Tag Archives: math

Knots and the Fourth Dimension

Free food! From Typhoon! Also, math. The Sexy Primes (Undergrad Math Club) present:

Knots and the Fourth Dimension with Professor Constance Leidy!

Take a piece of string, jumble it up, then seal the ends together. The result is a knot. Notice that you can’t untie the knot because you’ve permanently sealed the ends together. (If we don’t jumble at all, we’ll just end up with a circle, which we call the unknot.) We call two knots equivalent if you can move one jumbled piece of string to look exactly like the other without cutting it open. Knots naturally live in 3-space. We’ll discuss a different equivalence relation called concordance involving the fourth dimension. A knot that is concordant to the unknot is called a slice knot. We will discuss some joint work  that shows that knots in a certain family whose slice status was unknown are in fact not slice.

Date: Oct. 11
Time: Noon – 1:00 PM
Place: Woodhead Lounge, Exley Science Center
Cost: Free!

Undergraduate Mathematics Colloquium

Speaker: David Puelz, ’11

Abstract: How does your iPhone’s or TomTom’s GPS work? Why is it sometimes inaccurate? Or better yet, how can we quantify and analyze these inaccuracies? The Global Positioning System (GPS) is a space-based global navigation satellite system that provides reliable location and time information given an unobstructed line of sight to four or more GPS satellites. The configuration of the GPS satellites has evolved to provide the most functional system for the broadest class of users given a limited amount of resources. However, evaluation methods of the current GPS system utilize only four satellites in view, while increasing the number of satellites to determine position will always increase GPS accuracy. In this talk, I’ll develop intuitively meaningful expressions for a GPS performance metric that utilize information from all satellites in view. I’ll also develop explicit expressions for the metric’s first and second derivatives and construct efficient methods for analyzing GPS coverage. All are invited.  Lunch from Iguanas Ranas will be served.

Date:   Friday, April 22
Time:   Noon – 1:00 PM
Place:  Exley 139

Constructible Numbers: An Introduction to Algebraic Structures

Greek geometers puzzled over the figures which they could construct using only a traditional compass and straightedge, but they puzzled even harder over the figures which seemed impossible to construct using those same tools. Given a circle, is it possible to construct a square with exactly the same area? Given a cube, is it possible to construct another one with exactly twice the volume? After two millennia, it turned out that these kinds of geometric questions could be answered in purely algebraic terms. This talk will introduce students to basic notions of algebraic structures via traditional compass and straightedge constructions in two dimensions.

The material presented in the talk will be entirely self-contained; no prior knowledge of or background in mathematics will be assumed.

Free pizza!

Date: April 15
Time: Noon – 1:00 PM
Place: Exely 139

Scientific Computing and Informatics Center (SCIC)

The SCIC would like you to know that it is there for you when you need it. If you don’t know what it is, here’s some information:

The Scientific Computing and Informatics Center (SCIC) at Wesleyan is aimed at facilitating the effective use of the University’s new high-performance computing (HPC) facility and supporting the educational initiatives of all Wesleyan faculty and students who would like to utilize any of the community’s considerable computational resources.

We currently have tutors who specialize in C, Perl, Python, SQL, Visual Basic, Shell Scripting, Unix, PyMol, Matlab, Mathematica, Cluster (HPC) Computing, Amber, Xmgrace, Chimera, AutoDock, VMD, Informatics, and Relational Databases.

Whether you need help with a collaborative or independent research project, help with an assignment or a class, or help just learning a new skill, we’re here to help!

  • Where: Exley 105
  • When: Sunday – Thursday, 5:00-10:00PM
  • Contact: Adam Robbins-Pianka (email: arobbinspian(at)wesleyan(dot)edu, tel: x3957)
  • For More Information: http://www.wesleyan.edu/scic/