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arXiv · 2305.03847

Evolution of the wave-function's shape in a time-dependent harmonic potential

Etera R. Livine
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Abstract

An effective operational approach to quantum mechanics is to focus on the evolution of wave-packets, for which the wave-function can be seen in the semi-classical regime as representing a classical motion dressed with extra degrees of freedom describing the shape of the wave-packet and its fluctuations. These quantum dressing are independent degrees of freedom, mathematically encoded in the higher moments of the wave-function. We review how to extract the effective dynamics for Gaussian wave-packets evolving according to the Schrodinger equation with time-dependent potential in a 1+1-dimensional spacetime, and derive the equations of motion for the quadratic uncertainty. We then show how to integrate the evolution of all the higher moments for a general wave-function in a time-dependent harmonic potential.

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Etera R. Livine. 2023-05-05. Evolution of the wave-function's shape in a time-dependent harmonic potential. https://doi.org/10.1209/0295-5075%2Facedcc

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