical Reviews number (MathSciNet)
MR2217211

Zentralblatt MATH identifier
1130.47037

#### Citation

Antonyan, Sergey A.; Balanov, Zalman I.; Gel'man, Boris D. Bourgin-Yang-type theorem for $a$ -compact perturbations of closed operators. Part I. The case of index theories with dimension property. Abstr. Appl. Anal. 2006, Special Issue (2006), Article ID 78928, 13 pages. doi:10.1155/AAA/2006/78928. https://projecteuclid.org/euclid.aaa/1174321752

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