SPECIAL LECTURE | |

Topic: | Infinite Generaton of Non-Cocompact Lattices on Right-Angled Buildings |

Speaker: | Anne Thomas |

Affiliation: | University of Sydney, NSW |

Date: | Wednesday, April 6 |

Time/Room: | 4:00pm - 5:00pm/S-101 |

Video Link: | https://video.ias.edu/special-lecture/thomas |

Let Gamma be a non-cocompact lattice on a right-angled building X. Examples of such X include products of trees, or Bourdon's building I_{p,q}, which has apartments hyperbolic planes tesselated by right-angled p-gons and all vertex links the complete bipartite graph K_{q,q}. We prove that if Gamma has a strict fundamental domain then Gamma is not finitely generated. The proof uses a topological criterion for finite generation and the separation properties of subcomplexes of X called tree-walls. This is joint work with Kevin Wortman (Utah).