Orthonormal Jordan bases in finite dimensional Hilbert spaces

Operator-valued bases on Hilbert spaces

In this paper we develop a natural generalization of Schauder basis theory, we term operator-valued basis or simply ov-basis theory, using operator-algebraic methods. We prove several results for ov-basis concerning duality, orthogonality, biorthogonality and minimality. We prove that the operators of a dual ov-basis are continuous. We also dene the concepts of Bessel, Hilbert ov-basis and obta...

g-Bases in Hilbert Spaces

and Applied Analysis 3 Definition 2.6. We say {Λj ∈ B H,Hj }j 1 is g-orthonormal basis for H with respect to {Hj}, if it is g-biorthonormal with itself and for any f ∈ H one has

Universitet Orthonormal bases for - modulation spaces

We construct an orthonormal basis for the family of bi-variate α-modulation spaces. The construction is based on local trigonometric bases, and the basis elements are closely related to so-called brushlets. As an application, we show that m-term nonlinear approximationwith the system in an α-modulation space can be completely characterized.

New characterizations of fusion bases and Riesz fusion bases in Hilbert spaces

In this paper we investigate a new notion of bases in Hilbert spaces and similar to fusion frame theory we introduce fusion bases theory in Hilbert spaces. We also introduce a new denition of fusion dual sequence associated with a fusion basis and show that the operators of a fusion dual sequence are continuous projections. Next we dene the fusion biorthogonal sequence, Bessel fusion basis, Hil...

Pointwise Bounds for Orthonormal Basis Elements in Hilbert Spaces