Nonlinear analysis and variational problems – in honour of George Isac

In the papers published in this volume, outstanding mathematicians discuss the present state and the broad spectrum of topics in nonlinear analysis and variational problems. The volume is dedicated to the memory of the eminent mathematician George Isac, who past away in February 2009 at the age of 69. The papers focus on a number of recent developments in complementarity theory, variational principles, stability theory of functional equations, non-smooth optimization and several other important topics of nonlinear analysis and optimization. The underlying methodological principle is to develop a unified approach to various kinds of problems and theories in nonlinear mathematics, and the contributing authors deal primarily with interaction among problems of analysis and geometry in the context of optimization, nonlinearity, variational calculus and stability. The methods employed are accessible to graduate students familiar with basic mathematical analysis, geometry and topology. The theorems, solutions, and applications presented in the volume are simple and challenging. Topics dealt with in this volume include: discrete approximation processes, isometries in nonArchimedean strictly convex spaces, fixed point theory and functional stability of mappings, stability and asymptotic behaviour of quadratic mappings, stability of the logarithmic functional equation, Grownwall lemma, integral equations, Brezis–Browder principles, generalized quasi-equilibrium problems, special types of dynamical systems, nonlinear generalized ordered complementarity problems, optimality conditions, vector-valued Ekeland-type variational principle, linear/quadratic Lyapunov functions, nonlinear problems in mathematical programming and optimal control, generating eigenvalue bounds using optimization and other related topics. This volume provides a great service to both pure and applied mathematics by presenting important foundational material in a clear and self-contained form. It will be a valuable resource for graduate students and researchers who work in nonlinear analysis and variational problems.