Tuesday, October 23, 2018
Time  Items 

All day 

4:00pm 
10/23/2018  4:00pm In this work, we present a Deep Learning based approach for visual correspondence estimation, by deriving a Deep spectral graph matching network. We formulate the stateoftheart unsupervised Spectral Graph Matching (SGM) approach, as part of an endtoend supervised deep learning network. Thus allowing to utilize backpropagation to learn optimal image features, as well as algorithm parameters. For that, we present a transformation layer that converts the learned image feature, within a pair of images, to an affinity matrix used to solve the matching problem via a new metric loss function. The proposed scheme is shown to compare favorably with contemporary stateoftheart matching schemes when applied to annotated data obtained from the PASCAL, ILSVRC, KITTI and CUB2011 datasets. Location:
LOM 215
10/23/2018  4:00pm The rank of a group is the minimal cardinality of a generating set. While simple to define, this quantity is notoriously difficult to calculate, and often uncomputable, even for well behaved groups. In this talk I will explain general conditions that may be used to show many hyperbolic group extensions have rank equal to the rank of the kernel plus the rank of the quotient and, further, that any minimal generating set is Nielsen equivalent to one in a standard form. This builds on work of Souto on fundamental groups of fibered hyperbolic three manifolds and of ScottSwarup who in this setting proved that infiniteindex finitely generated subgroups of the fiber are quasiconvex in the ambient group. As an application, we prove that if $g_1,\dotsc,g_k$ are independent, atoroidal, fully irreducible outer automorphisms of the free group $F_n$, then there is a power $m$ so that the subgroup generated by $f_1^m,\dotsc,f_k^m$ gives rise to a hyperbolic extension of $F_n$ of rank $n+k$. Joint work with Sam Taylor. Location:
DL 431
10/23/2018  4:15pm We give another proof of the endoscopic fundamental lemma (theorem of LaumonNgo) for unitary Lie algebras in characteristic 0. We study the compatibility between Fourier transform and transfer and we prove that the compatibility in the JacquetRallis setting, after taking limits using germ expansions, will imply the compatibility in the endoscopic setting for unitary group. Location:
LOM 205
