we investigate compact composition operators on ceratin lipschitzspaces of analytic functions on the closed unit disc of the plane.our approach also leads to some results about compositionoperators on zygmund type spaces.

We determine the extended eigenvalues and extended eigenvectors of weighted shifts. We also describe the structure of Deddens algebras and spectral radius algebras associated to weighted shifts. In particular, we show that these algebras are weakly dense in the algebra of all bounded linear operators or in the algebra of lower triangular operators.

We discuss (extended) super Schrödinger algebras obtained as subalgebras of the superconformal algebra psu(2,2|4). The Schrödinger algebra with two spatial dimensions can be embedded into so(4,2). In the superconformal case the embedded algebra may be enhanced to the so-called super Schrödinger algebra. In fact, we find an extended super Schrödinger subalgebra of psu(2,2|4). It contains 24 supe...

We discuss (extended) super Schrödinger algebras which are subalgebras of the superconformal algebra psu(2,2|4). The Schrödinger algebra with two spatial dimensions can be embedded into so(4,2). In the superconformal case the embedded algebra may be enhanced to the so-called super Schrödinger algebra. In fact, we find an extended super Schrödinger subalgebra of psu(2,2|4). It contains, as well ...

the present study aims at indicating the existence and uniqueness result of system in extended colombeaualgebra. the caputo fractional derivative is used for solving the system of odes. in addition, rieszfractional derivative of colombeau generalized algebra is considered. the purpose of introducing rieszfractional derivative is regularizing it in colombeau sense. we also give a solution to a n...

Let θ ∈ [0, 1] be any irrational number. It is shown that the extended rotation algebra Bθ introduced in [8] is always an AF algebra.

The purpose of this article is to establish Jackson-type inequality in the polydiscs UN of C for holomorphic spaces X, such as Bergman-type spaces, Hardy spaces, polydisc algebra and Lipschitz spaces. Namely, E k(f,X) (−→ 1/k, f,X ) , where E k(f,X) is the deviation of the best approximation of f ∈ X by polynomials of degree at most kj about the jth variable zj with respect to the X-metric and ...

Any MV-algebra M can be embedded as a lattice in the Boolean algebra B(M) that is R-generated by M . We relate the study of states on an MV-algebra M to the study of finitely additive probabilities on B(M). In particular, we show that each state on M can be uniquely extended to a finitely additive probability on B(M). In case that M is a PMV-algebra, the conditional state s(a|b) defined for a, ...

A subset X of a real Hilbert space H is said to be proximally smooth provided that the function d X : H ! R (the distance to X) is continuously diierentiable on an open tube U around X. It is proven that this property is equivalent to d X having a nonempty proximal subgradient at every point of U, and that the (G^ ateaux = Fr echet) derivative is locally Lipschitz on U. The Lipschitz behavior o...

By a quantum metric space we mean a C∗-algebra (or more generally an order-unit space) equipped with a generalization of the usual Lipschitz seminorm on functions which one associates to an ordinary metric. We develop for compact quantum metric spaces a version of Gromov–Hausdorff distance. We show that the basic theorems of the classical theory have natural quantum analogues. Our main example ...