Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-26T13:07:57.612Z Has data issue: false hasContentIssue false

ON REGULAR GROUPS AND FIELDS

Published online by Cambridge University Press:  18 August 2014

TOMASZ GOGACZ
Affiliation:
INSTYTUT INFORMATYKI, UNIWERSYTET WROCŁAWSKI, UL. JOLIOT-CURIE 15, 50-383 WROCŁAW, POLANDE-mail: gogo@cs.uni.wroc.pl
KRZYSZTOF KRUPIŃSKI
Affiliation:
INSTYTUT MATEMATYCZNY, UNIWERSYTET WROCŁAWSKI, PL. GRUNWALDZKI 2/4, 50-384 WROCŁAW, POLANDE-mail: kkrup@math.uni.wroc.pl

Abstract

Regular groups and fields are common generalizations of minimal and quasi-minimal groups and fields, so the conjectures that minimal or quasi-minimal fields are algebraically closed have their common generalization to the conjecture that each regular field is algebraically closed. Standard arguments show that a generically stable regular field is algebraically closed. Let K be a regular field which is not generically stable and let p be its global generic type. We observe that if K has a finite extension L of degree n, then P(n) has unbounded orbit under the action of the multiplicative group of L.

Known to be true in the minimal context, it remains wide open whether regular, or even quasi-minimal, groups are abelian. We show that if it is not the case, then there is a counter-example with a unique nontrivial conjugacy class, and we notice that a classical group with one nontrivial conjugacy class is not quasi-minimal, because the centralizers of all elements are uncountable. Then, we construct a group of cardinality ω1 with only one nontrivial conjugacy class and such that the centralizers of all nontrivial elements are countable.

Type
Articles
Copyright
Copyright © The Association for Symbolic Logic 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Adler, H., Introduction to theories without the independence property. Archive for Mathematical Logic, to appear.Google Scholar
Hrushovski, E., Peterzil, Y., and Pillay, A., Groups, measures and the NIP. Journal of AMS, vol. 21 (2008), pp. 563596.Google Scholar
Hyttinen, T., Lessmann, O., and Shelah, S., Interpreting groups and fields in some nonelementary classes. Journal of Mathematical Logic, vol. 5 (2005), pp. 147.Google Scholar
Krupiński, K., Fields interpretable in rosy theories. Israel Journal of Mathematics, vol. 175 (2010), pp. 421444.Google Scholar
Krupiński, K., On ω-categorical groups and rings with NIP. Proceedings of AMS, vol. 140 (2012), pp. 25012512.Google Scholar
Krupiński, K., Tanović, P., and Wagner, F., Around Podewski’s conjecture. Fundamenta Mathematicae, vol. 222 (2013), pp. 175193.Google Scholar
Lyndon, R. C. and Schupp, P. E., Combinatorial group theory, Springer, Germany, 1977.Google Scholar
Pillay, A. and Tanović, P., Generic stability, regularity, and quasiminimality, Models, Logics and Higher-Dimensional Categories (A Tribute to the Work of Mihály Makkai), CRM Proceedings and Lecture Notes, vol. 53, 2011, pp. 189211.CrossRefGoogle Scholar
Reineke, J., Minimale gruppen. Zeitschrift fur Mathematische Logik und Grundlagen derMathematik, vol. 21 (1975), pp. 357359.Google Scholar
Wagner, F. O., Minimal fields, this Journal, vol. 65 (2000), pp. 18331835.Google Scholar
Zilber, B., Pseudo-exponentiation on algebraically closed fields of characteristic zero. Annals of Pure and Applied Logic, vol. 132 (2005), pp. 6795.Google Scholar