139 citations · 140 across the 8 of their papers we have counts for
8 papers
k-hyponormality of multivariable weighted shifts
Raul E. Curto, Sang Hoon Lee, Jasang Yoon
We characterize joint k-hyponormality for 2-variable weighted shifts. Using this characterization we construct a family of examples which establishes and illustrates the gap betwee…
Solution of the truncated hyperbolic moment problem
Raul E. Curto, Lawrence A. Fialkow
Let Q(x,y)=0 be an hyperbola in the plane. Given real numbers , with , the truncated Q-hyperbolic moment problem for βenta…
Truncated K-moment problems in several variables
Raul E. Curto, Lawrence A. Fialkow
Let be an N-dimensional real multi-sequence of degree 2n, with associated moment matrix , and let …
k-hyponormality of finite rank perturbations of unilateral weighted shifts
Raul E. Curto, Woo Young Lee
In this paper we explore finite rank perturbations of unilateral weighted shifts . First, we prove that the subnormality of is never stable under nonzero finite rank per…
Jointly hyponormal pairs of commuting subnormal operators need not be jointly subnormal
Raul Curto, Jasang Yoon
We construct three different families of commuting pairs of subnormal operators, jointly hyponormal but not admitting commuting normal extensions. Each such family can be used to a…
k-hyponormality of powers of weighted shifts via Schur products
Raul E. Curto, Sang Soo Park
We characterize -hyponormality and quadratic hyponormality of powers of weighted shifts using Schur product techniques.