## Abstract

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.

## Authors

**Radu Precup**

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

## Keywords

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

## Paper coordinates

R. Precup, *Nash-type equilibria and periodic solutions to nonvariational systems*, Adv. Nonlinear Anal., 3 (2014), no. 4, 197-207, https://doi.org/10.1515/anona-2014-0006

## About this paper

##### Journal

Advances Nonlinear Analysis

##### Publisher Name

de Gruyter

##### Print ISSN

##### Online ISSN

2191-950X

google scholar link

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