Oblique Projections, Biorthogonal Riesz Bases and Multiwavelets in Hilbert Spaces
نویسنده
چکیده
In this paper, we obtain equivalent conditions relating oblique projections to biorthogonal Riesz bases and angles between closed linear subspaces of a Hilbert space. We also prove an extension theorem in the biorthogonal setting, which leads to biorthogonal multiwavelets.
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