# Research Polymath

## August 2, 2009

### Application

Filed under: Uncategorized — ramanujantao @ 2:17 am
Tags: ,

Hardy used to say that number theory is the purest subject. He was proud of the fact that it had no applications in that time. Now however, it has many applications to cryptography, code breaking etc.. In the same way, quantum entanglement does not seem to have any real practical applications. However this following problem and thought process helped someone solve a problem he was having trouble on involving statistical entanglement. So it goes to show you, many subjects, no matter how pure they are, can have real world applications.

Question. Consider three cities: Philadelphia, New York City, and Trenton. These can be represented by subsystems $A$, $B$ and $C$. Now if we measure $A$, $B$ and $C$ separately, it is impossible to obtain information about the entire system. The information is encoded in the nonlocal correlations between the subsystems.

This problem helped someone in a real world setting.

## July 31, 2009

### Collaborative Learning

Filed under: Uncategorized — ramanujantao @ 4:43 pm
Tags:

As I mentioned in my previous post, I want to experiment with collaborative learning as well. My plan is to start with a Rudin’s Principles of Mathematical Analysis and apply a “polymath approach.” Although I think each post will be a new chapter. Unlike lectures, I think this approach will allow people to learn actively and with questions. Also, one can get many different perspectives of the material.

## July 28, 2009

### Quantum Entanglement: Discussion Thread

Filed under: Uncategorized — ramanujantao @ 7:48 pm
Tags: ,

First of all, we need to gather some resources to tackle this problem. I found John Preskill’s notes on quantum computation to be very valuable. But what about $\mathbb{Z}_3$ is special? Moreover, why are we considering spaces of the form $\mathbb{Z}_p$ where $p$ is prime? As mentioned before here, quantum entanglement can be modelled more generally than tensor products in hilbert spaces.  We can consider cartesian products of various sets. But will this general view help us tackle our more specific problem?

### Welcome

Filed under: Uncategorized — ramanujantao @ 4:52 pm

The purpose of this blog is to encourage collaborative research on tractable research problems. This is much in the spirt of Terence Tao’s polymath blog. I might experiment with “collaborative learning” as well. For example, suppose we want to go through Rudin’s Principles of Mathematical Analysis. Perhaps we can apply a polymath approach to this task as well.

Create a free website or blog at WordPress.com.