Skip to main content
added 88 characters in body
Source Link
Shijie Gu
  • 2.1k
  • 1
  • 15
  • 18

This is a question about Hirshon's paper "The center and the commutator subgroup in hopfian groups"(https://projecteuclid.org/euclid.afm/1485894451). In Theorem 12, he showed stating that if $B$ is a perfect group with finitely many normal subgroups and $A$ is a hopfian group, then the direct product $A \times B$ is hopfian. Does $B$ haveIs it possible to be a group with finitelyweaken the "finitely many normal subgroupssubgroups" hypothesis?

This is a question about Hirshon's paper "The center and the commutator subgroup in hopfian groups". In Theorem 12, he showed that if $B$ is a perfect group and $A$ is a hopfian group, then the direct product $A \times B$ is hopfian. Does $B$ have to be a group with finitely many normal subgroups?

This is a question about Hirshon's paper "The center and the commutator subgroup in hopfian groups"(https://projecteuclid.org/euclid.afm/1485894451). Theorem 12 stating that if $B$ is a perfect group with finitely many normal subgroups and $A$ is a hopfian group, then the direct product $A \times B$ is hopfian. Is it possible to weaken the "finitely many normal subgroups" hypothesis?

Source Link
Shijie Gu
  • 2.1k
  • 1
  • 15
  • 18

Direct product of hopfian groups

This is a question about Hirshon's paper "The center and the commutator subgroup in hopfian groups". In Theorem 12, he showed that if $B$ is a perfect group and $A$ is a hopfian group, then the direct product $A \times B$ is hopfian. Does $B$ have to be a group with finitely many normal subgroups?