The Geometry of 1-cusped and 2-cusped Picard Modular Groups
Description
Mark and Paupert concocted a general method for producing presentations for arithmetic non-cocompact lattices, \(\Gamma\), in isometry groups of negatively curved symmetric spaces. To get around the difficulty of constructing fundamental domains in spaces of variable curvature, their method invokes a classical theorem of Macbeath applied to a \(\Gamma\)-invariant covering by horoballs of the negatively curved symmetric space upon which \(\Gamma\) acts. This thesis aims to explore the application of their method to the Picard modular groups, PU\((2,1;\mathcal{O}_{d})\), acting on \(\mathbb{H}_{\C}^2\). This document contains the derivations for the group presentations corresponding to \(d=2,11\), which completes the list of presentations for Picard modular groups whose entries lie in Euclidean domains, namely those with \(d=1,2,3,7,11\). There are differences in the method's application when the lattice of interest has multiple cusps. \(d = 5\) is the smallest value of \(d\) for which the corresponding Picard modular group, \(\PU(2,1;\mathcal{O}_5)\), has multiple cusps, and the method variations become apparent when working in this case.
Date Created
The date the item was original created (prior to any relationship with the ASU Digital Repositories.)
2021
Agent
- Author (aut): Polletta, David Michael
- Thesis advisor (ths): Paupert, Julien H
- Committee member: Kotschwar, Brett
- Committee member: Fishel, Susanna
- Committee member: Kawski, Matthias
- Committee member: Childress, Nancy
- Publisher (pbl): Arizona State University