A separable deformation of the quaternion group algebra

Barnea, Nurit; Ginosar, Yuval

doi:10.1090/S0002-9939-08-09480-X

A separable deformation of the quaternion group algebra
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by Nurit Barnea and Yuval Ginosar PDF

Proc. Amer. Math. Soc. 136 (2008), 2675-2681 Request permission

Abstract:

The Donald-Flanigan conjecture asserts that for any finite group $G$ and any field $k$, the group algebra $kG$ can be deformed to a separable algebra. The minimal unsolved instance, namely the quaternion group $Q_8$ over a field $k$ of characteristic 2 was considered as a counterexample. We present here a separable deformation of $kQ_8$. In a sense, the conjecture for any finite group is open again.

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