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arXiv · 2311.02780

Revivals in time-evolution quasi-periodic problems

George Farmakis
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Abstract

We examine the influence of quasi-periodic boundary conditions on the phenomenon of revivals in linear dispersive PDEs. We show that, in general, quasi-periodic problems do not support the revival effect at rational times. Our method is based on a correspondence between quasi-periodic and periodic problems. We prove that the solution to a quasi-periodic problem is expressed via the solution to a corresponding periodic problem, and vice-versa. Then, our main results follow by deriving a representation of the periodic problem solution in terms of a composition of solutions for a particular class of periodic problems, where the latter supports the classical revival and fractalisation dichotomy at rational and irrational times.

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George Farmakis. 2023-11-05. Revivals in time-evolution quasi-periodic problems. https://arxiv.org/abs/2311.02780

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