Wednesday, October 4, 2023

Autumn 2023

 


5 Oct (Thursday), 2pm

Duston Wetzel

Triply periodic and polyhedral helical weaves


Video

Wednesday, September 27, 2023

Autumn 2023



P.P. Rubens: Bacchus 

28 September

K.V. Shajesh

Negative mass: A runaway solution


Video


Sunday, September 10, 2023

Autumn 2023

A. Pasieka: Lorenz Attractor

Thursday, Sept 14, 21  (2pm, Nc 356)

Mike Sullivan

Geometric Lorenz Attractor

Video of Day 1
Video of Day 2



Here are links sent by Mike:


Plus, this is a series of well done videos on chaos theory. Number 7 covers some of the topics covered in my seminar talks.


Abstract of the talk:  The Lorenz equations, developed and studied by the meteorologist Edward Lorenz in the 1960s, were one of the first examples of a chaotic system. They are a set of three nonlinear ordinary differential equations in three variables. The trajectories move toward a bounded subset of $\mathbb R^3$ and then seem to oscillate about, but never truly repeat. Mathematicians began studying these equations using both quantitative and qualitative methods. The former proved very difficult. The latter yielded results. Guckenheimer and Williams developed a geometric model with behavior similar to the Lorenz equations. Then Birman and Williams used topological methods to analyze this Geometric Lorenz Attractor. Decades later it was proved that the two systems are equivalent.

Participants should have had basic undergraduate courses in differential equations and linear algebra. We will begin with a review of systems of ordinary differential equations. This should last about 20 minutes. Then we will cover the construction of the Geometric Lorenz Attractor. That should take about 30 minutes. Next week we will cover Birman and Williams' proofs of the knot types of periodic orbits in the Geometric Lorenz Attractor.

This material was originally covered last Fall in my MATH 405 course. For now, you may wish to amuse yourself with this video.  


Wednesday, April 26, 2023

Spring 2023


27 April (Thursday), 2pm

Duston Wetzel

Gyroid and the triply periodic helix linkages

Video

Monday, April 3, 2023

Spring 2023

6 April (Thursday),
13 April, and 20 Apr.

Robert Owczarek   (University of New Mexico)

Proto-topological (Quantum) Field Theories of Kijowski and Sławianowski

Video of Part 1
Video of Part 2
Video of Part 3

Here are some links suggested by Robert:
1.  Seminar talk by Kijowskiego from the last year
2.  Related topic on variational principle.  

Abstract: Topological quantum field theories that are metric independent, like, e.g., Chern-Simons theory, give topological invariants of manifolds and knots. Classical field theories of Kijowski and Sławianowski are metric independent, and are defined on manifolds of a priori any dimension, and thus may give new topological invariants of manifolds.

In this talk, I will try to make a friendly introduction to these theories.   


Saturday, March 11, 2023

Spring 2023

From Treewewal
23 & 30 March (Thursdays)

John McSorley

Graphs with trees of certain types, and related topics

Video of Part 1
Video of Part 2

Wednesday, March 8, 2023

Spring 2023


9 March

Mohammad Sayeh

Neural networks and the global minimum problem

Video (there is a 20 min break in sound)

Sunday, February 19, 2023

Spring 2023

Thursday, 23 Feb

Annie Yojaira

Micropatterning with sugar
(on surfaces, curvatures, and nanoscales)


2pm, Neckers 356

Video

Wednesday, February 1, 2023

Spring 2023


Thursday, 2 Feb -- part 1
Thursday, 9 Feb -- part 2
Thursday, 16 Feb -- part 3 

Mathew Gluck

From the isoperimetric inequality to scalar-flat Riemannian metrics

Neckers 356, 2pm

Abstract:  We shall discuss whether a given compact Riemannian manifold can be deformed in an angle-preserving way to achieve constant scalar curvature (so-called Yamabe's problem).

Part 2 -- video

Part 3 -- video

Thursday, December 8, 2022

Fall 2022

8 Dec, Thursday, 2pm 

Jerzy Kocik

On spin and spinors

Wednesday, November 16, 2022

Fall 2022

 

17 Nov and 1 Dec

Jerzy Kocik

On French cafés, invariants, Cauchy formula, permutations, generalized determinants, and a Fock space.

[Neckers 356, 2pm]

Video of Part 1 - very bad sound

Tuesday, November 8, 2022

Fall 2022


 10 November

 Charith Atapattu and Kalpa Madhava

Octonionic calculations with Python


Video

Additional links:

pyOctonion Code in Github Repository,

Pypi repository code where you upload the package to install using “pip” in python,

Library documentation,