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arXiv · 1402.0328

$\mathbb{Z}_3\times \mathbb{Z}_3$ crossed products

Eliyahu Matzri
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Abstract

Let $A$ be the generic abelian crossed product with respect to $\mathbb{Z}_3\times \mathbb{Z}_3$, in this note we show that $A$ is similar to the tensor product of 4 symbol algebras (3 of degree 9 and one of degree 3) and if $A$ is of exponent $3$ it is similar to the product of 31 symbol algebras of degree $3$. We then use \cite{RS} to prove that if $A$ is any algebra of degree $9$ then $A$ is similar to the product of $35840$ symbol algebras ($8960$ of degree $3$ and $26880$ of degree $9$) and if $A$ is of exponent $3$ it is similar to the product of $277760$ symbol algebras of degree $3$. We then show that the essential $3$-dimension of the class of $A$ is at most $6$.

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Eliyahu Matzri. 2014-02-03. $\mathbb{Z}_3\times \mathbb{Z}_3$ crossed products. https://arxiv.org/abs/1402.0328

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