Critical Point Theory

“Many problems arizing in science and engineering call for the solving of nonlinear ordinary differential equations or partial differential equations. These equations are difficult to solve, and there are few general techniques … to solve them. … This has motivated researchers to study critical points of functionals in order to solve the corresponding Euler equations. It has led to the development of several techniques to find critical points. This book is dedicated to the latest developments and applications of these techniques.” (Mohsen Timoumi,zbMATH 1462.35008, 2021)

• Preface.- Linking Systems.- Sandwich Systems.- Linking Sandwich Sets.- The Monotonicity Trick.- Infinite Dimensional Linking.- Differential Equations.- Schrödinger Equations.- Zero in the Spectrum.- Global Solutions.- Second Order Hamiltonian Systems.- Core Functions.- Custom Monotonicity Methods.- Elliptic Systems.- Flows and Critical Points.- The Semilinear Wave Equation.- Nonlinear Optics.- Radially Symmetric Wave Equations.- Multiple Solutions.