An Overview of Baer's Theorem and Its Extensions

Document Type : Research Paper

Author

Department of Pure Mathematics, Ferdowsi University of Mashhad, P. O. Box 1159-91775, Mashhad, Iran

Abstract

Baer's theorem is one of the cornerstone result in group theory, providing critical insights into the relationship between the finiteness of central factor group and that of the commutator subgroup. Building upon Schur's foundational work, Baer's theorem connects the upper and lower central series, establishing constraints on group structure that have far-reaching implications. This paper provides a brief review of Baer's theorem, detailing its historical development, generalizations, and recent extensions. Some key results include exponents, bounds on central series, extensions to locally generalized radical groups, finite rank conditions and applications to automorphism-influenced properties are given. Invoking the notion of variety of groups, we also propound the Baer's (or Schur's) theorem in its most general form as a fundamental question and attempt to identify all classes of groups that are Schur-Baer with respect to some variety as potential answers. Particular attention is also given to some of its applications in diverse areas of mathematics. Furthermore, the paper explores open problems and potential research directions, underscoring the theorem's enduring significance and its role in shaping contemporary mathematical inquiry.

Keywords

Main Subjects


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Articles in Press, Corrected Proof
Available Online from 15 April 2025
  • Receive Date: 24 February 2025
  • Revise Date: 13 April 2025
  • Accept Date: 18 March 2025
  • Published Online: 15 April 2025