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Proceedings of the American Mathematical Society
Proceedings of the American Mathematical Society
ISSN 1088-6826 (e) ISSN 0002-9939 (p)
     

All dihedral division algebras of degree five are cyclic

Author(s): Eliyahu Matzri
Journal: Proc. Amer. Math. Soc. 136 (2008), 1925-1931.
MSC (2000): Primary 16K20, 12E15
Posted: February 7, 2008
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Abstract: In 1982 Rowen and Saltman proved that every division algebra which is split by a dihedral extension of degree $ 2n$ of the center, $ n$ odd, is in fact cyclic. The proof requires roots of unity of order $ n$ in the center. We show that for $ n=5$, this assumption can be removed. It then follows that $ {}_{5\:}\operatorname{Br}(F)$, the $ 5$-torsion part of the Brauer group, is generated by cyclic algebras, generalizing a result of Merkurjev (1983) on the $ 2$ and $ 3$ torsion parts.


References:

1.
A.A. Albert, Structure of Algebras, Amer. Math. Soc. Colloq. Publ., Vol. XXIV, 1961. MR 0123587 (23:A912)

2.
D. F. Coray, Algebraic points on cubic hypersurfaces, Acta Arithmetica 30 (1976), 267-296. MR 0429731 (55:2742)

3.
D. Haile, A useful proposition for division algebras of small degree, Proceedings of the American Mathematical Society 106 (1989), 317-319. MR 972232 (89k:16037)

4.
D. Haile, M. A. Knus, M. Rost, J. P. Tignol, Algebras of odd degree with involution, trace forms and dihedral extensions, Israel J. Math. 96 B (1996), 299-340 - Amitsur Volume. MR 1433693 (98h:16024)

5.
N. Jacobson, Finite-Dimensional Division Algebras over Fields, Springer-Verlag, 1996. MR 1439248 (98a:16024)

6.
P. Mammone and J. P. Tignol, Dihedral algebras are cyclic, Proceedings of the American Mathematical Society 101 (1987), 217-218. MR 902530 (89b:12005)

7.
A. S. Merkurjev, Brauer groups of fields, Comm. Algebra 11(22) (1983), 2611-2624. MR 733345 (85f:12006)

8.
L. H. Rowen, Ring theory, Pure and Applied Mathematics, Academic Press, Boston, MA, 1991 (student edition). MR 1095047 (94e:16001)

9.
L. H. Rowen and David J. Saltman, Dihedral algebras are cyclic, Proceedings of the American Mathematical Society 84 (1982), 162-164. MR 637160 (83c:16013)

10.
U. Vishne, Galois cohomology of fields without roots of unity, Journal of Algebra 279(2) (2004), 451-492. MR 2078127 (2005e:12008)


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Additional Information:

Eliyahu Matzri
Affiliation: Department of Mathematics, Bar-Ilan University, Ramat-Gan, 52900, Israel
Email: elimatzri@gmail.com

DOI: 10.1090/S0002-9939-08-09310-6
PII: S 0002-9939(08)09310-6
Keywords: Central simple algebras, cyclic algebras
Received by editor(s): November 27, 2006
Posted: February 7, 2008
Additional Notes: The author thanks his supervisors, L. H. Rowen and U. Vishne, for many interesting and motivating talks and for supporting this work through BSF grant no. 2004-083.
Communicated by: Martin Lorenz
Copyright of article: Copyright 2008, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.


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