A Problem of Herstein on Group Rings
- 1 June 1974
- journal article
- Published by Canadian Mathematical Society in Canadian Mathematical Bulletin
- Vol. 17 (2) , 201-202
- https://doi.org/10.4153/cmb-1974-040-9
Abstract
Let F be a field of characteristic 0 and G a group such that each element of the group ring F[G] is either (right) invertible or a (left) zero divisor. Then G is locally finite.This answers a question of Herstein [1, p. 36] [2, p. 450] in the characteristic 0 case. The proof can be informally summarized as follows: Let gl,…,gn be a finite subset of G, and let 1—x is not a zero divisor so it is invertible and its inverse is 1+x+x3+⋯. The fact that this series converges to an element of F[G] (a finite sum) forces the subgroup generated by g1,…,gn to be finite, proving the theorem. The formal proof is via epsilontics and takes place inside of F[G].Keywords
This publication has 0 references indexed in Scilit: