All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 45 Next

Displaying 881 – 900 of 3251

Showing per page

Extensions of symmetric operators I: The inner characteristic function case

R.T.W. Martin (2015)

Concrete Operators

Given a symmetric linear transformation on a Hilbert space, a natural problem to consider is the characterization of its set of symmetric extensions. This problem is equivalent to the study of the partial isometric extensions of a fixed partial isometry. We provide a new function theoretic characterization of the set of all self-adjoint extensions of any symmetric linear transformation B with finite equal indices and inner Livšic characteristic function θB by constructing a bijection between the...

Extensions of the representation theorems of Riesz and Fréchet

João C. Prandini (1993)

Mathematica Bohemica

We present two types of representation theorems: one for linear continuous operators on space of Banach valued regulated functions of several real variables and the other for bilinear continuous operators on cartesian products of spaces of regulated functions of a real variable taking values on Banach spaces. We use generalizations of the notions of functions of bounded variation in the sense of Vitali and Fréchet and the Riemann-Stieltjes-Dushnik or interior integral. A few applications using geometry...

Extreme compact operators from Orlicz spaces to C ( Ω )

Shutao Chen, Marek Wisła (1993)

Commentationes Mathematicae Universitatis Carolinae

Let E ϕ ( μ ) be the subspace of finite elements of an Orlicz space endowed with the Luxemburg norm. The main theorem says that a compact linear operator T : E ϕ ( μ ) → C ( Ω ) is extreme if and only if T * ω ∈ Ext B ( ( E ϕ ( μ ) ) * ) on a dense subset of Ω , where Ω is a compact Hausdorff topological space and 〈 T * ω , x 〉 = ( T x ) ( ω ) . This is done via the description of the extreme points of the space of continuous functions C ( Ω , L ϕ ( μ ) ) , L ϕ ( μ ) being an Orlicz space equipped with the Orlicz norm (conjugate to the Luxemburg one). There is also given a theorem on closedness of the set of extreme...

Factoring Rosenthal operators.

Teresa Alvarez (1988)

Publicacions Matemàtiques

In this paper we show that a Rosenthal operator factors through a Banach space containing no isomorphs of l1.

Currently displaying 881 – 900 of 3251