Abstract
Let H be a linear unbounded operator in a Hilbert space. It is assumed that the resolvent of H is a compact operator and H - H is a Hilbert-Schmidt operator. Various integro-differential operators satisfy these conditions. It is shown that H is similar to a normal operator and a sharp bound for the condition number is suggested. We also discuss applications of that bound to spectrum perturbations and operator functions.
| Original language | English |
|---|---|
| Pages (from-to) | 331-342 |
| Number of pages | 12 |
| Journal | Journal of the Australian Mathematical Society |
| Volume | 97 |
| Issue number | 3 |
| DOIs | |
| State | Published - 20 Jun 2014 |
Keywords
- condition numbers
- norm of operator function
- operators
- similarity
- spectrum perturbations
ASJC Scopus subject areas
- General Mathematics