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arXiv · 0711.2217

Time propagation of constrained coupled Gaussian wave packets

T. Fabcic·J. Main·G. Wunner
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Abstract

The dynamics of quantum systems can be approximated by the time propagation of Gaussian wave packets. Applying a time dependent variational principle, the time evolution of the parameters of the coupled Gaussian wave packets can be calculated from a set of ordinary differential equations. Unfortunately, the set of equations is ill-behaved in most practical applications, depending on the number of propagated Gaussian wave packets, and methods for regularization are needed. We present a general method for regularization based on applying adequate nonholonomic inequality constraints to the evolution of the parameters, keeping the equations of motion well-behaved. The power of the method is demonstrated for a non-integrable system with two degrees of freedom.

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T. Fabcic, J. Main, G. Wunner. 2007-11-14. Time propagation of constrained coupled Gaussian wave packets. https://doi.org/10.1063/1.2821751

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