An extension of the notion of zero-epi maps to the context of topological spaces (Q699318)

The authors introduce the class of hyper-solvable equations whose concept may be regarded as an extension to the context of topological spaces of the known notion of 0-epi maps. After collecting some notation, definitions and preliminary results they give a homotopy principle for hyper-solvable equations. Moreover, they provide examples showing how these equations arise in the framework of Leray-Schauder degree, Lefschetz number theory and essential compact vector fields in the sense of A. Granas.