Revisiting Markus–Neumann theorem
摘要
Up to topological equivalence, a continuous flow in a surface is determined by its separatrix configuration. This claim is widely known as Markus–Neumann theorem, but it is false with the definition of separatrix originally considered. Recently, Espín Buendía and Jiménez López delivered counterexamples and proposed an updated definition of separatrix in order that the claim becomes true. The main objective of this paper is to provide a detailed and self-contained proof of Markus–Neumann theorem taking into account this new definition of separatrices, with a slight generalization.