Oblique projections and frames
نویسندگان
چکیده
منابع مشابه
Oblique Projections and Abstract Splines
Given a closed subspace S of a Hilbert space H and a bounded linear operator A ∈ L(H) which is positive, consider the set of all A-selfadjoint projections onto S P(A,S) = {Q ∈ L(H) : Q2 = Q , Q(H) = S , AQ = Q∗A}. In addition, if H1 is another Hilbert space, T : H → H1 is a bounded linear operator such that T ∗T = A and ξ ∈ H, consider the set of (T,S) spline interpolants to ξ: sp (T,S, ξ) = {η...
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LetH be a Hilbert space, L(H) the algebra of all bounded linear operators onH and 〈, 〉A : H ×H → C the bounded sesquilinear form induced by a selfadjoint A ∈ L(H), 〈ξ, η〉A = 〈Aξ, η〉 , ξ, η ∈ H. Given T ∈ L(H), T is A-selfadjoint if AT = T A. If S ⊆ H is a closed subspace, we study the set of A-selfadjoint projections onto S, P(A,S) = {Q ∈ L(H) : Q = Q , R(Q) = S , AQ = QA} for different choices...
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Given a frame for a subspace W of a Hilbert space H, we consider a class of oblique dual frame sequences. These dual frame sequences are not constrained to lie in W . Our main focus is on shift-invariant frame sequences of the form {φ(· − k)}k∈Z in subspaces of L2(R); for such frame sequences we are able to characterize the set of shift-invariant oblique dual Bessel sequences. Given frame seque...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2005
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-05-08143-8