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arXiv · 1703.03660

Duality for Frames in Krein Spaces

J. I. Giribet·A. Maestripieri·Francisco Martínez Pería
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Abstract

A $J$-frame for a Krein space $\mathcal{H}$ is in particular a frame for $\mathcal{H}$ (in the Hilbert space sense). But it is also compatible with the indefinite inner-product of $\mathcal{H}$, meaning that it determines a pair of maximal uniformly definite subspaces, an analogue to the maximal dual pair associated to an orthonormal basis in a Krein space. This work is devoted to study duality for $J$-frames in Krein spaces. Also, tight and Parseval $J$-frames are defined and characterized.

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J. I. Giribet, A. Maestripieri, Francisco Martínez Pería. 2017-03-10. Duality for Frames in Krein Spaces. https://arxiv.org/abs/1703.03660

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