Group homomorphisms inducing cohomology monomorphisms
Authors:
Pham Anh Minh
Affiliation:
Department of Mathematics, Faculty of Science, University of Hue, Dai hoc Khoa hoc, Hue, Vietnam
Abstract:
Let be a homomorphism of -groups such that is injective, for . We prove that the non-bijectivity of implies the existence of a quotient of containing as a proper direct factor. This gives a refined proof of a result of Evens, which asserts that is bijective if is.