Group Riesz and Frame Sequences: The Bracket and the Gramian
arXiv:1608.02767
Abstract
Given a discrete group and a unitary representation on a Hilbert space $\mathcal{H}$, we prove that the notions of operator Bracket map and Gramian coincide on a dense set of $\mathcal{H}$. As a consequence, combining this result with known frame theory, we can recover in a simple way all previous Bracket characterizations of Riesz and frame sequences generated by a single element under a unitary representation.
arXiv admin note: text overlap with arXiv:1506.08942