Codimension-one minimal extensions onto Haar subspaces (Q1759361)

Let \(H_n\) be an \(n\)-dimensional Haar subspace of \(C_{\mathbb{R}}[a,b]\) and \(H_{n-1}\) be an \((n-1)\)-dimensional Haar subspace of \(H_n\). Let \(A\) be a linear, continuous operator on \(H_{n-1}\). The authors show that, if a norm of minimal extension of \(A\) from \(H_n\) into \(H_{n-1}\) is greater than the operator norm of \(A\), then it is a strongly unique minimal extension.