TOPICS
Search

Carl Neumann Criterion

Let A be a unital Banach algebra. If a in A and ||1-a||<1, then a^(-1) can be represented by the series sum_(n=0)^(infty)(1-a)^n. This criterion for checking invertibility of a is called Carl Neumann criterion.

This entry contributed by Mohammad Sal Moslehian

Explore with Wolfram|Alpha

References

Murphy, G. J. C-*-Algebras and Operator Theory. New York: Academic Press, 1990.

Referenced on Wolfram|Alpha

Carl Neumann Criterion

Cite this as:

Moslehian, Mohammad Sal. "Carl Neumann Criterion." From MathWorld--A Wolfram Web Resource, created by Eric W. Weisstein. https://mathworld.wolfram.com/CarlNeumannCriterion.html

Subject classifications