4 problems

Curto–Muhly–Xia conjecture. The pair $\mathbf{T}$ is subnormal if and only if it is hyponormal.

Let $\zeta_1,\zeta_2,\zeta_3$ be any three distinct points on the unit circle, let $c_1,c_2,c_3$ be positive real numbers, and set … Let $M_z$ denote multiplication by $z$ on…

For a complex separable Hilbert space $\mathcal H$, let $S\in\mathcal L(\mathcal H)$ be a subnormal operator with minimal normal extension $N$, and let $\mu$ be the scalar-valued s…

Let $T_\phi$ be a scalar Toeplitz operator on the Hardy space whose self-commutator $[T_\phi^*,T_\phi]$ has finite rank. Normal-or-analytic conjecture. If $T_\phi$ is subnormal, th…