Currently displaying 1 – 15 of 15

Showing per page

Order by Relevance | Title | Year of publication

Unbounded Hermitian operators and relative reproducing kernel Hilbert space

Palle Jorgensen — 2010

Open Mathematics

We study unbounded Hermitian operators with dense domain in Hilbert space. As is known, the obstruction for a Hermitian operator to be selfadjoint or to have selfadjoint extensions is measured by a pair of deficiency indices, and associated deficiency spaces; but in practical problems, the direct computation of these indices can be difficult. Instead, in this paper we identify additional structures that throw light on the problem. We will attack the problem of computing deficiency spaces for a single...

Wavelets on fractals.

Dorin E. DutkayPalle E.T. Jorgensen — 2006

Revista Matemática Iberoamericana

We show that there are Hilbert spaces constructed from the Hausdorff measures H on the real line R with 0 < s < 1 which admit multiresolution wavelets. For the case of the middle-third Cantor set C ⊂ [0,1], the Hilbert space is a separable subspace of L(R, (dx)) where s = log(2). While we develop the general theory of multiresolutions in fractal Hilbert spaces, the emphasis is on the case of scale 3 which covers the traditional Cantor set C.

Matrices induced by arithmetic functions, primes and groupoid actions of directed graphs

Ilwoo ChoPalle E. T. Jorgensen — 2015

Special Matrices

In this paper, we study groupoid actions acting on arithmetic functions. In particular, we are interested in the cases where groupoids are generated by directed graphs. By defining an injective map α from the graph groupoid G of a directed graph G to the algebra A of all arithmetic functions, we establish a corresponding subalgebra AG = C*[α(G)]︀ of A. We construct a suitable representation of AG, determined both by G and by an arbitrarily fixed prime p. And then based on this representation, we...

A C * -algebraic Schoenberg theorem

Ola BratteliPalle E. T. JorgensenAkitaka KishimotoDonald W. Robinson — 1984

Annales de l'institut Fourier

Let 𝔄 be a C * -algebra, G a compact abelian group, τ an action of G by * -automorphisms of 𝔄 , 𝔄 τ the fixed point algebra of τ and 𝔄 F the dense sub-algebra of G -finite elements in 𝔄 . Further let H be a linear operator from 𝔄 F into 𝔄 which commutes with τ and vanishes on 𝔄 τ . We prove that H is a complete dissipation if and only if H is closable and its closure generates a C 0 -semigroup of completely positive contractions. These complete dissipations are classified in terms of certain twisted negative definite...

Page 1

Download Results (CSV)