On the joint spectra of doubly commuting n-tuples of semi-normal operators

On the Spectra of Semi-normal Operators

m-Isometric Commuting Tuples of Operators on a Hilbert Space

We consider a generalization of isometric Hilbert space operators to the multivariable setting. We study some of the basic properties of these tuples of commuting operators and we explore several examples. In particular, we show that the d-shift, which is important in the dilation theory of d-contractions (or row contractions), is a d-isometry. As an application of our techniques we prove a the...

Probability of Mutually Commuting N-Tuples in Some Classes of Compact Groups

Joint Extensions in Families of Contractive Commuting Operator Tuples

In this paper we systematically study extension questions in families of commuting operator tuples that are associated with the unit ball in C.

the effect of taftan pozzolan on the compressive strength of concrete in the environmental conditions of oman sea (chabahar port)

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...