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Current contact: Dave Futer or Matthew Stover
The Seminar usually takes place on Wednesdays at 2:45 PM in Room 617 on the sixth floor of Wachman Hall.
Chris Atkinson, Temple University, A combinatorial lower bound on the volume of hyperbolic Coxeter polyhedra
Will Cavendish, Princeton University, On the growth rate of the Weil-Petersson diameter of moduli space
Ara Basmajian, CUNY, Length bounds for self-intersecting geodesics
Moon Duchin, University of Michigan, Measuring the failure of hyperbolicity
Shawn Rafalski, Fairfield University, Small hyperbolic polyhedra
Joseph Maher, CUNY, Generic elements of the mapping class group
Ken Shackleton, University of Tokyo, On the coarse geometry of Teichmuller space
Louis Theran, Temple University, Parallel redrawing, rigidity, and slider-pinning
Ian Biringer, Yale University, Geometric consequences of algebraic rank in hyperbolic 3-manifolds
Karin Melnick, University of Maryland, Normal forms for conformal vector fields
PATCH seminar, joint with Bryn Mawr & Haverford
John Baldwin, Princeton University, Contact monoids and Stein cobordisms
PATCH seminar, joint with Bryn Mawr & Haverford
Josh Sabloff, Haverford College, Lagrangian caps for Legendrian knots via generating families
John Humphrey, EM Photonics, Using GPUs to Improve Numerical Calculations
GPUs have been a topic of intense research for accelerating numerical processing, due to their high FLOPS/dollar and FLOPS/watt ratios. In particular, the field of numerical linear algebra has been a field of high payoff due to the applicability of the GPU and the widely useful nature of calculations such a system solutions and eigenproblem analysis. We will discuss our experience in this area in light of our CULA package for GPU accelerated linear algebra operations, which Temple University has leveraged in the creation of their PyCULA package.
Walter Whiteley, York University, When does added symmetry shifts rigid structures to flexible structures?
For finite frameworks with graph $G$ in dimensions $2$ and $3$, we have necessary conditions for rigidity; $|E| = 2|V|-3$ in the plane (Laman's Theorem) and $|E|=3|V|-6$ in 3-space (Maxwell's condition). Recently, work by a group of researchers has given modified necessary counts for orbits of finite symmetric frameworks, whose failure guarantees symmetry generic frameworks are flexible. The most striking case, visible in a number of classical examples, is generically isostatic frameworks in 3-space which become flexible with half-turn symmetry.
Several recent papers have given necessary (and sometimes sufficient) conditions for periodic generic frameworks to be infinitesimally rigid. Building on these two foundations, recent work with Bernd Schulze (TU Berlin) and Elissa Ross (York University) has examined necessary conditions for rigidity of periodic frameworks with added symmetry. Again, there are circumstances, such as inversive symmetry in a crystal which convert the count for generic rigidity into an orbit count which guarantees flexibility.
We will present an overview of these results, with a few animations and tables, as well as the core technique of orbit rigidity matrices. We conclude with an array of unsolved problems. Related papers are on the arXiv.
Radmila Sazdanović, University of Pennsylvania, Categorification of knot and graph polynomials
We review homology theories of links and graphs, focusing on Khovanov link and chromatic graph homology and relations between them.
Fred Cohen, University of Rochester, Spaces of particles, their applications and connections.
This talk is an exposition of topological, and geometric properties of the classical configuration space of distinct particles in a manifold.
The main setting is how features of these spaces 'connect' to several phenomena such as linking of circles in three dimensions, knots in three dimensions as well as homotopy groups of spheres. Explanations will be given for how and why these structures fit together.
2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023