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arXiv · 1302.5257

Stable Self-Interacting Pais-Uhlenbeck Oscillator

Matej Pavšič
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Abstract

It is shown that the interacting Pais-Uhlenbeck oscillator necessarily leads to a description with a Hamiltonian that contains positive and negative energies associated with two oscillators. Descriptions with a positive definite Hamiltonians, considered by some authors, can hold only for a free Pais-Uhlenbeck oscillator. We demonstrate that the solutions of a self-interacting Pais-Uhlenbeck oscillator are stable on islands in the parameter space, as already observed in the literature. If we slightly modify the system, by considering a sine interaction term, and/or by taking unequal masses of the two oscillators, then the system is stable on the continents that extend from zero to infinity in the parameter space. Therefore, the Pais-Uhlenbeck oscillator is quite acceptable physical system.

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Matej Pavšič. 2013-11-08. Stable Self-Interacting Pais-Uhlenbeck Oscillator. https://doi.org/10.1142/s0217732313501654

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