F P M G
نویسنده
چکیده
In group theory, it is a fundamental question to determine what information about a group is necessary and sufficient tomake a group finitely presented. In this paper, we develop the theory of Σ-invariants due to Robert Bieri and Ralph Strebel [Bieri] whi provides an answer to this question for the class of metabelian groups. We begin our study of Σ-invariants with a digression on group extensions and basic definitions used throughout the paper. From there we define the Σ-invariants and establish their basic properties. We then devote a section to examples of computing the invariant ΣA. e computation of ΣA is difficult in general; mu work in the field is on developing methods to compute these invariants. In the last section, we sket the proof of the main theorem.
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تاریخ انتشار 2010