A new approach to character-free proof for Frobenius theorem

Document Type : Original Article

Authors

1 Department of Mathematics, Stony Brook University, Stony Brook, New York, USA

2 Department of Mathematics, KTH Royal Institute of Technology, Stockholm, Sweden

Abstract

Let G be a Frobenius group. Using character theory, it is proved that the Frobenius kernel of G is a normal subgroup of G, which is well-known as a Frobenius theorem. There is no known character-free proof for Frobenius theorem. In this note, we prove it, by assuming that Frobenius groups are non-simple. Also, we prove that whether K is a subgroup of G or not, Sylow 2-subgroups of G are either cyclic or generalized quaternion group. Also by assuming some additional arithmetical hypothesis on G we prove Frobenius theorem. We should mention that our proof is character-free.

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