Hamiltonian deformations of Gabor frames: First steps.

Appl Comput Harmon Anal

University of Vienna, Faculty of Mathematics, NuHAG, Austria.

Published: March 2015

Gabor frames can advantageously be redefined using the Heisenberg-Weyl operators familiar from harmonic analysis and quantum mechanics. Not only does this redefinition allow us to recover in a very simple way known results of symplectic covariance, but it immediately leads to the consideration of a general deformation scheme by Hamiltonian isotopies ( arbitrary paths of non-linear symplectic mappings passing through the identity). We will study in some detail an associated weak notion of Hamiltonian deformation of Gabor frames, using ideas from semiclassical physics involving coherent states and Gaussian approximations. We will thereafter discuss possible applications and extensions of our method, which can be viewed - as the title suggests - as the very first steps towards a general deformation theory for Gabor frames.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4394155PMC
http://dx.doi.org/10.1016/j.acha.2014.03.010DOI Listing

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