Finite Dimensional Hopf Actions on Central Division Algebras

Let k be an algebraically closed field of characteristic zero. Let D be a division algebra of degree d over its center Z(D). Assume that k. Z(D). We show that a finite group G faithfully grades D if and only if G contains a normal abelian subgroup of index dividing d. We also prove that if a finite...

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Main Authors: Cuadra-Diaz, Juan, Etingof, Pavel I
Other Authors: Massachusetts Institute of Technology. Department of Mathematics
Format: Article
Published: Oxford University Press (OUP) 2018
Online Access:http://hdl.handle.net/1721.1/115878
https://orcid.org/0000-0002-0710-1416
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author Cuadra-Diaz, Juan
Etingof, Pavel I
author2 Massachusetts Institute of Technology. Department of Mathematics
author_facet Massachusetts Institute of Technology. Department of Mathematics
Cuadra-Diaz, Juan
Etingof, Pavel I
author_sort Cuadra-Diaz, Juan
collection MIT
description Let k be an algebraically closed field of characteristic zero. Let D be a division algebra of degree d over its center Z(D). Assume that k. Z(D). We show that a finite group G faithfully grades D if and only if G contains a normal abelian subgroup of index dividing d. We also prove that if a finite dimensional Hopf algebra coacts on D defining a Hopf-Galois extension, then its PI degree is at most d². Finally, we construct Hopf-Galois actions on division algebras of twisted group algebras attached to bijective cocycles.
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spelling mit-1721.1/1158782022-09-30T14:45:16Z Finite Dimensional Hopf Actions on Central Division Algebras Cuadra-Diaz, Juan Etingof, Pavel I Massachusetts Institute of Technology. Department of Mathematics Cuadra-Diaz, Juan Etingof, Pavel I Let k be an algebraically closed field of characteristic zero. Let D be a division algebra of degree d over its center Z(D). Assume that k. Z(D). We show that a finite group G faithfully grades D if and only if G contains a normal abelian subgroup of index dividing d. We also prove that if a finite dimensional Hopf algebra coacts on D defining a Hopf-Galois extension, then its PI degree is at most d². Finally, we construct Hopf-Galois actions on division algebras of twisted group algebras attached to bijective cocycles. 2018-05-24T20:10:37Z 2018-05-24T20:10:37Z 2016-05 2015-08 2018-05-21T14:38:29Z Article http://purl.org/eprint/type/JournalArticle 1073-7928 1687-0247 http://hdl.handle.net/1721.1/115878 Cuadra, Juan and Pavel Etingof. “Finite Dimensional Hopf Actions on Central Division Algebras.” International Mathematics Research Notices 5, 1 (May 2016): 1562–1577 © 2016 The Author(s) https://orcid.org/0000-0002-0710-1416 http://dx.doi.org/10.1093/IMRN/RNW030 International Mathematics Research Notices Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Oxford University Press (OUP) arXiv
spellingShingle Cuadra-Diaz, Juan
Etingof, Pavel I
Finite Dimensional Hopf Actions on Central Division Algebras
title Finite Dimensional Hopf Actions on Central Division Algebras
title_full Finite Dimensional Hopf Actions on Central Division Algebras
title_fullStr Finite Dimensional Hopf Actions on Central Division Algebras
title_full_unstemmed Finite Dimensional Hopf Actions on Central Division Algebras
title_short Finite Dimensional Hopf Actions on Central Division Algebras
title_sort finite dimensional hopf actions on central division algebras
url http://hdl.handle.net/1721.1/115878
https://orcid.org/0000-0002-0710-1416
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