The symmetry of intersection numbers in group theory

For suitable subgroups of a finitely generated group, we define the intersection number of one subgroup with another subgroup and show that this number is symmetric. We also give an interpretation of this number.

Keywords

ends, amalgamated free products, trees

Mathematical Subject Classification

Primary: 20F32

Secondary: 20E06, 20E07, 20E08, 57M07

References

Forward citations

Publication

Received: 21 February 1997

Revised: 13 March 1998

Accepted: 19 March 1998

Published: 19 March 1998

Proposed: Jean-Pierre Otal

Seconded: Cameron Gordon, Walter Neumann

Authors

Peter Scott
Mathematics Department University of Michigan Ann Arbor Michigan 48109 USA

Volume 2, issue 1 (1998)

Peter Scott