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arXiv · 1302.7185

A Generalization of Fermat's Principle for Classical and Quantum Systems

Tarek A. Elsayed
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Abstract

The analogy between dynamics and optics had a great influence on the development of the foundations of classical and quantum mechanics. We take this analogy one step further and investigate the validity of Fermat's principle in many-dimensional spaces describing dynamical systems (i.e., the quantum Hilbert space and the classical phase and configuration space). We propose that if the notion of a metric distance is well defined in that space and the velocity of the representative point of the system is an invariant of motion, then a generalized version of Fermat's principle will hold. We substantiate this conjecture for time-independent quantum systems and for a classical system consisting of coupled harmonic oscillators. An exception to this principle is the configuration space of a charged particle in a constant magnetic field; in this case the principle is valid in a frame rotating by half the Larmor frequency, not the stationary lab frame.

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Tarek A. Elsayed. 2014-09-23. A Generalization of Fermat's Principle for Classical and Quantum Systems. https://doi.org/10.1016/j.physleta.2014.09.032

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