On formally real division algebras and quasifields of rank two

by Kalhoff, Franz

Abstract:
In view of Albert's classical result that the dimension of each ordered, associative proper algebra over its center is necessarily infinite, it seems not unlikely that a similar statement also holds for the rank of each proper formally real quasifield F, i.e. for the dimension of F over its kernel. Indeed, for some classes of ordered near fields and for ordered quasifields admitting a real kernel, D. Gröger and J. Joussen were able to verify that their rank must be one or infinite. However, making use of valuation theoretical means, recently (cf. preprint 96-05 ) we were able to show that for each natural number n formally real quasifields of rank n do exist. In this note we present a more elementary approach to a special case of the problem in question, namely to the existence of formally real quasifields and of formally real (unitary, necessarily not associative) division algebras of rank two.

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1991 Mathematics Subject Classification: Primary 06F25; Secondary 17A35.

Available as

Published in: Proceedings of the 4th International Congress of Geometry (Thessaloniki, 1996), 214--220, Giachoudis-Giapoulis, Thessaloniki, 1997.

Contact: Franz.Kalhoff@Mathematik.Uni-Dortmund.DE