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arXiv · 1603.01478

Quantum expectations via spectrograms

Johannes Keller·Caroline Lasser·Tomoki Ohsawa
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Abstract

We discuss a new phase space method for the computation of quantum expectation values in the high frequency regime. Instead of representing a wavefunction by its Wigner function, which typically attains negative values, we define a new phase space density by adding a first-order Hermite spectrogram term as a correction to the Husimi function. The new phase space density yields accurate approximations of the quantum expectation values as well as allows numerical sampling from non-negative densities. We illustrate the new method by numerical experiments in up to $128$ dimensions.

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Johannes Keller, Caroline Lasser, Tomoki Ohsawa. 2016-03-04. Quantum expectations via spectrograms. https://arxiv.org/abs/1603.01478

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