Two-dimensional submanifolds in non-simply connected 4-manifolds

摘要

A foundamental problem in 4-dimensional differential topology is to find a surface with minimal genus that can represent a given two-dimensional homology class. Hsiang, Rohlin have got some results about the homological 1-connected manifolds. This note will discuss this problem under the condition that H_1(N~4) is finite Under this assumption, the possible normal Euler numbers of embedding nonorientable surfaces in 4-manifolds are also determined.