Classical computational spectral problem
= Classical computational spectral problem
The classical computational spectral problem takes $\Omega=\mathcal B(\ell^2(\mathbb N))$, reads the matrix entries $\langle Ae_j,e_i\rangle$, and asks for $\operatorname{Sp}(A)$ in the <Hausdorff distance> or <Attouch--Wets topology>. Its <Solvability complexity index> is three for general bounded operators.