Skip to main content

All Questions

Filter by
Sorted by
Tagged with
3 votes
1 answer
148 views

Is this sum of nonexpansive maps itself nonexpansive?

For Hilbert spaces $\mathcal{H}_X$, $\mathcal{H}_Y$ and $\mathcal{K}$, consider a linear map $f\colon \mathcal{K} \oplus \mathcal{H}_X \to \mathcal{K} \oplus \mathcal{H}_Y$ that is given as a matrix $...