Nash-type equilibria and periodic solutions to nonvariational systems


The paper deals with variational properties of fixed points for contraction-type operators. Undersuitable conditions, the unique xed point of a vector-valued operator is a Nash-type equilibrium of thecorresponding energy functionals. This is achieved by an iterative scheme based on Ekeland’s variationalprinciple. An application to periodic solutions for second order dierential systems is given to illustratethe theory.


Radu Precup
Department of Mathematics Babes-Bolyai University, Cluj-Napoca, Romania


Nash-type equilibrium; fxed point; critical point; Ekeland principle; periodic solution; secondorder system

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R. Precup, Nash-type equilibria and periodic solutions to nonvariational systems, Adv. Nonlinear Anal., 3 (2014), no. 4,  197-207,


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Advances Nonlinear Analysis

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de Gruyter

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