Variational methods for almost periodic solutions of a class of neutral delay equations. (English) Zbl 1149.34042

Summary: We provide new variational settings to study a.p. (almost periodic) solutions of a class of nonlinear neutral delay equations. We extend the variational setting for periodic solutions of nonlinear neutral delay equation by Shu and Xu (2006) to the almost periodic settings. We obtain results on the structure of the set of the a.p. solutions, results of existence of a.p. solutions, results on existence of a.p. solutions, and also a density result for the forced equations.


34K14 Almost and pseudo-almost periodic solutions to functional-differential equations
34K40 Neutral functional-differential equations
47J30 Variational methods involving nonlinear operators
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