2013
Dec
26

# Yuval Peres

2:30pm to 3:30pm

HOME / Eventss

2013
Dec
26

2:30pm to 3:30pm

2014
May
01

2:30pm to 3:30pm

2017
Jan
22

4:00pm to 6:00pm

Rothberg B220 (CS bldg)

Coherent configurations" (CCs) are certain highly regular colorings of the directed complete graph. The concept goes back to Schur (1933) who used it to study permutation groups, and has subsequently been rediscovered in other contexts (block designs,

association schemes, graph canonization).

CCs are the central concept in the "Split-or-Johnson" (SoJ) procedure, one of the main combinatorial components of the speaker's recent algorithm to test graph isomorphism.

association schemes, graph canonization).

CCs are the central concept in the "Split-or-Johnson" (SoJ) procedure, one of the main combinatorial components of the speaker's recent algorithm to test graph isomorphism.

2013
Nov
28

2:30pm to 3:30pm

2014
Mar
27

2:30pm to 3:30pm

2015
Oct
29

2:30pm to 3:30pm

Title: Avatars of small cancellation

Abstract:

In general, given a finite presentation of a group, it is very difficult (in fact algorithmically impossible) to understand the group it defines. Small cancellation theory was developped as a combinatorial condition on a presentation that allows one to understand the group it represents. This very flexible construction has many applications to construct examples of groups with specific features.

Abstract:

In general, given a finite presentation of a group, it is very difficult (in fact algorithmically impossible) to understand the group it defines. Small cancellation theory was developped as a combinatorial condition on a presentation that allows one to understand the group it represents. This very flexible construction has many applications to construct examples of groups with specific features.

2013
Dec
05

2:30pm to 3:30pm

2014
Jan
09

2:30pm to 3:30pm

2014
Mar
06

2:30pm to 3:30pm

2013
Nov
21

2:30pm to 3:30pm

2014
Jan
02

2:30pm to 3:30pm

2014
Mar
13

2:30pm to 3:30pm

2013
Oct
31

2:30pm to 3:30pm

2017
Jun
08

11:00am to 12:00pm

Levin building, lecture hall 8

Title: “The geometry of eigenvalue extremal problems”

Abstract: When we choose a metric on a manifold we determine the spectrum of

the Laplace operator. Thus an eigenvalue may be considered as a functional

on the space of metrics. For example the first eigenvalue would be the fundamental

vibrational frequency. In some cases the normalized eigenvalues are bounded

independent of the metric. In such cases it makes sense to attempt to find

critical points in the space of metrics. In this talk we will survey two cases in

Abstract: When we choose a metric on a manifold we determine the spectrum of

the Laplace operator. Thus an eigenvalue may be considered as a functional

on the space of metrics. For example the first eigenvalue would be the fundamental

vibrational frequency. In some cases the normalized eigenvalues are bounded

independent of the metric. In such cases it makes sense to attempt to find

critical points in the space of metrics. In this talk we will survey two cases in

2013
Dec
12

2:30pm to 3:30pm