The spectral and Fredholm theory of extensions of bounded linear operators
The spectral and Fredholm theory of extensions of bounded linear operators
Assume $T$ is a bounded linear operator on some Banach space $Y$, and that $T$ has a bounded extension $\bar T$ on another space. In general almost nothing can be said concerning the relationship between the spectral and Fredholm properties of $T$ and $\bar T$. However, assuming the special condition …