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arXiv · 1406.6771

Free subgroups in group rings

Victor Bovdi
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Abstract

Let V(KG) be the normalized group of units of the group ring KG of a non-Dedekind group G with nontrivial torsion part t(G) over the integral domain K. We give a simple method for constructing free objects in V(KG).In particular, we show that V(KG) always contains the free product C_n*C_n of two finite cyclic groups. We construct examples of subgroups in V(KG), which are either cyclic extensions of a non-abelian free group or C_n*C_n.

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Victor Bovdi. 2014-06-26. Free subgroups in group rings. https://arxiv.org/abs/1406.6771

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