Spring 2007 New York Group Theory Seminar

Fridays at 4 p.m.

Department of Mathematics
CUNY, Graduate Center


365 Fifth Avenue at 34th Street, 5th Floor, Room 5417
Fridays at 4:00 p.m.
Tea served beforehand at 3:30 p.m. in Mathematics Lounge, 4th floor.


Jennifer Taback, Bowdoin College

Computing word length in alternate presentations of Thompson's group F

Much of the literature on Thompson's group F relies on the computations of word length with respect to the generating set {x0,x1} for this group. Fordham, Belk and Bux, and Guba and Sapir all discuss methods of computing this word length. Until now, there were no other sets of generators for F which allowed this exact computation of the word length of group elements.

I will present a new procedure for computing the word length of elements of F with respect to a set of "consecutive" generators of the form {x0, x1, ..., xn}. The three methods mentioned above for computing word length with respect to {x0, x1} are all special cases of this algorithm. Using this method, one can see that the group is not almost convex with respect to these generating sets, and has dead-end elements of depth dependent on n in these presentations.


Friday, February 23rd
Tea: 3:30 p.m. 4th Floor Mathematics Lounge
Seminar: 4 p.m. 5th Floor, Room 5417


The New York Group Theory Seminar and some of the associated conferences are supported by funds from the National Science Foundation, Dean of Science, Maria Tamargo and Dean of Engineering, Joe Barba.


Back to NYGTC