Sunday, October 29, 2006

Needed : math

Hi all,

I was faced with a problem this week. Well, several problems. The start of it all (the meta-problem if you will) was te realisation that dawns on you constantly when you try to do anything in string theory, and any branch of theoretical physics for that matter; I don't know enough mathematics.

Fair enough, this is where we get some studying done. The plan for the coming weeks is to get a good grasp of differential geometry. It's pretty hard to find a good text that describes it at the level that I need. I don't need it to be too rigorous (my apologies to the mathematicians), but it needs to be rigorous enough. I think that my long search is over. Prof. Gary Gibbons from Cambridge was kind enough to post the following lecture notes on his website

Applications of Differential Geometry to Physics

The notes are from a Part III course in Cambridge, which seems to be exaclty what I need.

The main reason why I need this is that I want to understand more about vector bundles. Remember that I'm working on gravity in the string theory context? Well, gravity is described by General Relativity, who'se mathematical language is that of tensor calculus on manifolds. I'm trying to use methods found by my advisor to construct exact solutions that hopefully will shed some light on the high energy behaviour. These methods arised in the context of gauge theories, which are described mathematically by symmetry groups called Lie groups. Fibre bundles (at least to me) seem to be the natural bridge between the two. Apparently, gauge fields can be seen as connections on vector bundles. This is what I want to understand better.


Saturday, October 21, 2006

Social and other gatherings

Yesterday was fun. A professor in my department decided to hold a little social gathering at his appartment in Brussels. The original pizza plan was foiled, due to the cook of his usual pizza place being abroad for the pizza world championships (no, I'm not making this up...), but in the end it all worked out and we had a nice meal.

So what happens when a bunch of string theorists get together with a few bottles of wine? A very interesting discussion erupted about the nature of mathematics and it's relation to physics. We also agreed the landscape was rubbish ;-)

The next few weeks will be very busy. I will be attending a graduate school about nonperturbative aspects of quantum field theory, supersymmetric QFT's, string theory and D-branes. Speakers will include Frank Ferrari, Ludwig Fadeev, Ben Craps, Carlo Maccaferri and Riccardo Argurio. Should be fun, but it will take up a lot of time. Wait, weren't the days of attending lectures all day over...?

In conclusion, some random pictures from various parties last week

Thursday, October 12, 2006

Colloquia en Lectures

Some news about that new aspect of my new life, qolloquia, symposia and the likes.

Next week I'm invited to the following :

Solvay Colloquium by Professor C.N. Yang

The Inaugural Lecture of the 2006 International Solvay Chair in Physics by Professor Ludwig Fadeev

Sounds fun doesn't it? I'm going to attend, but I'll mentally prepare myself that I will be feeling rather stupid afterwards.

As for other news... all I can say is : curse Blackadder DVD's! I really ougth to have gotten more work done yesterday. No matter, I'll make up for it today.

Party tonight as well. I'll post op pictures if I don't forget my camera.