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	Selected talks
	Fractional Distortion in Hyperbolic Groups, (pdf) Bob Gilman's 80th Birthday Conference, Stevens Institute, 2023 Conjugator Length, (pdf) 2020 Screwball Conjectures, (pdf) 2019 Dehn functions, the word problem, hydra, and magical salmon, (pdf, 7.4MB) GAGTA, 2016 Hyperbolic groups, Cannon-Thurston Maps, and hydra, (Quicktime Movie, 35.7MB) Warwick Colloquium, 2014 Lamplighters, metabelian groups, and horocyclic products, (Quicktime Movie, 18.7MB) GAGTA, CCNY, 2013 Big numbers, graph coloring, and Hercules' battle with the hydra, (pdf, 13.9MB) K–12 Education and Outreach, Cornell, 2011 The Dehn function of Baumslag's metabelian group, (pdf, 3.9MB) Binghamtom, Geometry & Topology Seminar, 2011 Hydra Groups, (pdf, 10.3MB) What is a Dehn function? (pdf, 6.3MB) "What is..." Seminar, Cornell 2009 What is amenability? (pdf, 2.1MB) Introductory talk, Bristol–Oxford–Southampton Network in Geometric and Analytic Methods in Group Theory, 2009 How wild can a group with quadratic Dehn function be? (pdf, 19.9MB) Workshop on Boundaries, Graz, June 2009 The Geometry of the Conjugacy Problem, (pdf, 10.47MB) Survey Talk, Ottawa, December 2007 Outstanding Problems in Low-Dimensional Topology and Group Theory, (pdf, 18MB) Survey Talk, Ottawa, December 2007 Missing photos welcome! An earlier version of this talk was given at the 2007 Cornell Topology Festival. The geometry of discs spanning loops in groups and spaces, (pdf, 25.7MB) Cornell Topology Festival, May 2007 Geometric notions of space complexity for the word problem, (pdf, 225KB) Combinatorial and Geometric Group Theory, Vanderbilt, May 2006 Intrinsic versus extrinsic diameter in finitely presented groups, (pdf, 268KB) Asymptotic and Probabilistic Methods in Geometric Group Theory, Geneva, June 2005 Diameters of Cayley graphs of SL_n(Z/kZ), (pdf, 136KB) Geometric Group Theory, Barcelona, June 2005 Navigating in the Cayley graphs of SL_N(Z) and SL_N(F_p), (pdf, 59KB) Albany Group Theory Conference, October 2004

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