a hopfian object is an object A such that any epimorphism of A onto A is necessarily an automorphism. The dual notion is that of a cohopfian object, which...
6 KB (842 words) - 10:38, 15 April 2024
group theory, a co-Hopfian group is a group that is not isomorphic to any of its proper subgroups. The notion is dual to that of a Hopfian group, named after...
10 KB (1,533 words) - 22:52, 3 May 2024
the field of pure mathematics. Co-Hopfian group Cohomotopy group EHP spectral sequence Hopfian group Hopfian object Quantum group Alexandroff P., Hopf...
11 KB (970 words) - 05:12, 25 July 2024
automorphism of M. This says simply that M is a Hopfian module. Similarly, an Artinian module M is coHopfian: any injective endomorphism f is also a surjective...
19 KB (2,837 words) - 22:51, 25 November 2023