6 citations · 11 across the 4 of their papers we have counts for
10 papers
Powers of posinormal operators
C. S. Kubrusly, P. C. M. Vieira, J. Zanni
Square of a posinormal operator is not necessarily posinormal But (i) powers of quasiposinormal operators are quasiposinormal and, under closed ranges assumption, powers of (ii)…
Algebraic Tensor Products Revisited: Axiomatic Approach
C. S. Kubrusly
This is an expository paper on tensor products where the standard approaches for constructing concrete instances of algebraic tensor products of linear spaces, via quotient spaces…
Asymptotic limits, Banach limits, and Cesàro means
C. S. Kubrusly, B. P. Duggal
Every new inner product in a Hilbert space is obtained from the original one by means of a unique positive operator The first part of the paper is a survey on applications of su…
Boundedly Spaced Subsequences and Weak Dynamics
C. S. Kubrusly, P. C. M. Vieira
The purpose of this paper is to characterize weak supercyclicity for Hilbert-space contractions, which is shown to be equivalent to characterizing weak supercyclicity for unitary o…
Biisometric operators and biorthogonal sequences
Carlos S. Kubrusly, Nhan Levan
It is shown that a pair of Hilbert space operators V and W such that V*W=I (called a biisometric pair) shares some common properties with unilateral shifts when orthonormal basis a…
Power bounded -left invertible operators
B. P. Duggal, C. S. Kubrusly
A Hilbert space operator $S\in\B$ is left -invertible by $T\in\B$ if is -isometric if…