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arXiv · 1705.06392

On a problem by Hans Feichtinger

Radu Balan·Kasso A. Okoudjou·Anirudha Poria
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Abstract

In this paper, we solve a spectral problem about positive semi-definite trace-class pseudodifferential operators on modulation spaces which was posed by H. Feichtinger. Later, C. Heil and D. Larson rephrased the problem in the broader setting of positive semi-definite trace-class operators on a separable Hilbert space. Our solution consists in constructing a counterexample that solves Hans Feichtinger's problem by first solving this second problem.

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Radu Balan, Kasso A. Okoudjou, Anirudha Poria. 2017-05-18. On a problem by Hans Feichtinger. https://doi.org/10.7153/oam-2018-12-53

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