On a new notion of linking and application to elliptic problems at resonance (Q1284429)

In critical point theory the notion of linking is very important. There are many various definitions of linking (homotopical, homological, local, linking in the sense of Benci-Rabinowitz). The author introduces a new notion of linking which includes in particular the notions of homotopical linking and local linking. He presents also minimax critical point theorems and obtains as particular cases generalizations of many results such as the moutain pass theorem, saddle point theorem, minimax theorem. Also an application to nonlinear elliptic boundary value problems at resonance is presented.