A simple almost-periodicity criterion and applications. (English) Zbl 0608.34049

Haraux, A.

J. Differ. Equations 66, 51-61 (1987).

A simple sufficient condition for almost periodicity of functions \(u: {\mathbb{R}}\to X\) into a complete metric space X is observed and exploited for solutions of periodic linear ordinary differential equations in a Euclidean space (e.g. Hill’s equation) and trajectories of periodic processes on a complete metric space (e.g. semilinear partial differential equations).

Reviewer: D.Erle

MSC:

34C27	Almost and pseudo-almost periodic solutions to ordinary differential equations
34A30	Linear ordinary differential equations and systems

Keywords:

first order differential equation; trajectories of periodic processes; complete metric space

References:

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