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arXiv · 1703.02356

Automorphisms and isomorphisms of Jha-Johnson semifields obtained from skew polynomial rings

Christian Brown·Susanne Pumpluen·Andrew Steele
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Abstract

We study the automorphisms of Jha-Johnson semifields obtained from an invariant irreducible twisted polynomial $f\in K[t;\sigma]$, where $K=\mathbb{F}_{q^n}$ is a finite field and $\sigma$ an automorphism of $K$ of order $n$, with a particualr emphasis on inner automorphisms and the automorphisms of Sandler and Hughes-Kleinfeld semifields. We include the automorphisms of some Knuth semifields (which do not arise from skew polynomial rings). Isomorphism between Jha-Johnson semifields are considered as well.

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Christian Brown, Susanne Pumpluen, Andrew Steele. 2017-03-07. Automorphisms and isomorphisms of Jha-Johnson semifields obtained from skew polynomial rings. https://doi.org/10.1080/00927872.2018.1448845

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