Walter Neumann

Professor of Mathematics, Barnard College, Columbia University.

Teaching Fall 2016

Math GU4051: Topology, MW 1:10-2:25, Room 520 Math
Math G6307: Algebraic Topology I, MW 2:40-3:55, Room 520


Some of my (P)REPRINTS are linked here.

Software for computing arithmetic invariants of 3-manifolds: Snap is a computer program for computing arithmetic invariants of hyperbolic 3-manifolds, written by Oliver Goodman as part of an ARC-funded project of Craig Hodgson and Walter Neumann. It is based in part on Jeff Weeks' program Snappea. One nice feature of the latest version is: if you have an unknown manifold, snap will identify it for you (if it is in the census or is the complement of a knot with at most 16 crossings). Snap is now hosted at Sourceforge. The latest release of snap can always be downloaded from there: The original home page for snap at has some additional information and software.