Abstract
We construct division algebras with involution containing a Baer ordering with noninvariant order ring. This gives a negative answer to a question of Holland, whether the order ring is always invariant under inner automorphisms. Furthermore, we give examples of any index. Previously, the only known examples of division algebras containing Baer orderings were of index 2n or of indexp forp a prime of the form 4m + 3.
Similar content being viewed by others
References
M. Chacron,c-orderable division rings with involution, J. Algebra75 (1982), 495–522; correction, J. Algebra124 (1989), 230–235.
M. Chacron and A. Wadsworth,On decomposing c-valued division rings, J. Algebra, to appear.
T. Craven,Orderings and valuations on *-fields, Proceedings of the Corvallis Conference on Quadratic Forms and Real Algebraic Geometry, Rocky Mountain J. Math., to appear.
Yu. L. Ershov,Valued division rings, inFifth All Union Symposium, Theory of rings, Algebras, and Modules, Akad. Nauk SSSR Sibirsk. Otdel, Inst. Mat., Novosibirsk, 1982, pp. 53–55 (in Russian).
S. Holland,*-Valuations and ordered *-fields, Trans. Am. Math. Soc.262 (1980), 219–243.
S. Holland,Strong ordering of *-fields, J. Algebra101 (1986), 16–46.
S. Holland,Baer ordered *-fields of the first kind, Isr. J. Math.57 (1987), 365–374.
I. Idris,*-valuated division rings, orderings and elliptic Hermitian spaces, Ph.D. thesis, Carleton University, Ottawa, Canada, 1986.
B. Jacob and A. Wadsworth,A new construction of noncrossed product algebras, Trans. Am. Math. Soc.293 (1986), 693–721.
B. Jacob and A. Wadsworth,Division algebras over Henselian fields, J. Algebra, to appear.
T.-Y. Lam,Orderings, Valuations, and Quadratic Forms, CBMS Publ. No. 52, Am. Math. Soc., Providence, RI, 1983.
P. Morandi,The Henselization of a valued division algebra, J. Algebra122 (1989), 232–243.
V. P. Platonov and V. I. Yanchevskii,Dieudonné’s conjecture on the structure of unitary groups over a division ring, and Hermitian K-theory, Izv. Akad. Nauk SSSR, Ser. Mat.48 (1984), 1266–1294; (English transl.) Math. USSR Izv.25 (1985), 573–599.
A. Prestel,Lectures on Formally Real Fields, Lecture Notes in Math., Vol. 1093, Springer-Verlag, Berlin, Heidelberg, New York, Tokyo, 1984.
O. F. G. Schilling,The Theory of Valuations, Math. Surveys No. 4, Am. Math. Soc., Providence, RI, 1950.
J.-P. Tignol and A. Wadsworth,Totally ramified valuations on finite dimensional division algebras, Trans. Am. Math. Soc.302 (1987), 223–249.
A. Wadsworth,Extending valuations to finite dimensional division algebras, Proc. Am. Math. Soc.98 (1986), 20–22.
Author information
Authors and Affiliations
Additional information
Supported in part by the National Science Foundation.
Rights and permissions
About this article
Cite this article
Morandi, P.J., Wadsworth, A.R. Baer orderings with noninvariant valuation ring. Israel J. Math. 68, 241–255 (1989). https://doi.org/10.1007/BF02772663
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02772663