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arXiv · 0705.3860

Indecomposable p-algebras and Galois subfields in generic abelian crossed products

Kelly McKinnie
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Abstract

Let F be a Henselian valued field with char(F) = p and D a semi-ramified, "not strongly degenerate" p-algebra. We show that all Galois subfields of D are inertial. Using this as a tool we study generic abelian crossed product p-algebras, proving among other things that the noncyclic generic abelian crossed product p-algebras defined by non-degenerate matrices are indecomposable p-algebras. To construct examples of these indecomposable p-algebras with exponent p and large index we study the relationship between degeneracy in matrices defining abelian crossed products and torsion in CH^2 of Severi-Brauer varieties.

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Kelly McKinnie. 2007-05-25. Indecomposable p-algebras and Galois subfields in generic abelian crossed products. https://arxiv.org/abs/0705.3860

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