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arXiv · 1211.3360

Tight projections of frames on infinite dimensional Hilbert spaces

John Jasper
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Abstract

We characterize the frames on an infinite dimensional separable Hilbert space that can be projected to a tight frame for an infinite dimensional subspace. A result of Casazza and Leon states that an arbitrary frame for a 2N- or (2N-1)-dimensional Hilbert space can be projected to a tight frame for an N-dimensional subspace. Surprisingly, we demonstrate a large class of frames for infinite dimensional Hilbert spaces which cannot be projected to a tight frame for any infinite dimensional subspace.

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John Jasper. 2012-11-14. Tight projections of frames on infinite dimensional Hilbert spaces. https://arxiv.org/abs/1211.3360

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