Toronto

Mon 23 Jan 2017, 3:00pm
SPECIAL
Institute of Applied Mathematics
ESB 2012

Matrix regulation of stem cell fate

ESB 2012
Mon 23 Jan 2017, 3:00pm4:00pm
Abstract
Stem cell fate is regulated by cues from the cellular microenvironment, including biophysical and biochemical cues presented by the extracellular matrix. Matrix regulation of cell fate has broad implications from disease to regeneration. In this talk, I will discuss our work aimed at determining how biophysical and biochemical cues from the matrix act to drive the fate and function of mesenchymal stem cells. In particular, I will discuss how the pathological differentiation of heart valve progenitor cells is modulated by the extracellular matrix and how we are using microdevices to dissect how matrix mechanical and biochemical cues act in concert to regulate mesenchymal stem cell differentiation and tissue regeneration.
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Rennes / PIMS

Mon 23 Jan 2017, 3:00pm
Algebraic Geometry Seminar
MATX 1102

On Grothendieck rings in real geometry

MATX 1102
Mon 23 Jan 2017, 3:00pm4:00pm
Abstract
The study of Grothendieck rings of varieties in the context of real algebraic geometry has begun since the apparition of motivic integration. Several such rings are of interest, depending notably on the class of functions we are interested in. We will discuss recent progress in the cases of real algebraic varieties and of arcsymmetric sets.
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Max Planck Institute Bonn

Tue 24 Jan 2017, 3:00pm
SPECIAL
Diff. Geom, Math. Phys., PDE Seminar
MATH 126

Chiral differential operators and the curved betagamma system

MATH 126
Tue 24 Jan 2017, 3:00pm4:00pm
Abstract
Chiral differential operators (CDOs) are a vertex algebra analog of the associative algebra of differential operators. Originally introduced by mathematicians, Witten explained how CDOs arise as the perturbative part of the curved betagamma system with target X. I will describe recent work with Gorbounov and Williams in which we construct the BV quantization of this theory and use a combination of factorization algebras and formal geometry to recover CDOs. At the end, I hope to discuss how the techniques we developed apply to a broad class of nonlinear sigma models, including source manifolds of higher dimension.
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Center for Geometry and Physics/ Pohang Univ. of Sci. and Tech. Korea.

Tue 24 Jan 2017, 4:00pm
SPECIAL
MATH 1102 Topology/Algebra/Math Physics seminar

A quantization of the unipotent fundamental group

MATH 1102 Topology/Algebra/Math Physics seminar
Tue 24 Jan 2017, 4:00pm5:00pm
Details
We construct two homotopy functors from the category of homotopy commutative algebras to the category of prounipotent group and the category of completed commutative Hopf algebras such that
(1) the group is isomorphic to the pro unipotent fundamental group of smooth connected and based manifold (M,*) and
(2) the Hopf algebra is that of homotopy functionals defined by Chen’s iterated path integrals over closed and based loops on M
if the homotopy commutative algebra is quasiisomorphic to the algebra of differential forms on M.
These constructions can be quantized in appropriate sense after interpreting them as doing “classical field theory” such that the pro unipotent fundamental group is the structure in the space of all "classical expectations" and the completed Hopf algebra is the algebra of “classical observables”. The quantization involves a generalized deformation quantization of homotopy commutative algebra into topologically free homotopy associative algebra along the direction of compatible homotopy Lie algebra.
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UBC

Wed 25 Jan 2017, 1:45pm
Mathematical Biology Seminar
PIMS, ESB 4th floor

Multiscale modeling of vesicular release at neuronal synapses.

PIMS, ESB 4th floor
Wed 25 Jan 2017, 1:45pm2:45pm
Abstract
Binding of molecules, ions or proteins to small target sites is a generic step of cell activation. This process relies on rare stochastic events where a particle located in a large bulk has to find small and often hidden targets. I will present in this talk a hybrid discretecontinuum model that takes into account both a stochastic regime governed by rare events and a continuous regime in the bulk, in the context of vesicular release at chemical synapses.
In a first part, I computed the mean time for a Brownian particle to arrive at a narrow opening defined as the small cylinder joining two tangent spheres. This models the binding of calcium ions on the SNARE complex, a process that triggers vesicular release. Using this result, I developed a model to study how vesicles and calcium channels organization shape such process.
In a second part, I will present a model for the presynaptic terminal built using the results described above. This model was formulated in an initial stage as a reactiondiffusion problem in a confined microdomain, where Brownian particles have to bind to small target sites. I coarsegrained this model into a system of mass action equations coupled to a set of Markov equations, which allows to obtain analytical results and to realize fast stochastic simulations.
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Max Planck Institute Bonn

Wed 25 Jan 2017, 3:00pm
SPECIAL
Department Colloquium
ESB 2012 (note special day)

From Feynman diagrams to commutative diagrams

ESB 2012 (note special day)
Wed 25 Jan 2017, 3:00pm4:00pm
Abstract
Factorization algebras are localtoglobal objects that play a role in quantum field theory akin to the role of sheaves in geometry: they conveniently organize complicated information. In the talk I will introduce this notion, give some concrete examples, and then explain how factorization algebras mediate between QFT and higher algebra. An important example will be ChernSimons theory; ongoing work with Costello and Francis recovers quantum groups with formal parameter by combining Koszul duality with Feynman diagrams.
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University of Chicago

Wed 25 Jan 2017, 4:15pm
SPECIAL
Topology and related seminars
ESB 4133 (PIMS Lounge)

Quantitative Nullcobordism and the (in)effectiveness of algebraic topology.

ESB 4133 (PIMS Lounge)
Wed 25 Jan 2017, 4:15pm5:15pm
Abstract
Topology is full of ineffective arguments constructing objects and equivalences by algebra.
One of the great early achievements of algebraic topology was the work of Thom, followed by Milnor and Wall, on cobordism theory, which describes when a compact smooth (oriented) manifold is the boundary of some compact manifold with boundary. This method is typical of the problems that arise in the use of algebraic methods and is an early example of one of the dominant philosophies of geometric topology. The question we study is to what extent the complexity of a manifold can be used to bound, when it exists, the minimum necessary complexity of something that it bounds.
The goal of this talk is to explain generally some of the issues of making topology less ineffective.
We shall show that there are polynomial size nullcobordisms in a suitable sense. This is joint work with Greg Chambers, Dominic Dotterer and Fedor Manin.
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University of Texas at Austin

Thu 26 Jan 2017, 3:00pm
SPECIAL
Diff. Geom, Math. Phys., PDE Seminar
TBD

TBA

TBD
Thu 26 Jan 2017, 3:00pm4:00pm
Abstract
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University of Texas at Austin

Fri 27 Jan 2017, 3:00pm
Department Colloquium
ESB 2012

TBA

ESB 2012
Fri 27 Jan 2017, 3:00pm4:00pm
Abstract
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Institute for Theoretical Physics, KU Leuven

Mon 30 Jan 2017, 3:00pm
Department Colloquium
ESB 2012

Adiabatic Theory: From Spinning Top to Gapped Matter

ESB 2012
Mon 30 Jan 2017, 3:00pm4:00pm
Abstract
Adiabatic theory studies dynamical systems featuring separation of motion into slow and fast components. When the system is driven these components start mixing. The basic premise of adiabatic theory is that this mixing is small for slow driving. Furthermore, the resulting driven motion is irreversible in the slow component but reversible in the fast component. In this talk, I first illustrate this phenomena on a spinning top and state the classical adiabatic theorem of quantum mechanics. Then, I will show extensions of the theory to abstract Banach spaces and stochastic equations, culminating with an adiabatic theorem for extended systems where the separation holds uniformly in the volume of the system. An important corollary of this theorem is a proof of the Kubo formula for gapped interacting systems.
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Institute for Theoretical Physics, KU Leuven

Tue 31 Jan 2017, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
ESB 2012

On Products of Correlated Matrices Originating in the Statistical Structure of Quantum Mechanics

ESB 2012
Tue 31 Jan 2017, 3:30pm4:30pm
Abstract
Statistics of measurement outcomes in quantum mechanics is described by a map that associates a matrix to each possible measurement outcome. The probability of this outcome is then given by a trace of this matrix. Probability of a sequence of measurement outcomes is computed in the same way from a product of associated matrices. In this talk I will describe two results related to this setting. A theorem giving optimal conditions for uniqueness of the associated invariant measure on the projective sphere, and a theorem describing large deviation theory in the case when the matrices commute. The latter problem received lots of recent attention following experiments of S.~Haroche.
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University of Oregon

Wed 1 Feb 2017, 3:15pm
Topology and related seminars
ESB 4133 (PIMS Lounge)

TBA

ESB 4133 (PIMS Lounge)
Wed 1 Feb 2017, 3:15pm4:15pm
Abstract
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University of Munich

Thu 2 Feb 2017, 3:30pm
SPECIAL
Diff. Geom, Math. Phys., PDE Seminar
MATH 102 (note special day/room)

The adiabatic theorem for quantum spin systems

MATH 102 (note special day/room)
Thu 2 Feb 2017, 3:30pm4:30pm
Abstract
I will present an adiabatic theorem for the driven dynamics of ground state projections of a smooth family of manybody gapped quantum systems. The diabatic error is uniformly bounded in the volume of the interacting system. As an corollary, Kubo’s formula of linear response theory can be obtained in the thermodynamic limit.
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University of Munich

Fri 3 Feb 2017, 3:00pm
Department Colloquium
ESB 2012

What are ground state phases of matter?

ESB 2012
Fri 3 Feb 2017, 3:00pm4:00pm
Abstract
While thermal phases of matter (liquid water vs solid ice) are mathematically well understood, the theoretical understanding of ground state phases (at zero temperature) is incomplete. The discoveries of last year’s physics Nobel laureates provide a framework valid for noninteracting systems with topological properties, and I shall discuss current efforts to extend some of it to phases of strongly interacting matter.
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Technion

Mon 6 Feb 2017, 3:00pm
SPECIAL
Institute of Applied Mathematics
ESB 2012

Operator Representations for Geometry Processing

ESB 2012
Mon 6 Feb 2017, 3:00pm4:00pm
Abstract
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Wed 8 Feb 2017, 4:00pm
Discrete Math Seminar
ESB 4127

TBA

ESB 4127
Wed 8 Feb 2017, 4:00pm5:00pm
Abstract
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Kyoto University

Tue 14 Feb 2017, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
ESB 2012

TBA

ESB 2012
Tue 14 Feb 2017, 3:30pm4:30am
Abstract
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Kyoto University

Wed 15 Feb 2017, 3:00pm
Probability Seminar
ESB 2012

TBA

ESB 2012
Wed 15 Feb 2017, 3:00pm4:00pm
Abstract
TBA
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North Carolina State University

Wed 15 Feb 2017, 3:15pm
Topology and related seminars
ESB 4133 (PIMS Lounge)

Representation stability in configuration spaces via Whitney homology of the partition lattice

ESB 4133 (PIMS Lounge)
Wed 15 Feb 2017, 3:15pm4:15pm
Abstract
In recent years, important families of symmetric group representations have come to be better understood through the perspective of representation stability, a viewpoint introduced and developed by Thomas Church, Jordan Ellenberg, and Benson Farb, among others. A fundamental example of representation stability is the $S_n$module structure for the $i$th cohomology of the configuration space of $n$ distinct, labeled points in the plane, or more generally in a connected, orientable manifold, as $i$ is held fixed and $n$ grows. For the plane, this translates to Whitney homology of the partition lattice via an $S_n$equivariant version of the GoreskyMacPherson formula. This talk will survey the combinatorial literature regarding the partition lattice and discuss what new things this can tell us about representation stability for configuration spaces. In particular, we deduce new, sharp stability bounds and representation theoretic structure through a combination of symmetric function technology and poset topology. This is a joint work with Vic Reiner.
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Technion

Thu 16 Feb 2017, 3:30pm
Number Theory Seminar
ESB 4127

TBA

ESB 4127
Thu 16 Feb 2017, 3:30pm5:15am
Abstract
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U.C. Santa Barbara

Tue 21 Feb 2017, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
ESB 2012

TBA

ESB 2012
Tue 21 Feb 2017, 3:30pm4:30pm
Abstract
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University of California, San Diego

Fri 3 Mar 2017, 3:00pm
SPECIAL
Department Colloquium
ESB2012

PIMSUBC Distinguished ColloquiumTBA

ESB2012
Fri 3 Mar 2017, 3:00pm4:00pm
Abstract
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University of Grenoble

Fri 10 Mar 2017, 3:00pm
SPECIAL
Department Colloquium
ESB 2012

PIMSUBC Distinguished ColloquiumTBA

ESB 2012
Fri 10 Mar 2017, 3:00pm4:00pm
Abstract
PIMSUBC Distinguished Colloquium TBA
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University of Grenoble

Mon 13 Mar 2017, 3:00pm
Algebraic Geometry Seminar
MATH 126

TBA

MATH 126
Mon 13 Mar 2017, 3:00pm4:00pm
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MIT

Mon 13 Mar 2017, 3:00pm
SPECIAL
Institute of Applied Mathematics
ESB 2012

Multifidelity and Surrogate Modeling for 'Data to Decisions' in Engineering Systems

ESB 2012
Mon 13 Mar 2017, 3:00pm4:00pm
Abstract
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UBC Math

Fri 17 Mar 2017, 3:00pm
Department Colloquium

Graduate Research Award  TBA

Fri 17 Mar 2017, 3:00pm4:00pm
Abstract
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Caltech

Wed 22 Mar 2017, 3:00pm
SPECIAL
Department Colloquium
ESB 2012

Public Lecture  TBA

ESB 2012
Wed 22 Mar 2017, 3:00pm4:00pm
Abstract
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Caltech

Thu 23 Mar 2017, 3:30pm
SPECIAL
Department Colloquium
ESB 2012

PIMSUBC Distinguished Colloquium  TBA

ESB 2012
Thu 23 Mar 2017, 3:30pm4:30pm
Abstract
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UBC Math

Fri 24 Mar 2017, 3:00pm
Department Colloquium

Graduate Research Award  TBA

Fri 24 Mar 2017, 3:00pm4:00pm
Abstract
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UBC Math

Fri 31 Mar 2017, 3:00pm
Department Colloquium

Graduate Research Award  TBA

Fri 31 Mar 2017, 3:00pm4:00pm
Abstract
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Utah

Mon 3 Apr 2017, 3:00pm
SPECIAL
Institute of Applied Mathematics
ESB 2012

Extending the Theory of Composites to Other Areas of Science

ESB 2012
Mon 3 Apr 2017, 3:00pm4:00pm
Abstract
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SNS, Pisa

Fri 2 Mar 2018, 3:00pm
SPECIAL
Department Colloquium
ESB2012

PIMSUBC Distinguished ColloquiumTBA

ESB2012
Fri 2 Mar 2018, 3:00pm4:00pm
Abstract
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Note for Attendees
Reception preceding the talk in ESB 4133 (the PIMS lounge). This is part of the IAM/PIMS distinguished colloquium series.