Files in this item



application/pdf9124411.pdf (4MB)Restricted to U of Illinois
(no description provided)PDF


Title:The Hanna Neumann conjecture: A flow detection approach
Author(s):Feuerman, Kenneth Edward
Department / Program:Mathematics
Degree Granting Institution:University of Illinois at Urbana-Champaign
Abstract:The Hanna Neumann Conjecture states that if two subgroups of a finitely generated free group have finite ranks m and n, then their intersection has rank N which satisfies $N$ $-$ 1 $\leq$ ($m$ $-$ 1)($n$ $-$ 1). The current work examines this conjecture by restating it in terms of a stronger conjecture on the pullback in a particular category of graphs. The notion of a vertex pairing is developed, and shown to have a direct bearing on the pullback conjecture. In this light, the Flow Conjecture is stated, and its relationship as an apparently stronger conjecture than the Hanna Neumann Conjecture becomes evident. We then prove the Flow Conjecture for certain special cases by detecting a special kind of "short" flow. Finally, we examine the properties of projection and non-projection flows that are intended to lead to a full solution to the Hanna Neumann Conjecture.
Issue Date:1991
Rights Information:Copyright 1991 Feuerman, Kenneth Edward
Date Available in IDEALS:2011-05-07
Identifier in Online Catalog:AAI9124411
OCLC Identifier:(UMI)AAI9124411

This item appears in the following Collection(s)

Item Statistics