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arXiv · 2009.10678

Quantum Polar Duality and the Symplectic Camel: a Geometric Approach to Quantization

Maurice de Gosson
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Abstract

We define and study the notion of quantum polarity, which is a kind of geometric Fourier transform between sets of positions and sets of momenta. Extending previous work of ours, we show that the orthogonal projections of the covariance ellipsoid of a quantum state on the configuration and momentum spaces form what we call a dual quantum pair. We thereafter show that quantum polarity allows solving the Pauli reconstruction problem for Gaussian wavefunctions. The notion of quantum polarity exhibits a strong interplay between the uncertainty principle and symplectic and convex geometry and our approach could therefore pave the way for a geometric and topological version of quantum indeterminacy. We relate our results to the Blaschke-Santal\'o inequality and to the Mahler conjecture. We also discuss the Hardy uncertainty principle and the less-known Donoho--Stark principle from the point of view of quantum polarity.

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Maurice de Gosson. 2020-09-22. Quantum Polar Duality and the Symplectic Camel: a Geometric Approach to Quantization. https://arxiv.org/abs/2009.10678

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