# ON A TOPOLOGICAL DIVISOR OF ZERO IN THE CALKIN ALGEBRA

• Lee, Hong-Youl (Department of Mathematics Education, Woosuk University)
• Published : 2006.08.01
• 69 3

#### Abstract

We give a simple proof of the statement that if T is a bounded linear operator on a complex HIlbert space then T is Fredholm if and only if ${\pi}(T)$ is not a TDZ, where ${\pi}(\cdot)$ is the Catkin homomorphism.

#### Keywords

Fredholm operators;topological divisor of zeros

#### References

1. R. E. Harte, Invertibility and singularity for bounded linear operators, Dekker, New York, 1988