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arXiv · 0712.0752

A Mathematical Justification for the Herman-Kluk Propagator

Torben Swart·Vidian Rousse
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Abstract

A class of Fourier Integral Operators which converge to the unitary group of the Schroedinger equation in semiclassical limit $\eps\to 0$ is constructed. The convergence is in the uniform operator norm and allows for an error bound of order $O(\eps^{1-ρ})$ for Ehrenfest timescales, where $ρ$ can be made arbitrary small. For the shorter times of order O(1), the error can be improved to arbitrary order in $\eps$. In the chemical literature the approximation is known as the Herman-Kluk propagator.

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Torben Swart, Vidian Rousse. 2007-12-21. A Mathematical Justification for the Herman-Kluk Propagator. https://arxiv.org/abs/0712.0752

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