Seminars Sorted by Series

Workshop on Thin Groups and Super Approximation

Workshop on Topology: Identifying Order in Complex Systems

Feb
04
2009

Workshop on Topology: Identifying Order in Complex Systems

Homology and Data Samples
Shmuel Weinberger
2:00pm|S-101

In this talk, I will try to explain some of the interest in the question of the computation of the homology of a space from noisy data samples as it relates to clustering and other natural problems. Moreover, I will also try to indicate some...

Apr
01
2009

Workshop on Topology: Identifying Order in Complex Systems

Stimulus Space Topology and Geometry from Neural Activity
Carina Curto
5:00pm|S-101

We construct our understanding of the world solely from neuronal activity generated in our brains. How do we do this? Many studies have investigated how the electrical activity of neurons (action potentials) is related to outside stimuli, and maps...

Nov
04
2009

Workshop on Topology: Identifying Order in Complex Systems

Computational Topology in the Study of Discrete Dynamical Systems
Sarah Day
3:30pm|S-101

With recent advances in computing power, numerical studies of nonlinear dynamical systems have become increasingly more popular. However, errors inherent to such studies may obscure the dynamics, or in the very least raise doubts about the existence...

Dec
02
2009

Workshop on Topology: Identifying Order in Complex Systems

Electrical and Systems Engineering
Daniel Koditschek
2:00pm|Hill Center, Rutgers, The State University of New Jersey (CoRe 433)

My collaborators and I have spent a the better part of two decades seeking to develop formally and apply empirically methods of programming work: that is, we want to know how to say what we mean, yet mean what we say to a machine built for...

Dec
02
2009

Workshop on Topology: Identifying Order in Complex Systems

Knots in Proteins
Alexander Grosberg
3:30pm|Hill Center, Rutgers, The State University of New Jersey (CoRe 433)

Proteins with knots in their native state were discovered few years ago. Analysis of the entire protein data base indicates that there are quite a few proteins with knots, particularly with slip knots, but still the fraction of proteins with knots...

Dec
02
2009

Workshop on Topology: Identifying Order in Complex Systems

Topological Methods in the Arnold Diffusion Problem
5:00pm|Hill Center, Rutgers, The State University of New Jersey (CoRe 433)

We discuss some geometric and topological methods that are applied to overcome the large gap problem in Arnold diffusion for a priori unstable Hamiltonian systems. The geometric methods rely on the theory of normally hyperbolic invariant manifolds...

Feb
03
2010

Workshop on Topology: Identifying Order in Complex Systems

Caging and Linking
Yuliy Baryshnikov
2:00pm|The Hill Center (Core 431), Rutgers, The State University of New Jersey

For a planar domain, a finite point configuration is said to be caging, if the set of Euclidean motions of the domain not hitting the point configuration is bounded. Caging configurations are important in robotics and are a popular topic in...

Feb
03
2010

Workshop on Topology: Identifying Order in Complex Systems

Knotted, Linked and Tangled Nodal Lines in Optical Fields
Mark Dennis
5:00pm|The Hill Center (Core 431), Rutgers, The State University of New Jersey

Optical fields propagating in three-dimensional free space are complex scalar fields, and typically contain nodal lines (optical vortices) which may be thought of as interference fringes. Random wave fields, representing speckle patterns randomly...

Mar
03
2010

Workshop on Topology: Identifying Order in Complex Systems

Topological Robotics, Topological Complexity, and Euclidean Embeddings of Real Projective Spaces
Peter Landweber
5:00pm|S-101

This will be a report on topics related to topological complexity (TC), introduced by Michael Farber in 2003 as a numerical measure of the complexity of robot motion planning problems. TC of real projective space P^n (lines through the origin in...

Oct
06
2010

Workshop on Topology: Identifying Order in Complex Systems

Configuration Spaces of Hard Disks
4:30pm|Rutgers Hill Center, Piscataway

The space of all positions of n disks of radius r in a bounded region has long been studied from the points of view of statistical mechanics and probability. A phase transition is known to occur from simulations, but this is still mysterious to...

Dec
01
2010

Workshop on Topology: Identifying Order in Complex Systems

Patterns, Universality and Computational Algorithms
Nigel Goldenfeld
4:30pm|S-101

Can we use computational algorithms to make accurate predictions of physical phenomena? In this talk, intended for non-experts, I will give examples where complicated space-time phenomena can be exquisitely captured with simple computational...

Apr
06
2011

Workshop on Topology: Identifying Order in Complex Systems

Using Computational Algebraic Topology to Characterize Chromosome Instability in Cancer
Javier Arsuaga
3:00pm|University of Pennsylvania, David Rittenhouse Lab., Room A6

DNA copy number abnormalities (CNAs) play an important role in cancer, and are associated with tumor progression as well as clinical outcome. Using microarray based comparative genomic hybridization (CGH), analysis of CNAs across large cohorts of...

Apr
06
2011

Workshop on Topology: Identifying Order in Complex Systems

Persistent Cohomology and Circular Coordinates
Vin de Silva
4:30pm|University of Pennsylvania, David Rittenhouse Lab., Room A6

High-dimensional data sets often carry meaningful low-dimensional structures. There are different ways of extracting such structural information. The classic (circa 2000, with some anticipation in the 1990s) strategy of nonlinear dimensionality...