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Room Change Announcement: We have changed rooms for the rest of the Mathclub talks this semester. We will
now meet in B139 Van Vleck at the same time.
May 4, 2009
Proofs by Counting
Abstract:
In the meeting, we will count some more and prove some well known math results
such as the formula for the geometric series, the infitude of primes, and
Fermat's little theorem. Come and see why Proofs by Counting are appealing.
April 27, 2009
Who is Srinivasa Ramanujan?
Abstract:
Who is Srinivasa Ramanujan? With virtually no formal training in mathematics, it's a wonder that renound English number theorist G.H. Hardy "discovered" the man
behind hundreds of pages of scribbled formulas, some so deep that they remained a mystery for decades. Learn more about the legacy of mathematics surrounding
this young visionary, and his influence on fundamental areas of present day mathematical research in number theory, combinatorics, and modular forms.
April 13, 2009
Packing Spheres and Correcting Errors
Abstract:
I'll will give a very basic overview of two problems:
1. How can we pack oranges into a box as tightly as possible?
2. How can we reliably send a signal in a noisy environment and be
sure that the target receives the message exactly as we sent it?
The point of the talk is the surprising fact that 1 and 2 are
essentially the same problem.
April 2, 2009
Mathclub Movie Night
If you haven't come to a Math Club event yet, this is your chance!
Come chat with other math junkies, meet the Math Club officers, and
find out what we're all about! Food will be provided by Jamerica, but we also encourage
everyone to bring a dish to pass (even if it's just chips, soda, or
cookies!) Don't have a dish to bring? We still want you there!
March 30, 2009
Markov Chain Monte Carlo
This talk will provide a gentle introduction to the topic of Markov chain
Monte Carlo (MCMC) and apply this computational tool to the
problem of estimating gorilla divergence times from individual
DNA sequences. MCMC is a computer-based simulation tool for
taking dependent samples from general probability
distributions. I will aim to provide the audience with an
intuitive understanding of how MCMC works, a description of
the most common form of an MCMC proposal algorithm, and a
brief explanation of the theoretical justification for the
methods.
March 2, 2009
What is a Group Ring?
As the name implies, group rings are a meeting place
for group theory and ring theory. They serve as a tool
in group theory and in ring theory, and they are
interesting, easily defined, objects in their own right.
In this talk, I will quickly explain how group rings are
defined and briefly mention some applications. For the
most part, I will discuss how group rings of infinite
groups are studied, including some of the successes and
also some open, quite difficult, problems.
February 16, 2009
The Geometry of Molecules
All of us have grown up doing puzzles. But, did you
know that your body works by matching the geometries
of molecules? For example, this is how you become
immune to a disease. Your immune system works to create
a shape that is a match to the invader.
I will talk about how mathematics can be used to understand
molecular geometry, and how understanding this geometry can
be used to design new cancer drugs and other useful molecules.
Along the way, you will learn what a gene really is and why
mutations in our genes can cause diseases.
I will try to describe everything in basic, intuitive terms
and hope that anyone with an interest in math and science
will enjoy the lecture.
November 24, 2008
Math Club Elections
Elections were held on Monday the 24th for the
offices of President, Vice President, Activities Chairs, Treasurer, and Webmaster. The results are as follows:
President - Tess Anderson VicePresident - Ruth Stoehr Activities Chairs - MengMeng Chen and Zhizhong Pang Treasurer - Daniel Lecoanet PR Chair - Sally Wolfe Web Master - Sean Finley November 10, 2008
Ramsey's Theorem via nonstandard numbers
In a room with sufficiently many (18) people there are four people who either all know
each other or are all do not know each other. This is an instance of Ramsey's Theorem.
There's also an infinite version of Ramsey's Theorem, which says that if you could put
infinitely many folks in a room, then an infinite subset of them would either all know
each other or all not know each other.
It turns out we can prove both versions of Ramsey's Theorem using nonstandard natural
numbers. Nonstandard numbers are infinite numbers that act just like finite numbers
because they don't know they're infinite. However, we know they're infinite, and we'll
use that to our advantage. Pizza.
October 27, 2008
Arrow's Theorem on the impossibility of a fair election.
A Famous Theorem of Kenneth Arrow (a Nobel
Laureate in Economics) says that it is impossible
to have a fair election among three or more candidates.
More precisely, there is no election procedure which
satisfies certain principles of fairness that we will
make precise in the talk. The proof consists in
showing that, given an election procedure, the
aforementioned fairness principles imply that a certain
family of subsets of the electorate is an ultrafilter
(this is not a type of coffee filter).
Click here
for a partially written exposition of the talk.
We will eat
pizza as we consider
the ramifications for the upcoming election!
October 13, 2008
An Investigation into the size of integer subsets
What is the probability that a truly random positive integer is prime? How about square?
Squarefree? You may be familiar with the divergence of the harmonic series, but what can
we conclude about the reciprocal sum of various subsets of integers? These questions and
more will be answered, intuition will be both confirmed and betrayed, and still more
mysteries will be left open as we explore the intricacies of the most elementary infinite
set in all of mathematics.
This material is completely accessible to anyone with a working knowledge of elementary
sequences and series, and you must like free pizza.
September 29, 2008
The Mercedes Knot Problem
Have you ever noticed that
long extension cords are twisted many times?
There is a mathematical problem that is closely related
to this phenomenon and whose solution is
illustrated in
this sequence. In the talk the details will be provided,
along with FREE PIZZA!!
Click here
for a longer description of the talk.
September 15, 2008
How to recognize an equilateral triangle
Think you know how? Come and find out, and enjoy some free pizza!
Here is the
poster.
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