2002-03-19 Physics, Eritrea, School

physics

This week has seen a weird yet strikingly compelling confluence of topic in three of my classes: particle physics, non-commutative analysis, and group theory. This should not really be all that surprising, as these subjects are tightly related. Nonetheless, I always enjoy the sensation that occurs when the undulations of discussion that hitherto have been separate come into phase and interfere constructively.

The last lecture in NCA class was about how a spherically symmetric potential and Schrödinger's equation give rise directly to, for example, conservation of linear momentum. Chapter four (Symmetries) of Griffiths' particle physics book is particularly interesting. Griffiths refers to Noether's Theorem, which says something about symmetries and conservation laws being directly related. Invariance under translation in space leads directly to conservation of linear momentum; of rotation, angular momentum; of translation in time, energy; of gauge transformation, conservation of charge.

Another thing I've been thinking about lately is an axiomatic approach to physics. The traditional way of teaching physics is by historical narrative: by explaining the sequence of physical models and the experiments that disproved them. That's probably a very good way to teach physics, since the physics process is just as important as the physics results, and it's a process that will doubtlessly continue indefinitely. But in the case of particle physics, I think it would be amusing to present an axiomatic construction. Start by saying, ``There are the quarks, the leptons, and the gauge bosons. They have these properties...'' and see where it goes.

Such an axiomatic presentation is really inappropriate, since it implies that we know that this is the way things are... and we really don't. But still, there's some appeal in it, just like in mathematics. Speaking of which, I think that at some point mathematics and physics will really converge into a single subject. The main difference between physics and mathematics might be that in mathematics we state the axioms and then explore the resulting effects, whereas in physics we observe the effects and search for the axioms.

Eritrea

`Had a funny little conversation with the dude at ICA Foodman while on my 22:58 chocolate-buying errand. He asked how Mom was doing, apparently remembering us from some weeks ago, so we started talking. His name is something like Hej'da. He's from Eritrea. He said, ``Betcha don't know anyone else from Eritrea,'' and I replied, ``Actually I do... his name is Abraham,'' and he said, ``Ah, Abraham!'' Anyway, Eritrea is a little country on the west coast of the Red Sea, sandwiched between Sudan, Ethiopia, and Djibouti.

school

Classes I want to take:

1. Numerical methods
2. Algebraic Topology
3. Complex Analysis
4. Electromagnetic Fields

Of course those are only the technical classes I want to take. I also pretty much want to study the whole undergraduate curriculum in American Studies and in Geography. Sometimes I really wonder whether it's a waste of time to study subjects like the above at a place like Berkeley; these subjects can be learned holed up in a small room with the appropriate books and a lot of paper and sharp pencils. It's the softer subjects like culture that require group discussion. Standing perched at the final edge of semester number eight and peering down into the last remaining semester is a bit sobering. If only I knew the value of four years at Berkeley when I began!

I wish there were some clever ruse that would give me more semesters at Berkeley. But the truth is they'll let me stay there only one more, and I have to decide how it will be used. In a sense that is good. It's forced progress. If there weren't a limit, it would be very difficult to leave. The other thing is that it's nice to be in the same age group and general position in life as the majority of other students. Similarly I'd like to stay here to do some of the things I wasn't able to do this year. Of course, the real answer is to do it right the first time. carpe diem and all that.

I have this nagging feeling occasionally that I'm wasting my time. Taking all these classes in bizarre subjects like error correcting codes, history of the swedish welfare state, applied non-commutative analysis, and biomedical signal processing, instead of focusing on the hardcore basics, like calculus and algebra and maxwell and schrödinger and heisenberg and feynman's equations. My transcript isn't particularly good -- not strong in any particular subject, nor showing stellar grades by any measure -- so I don't know how I'll be able to get into an interesting Master's program. It would pretty much have to rest on the strength of recommendations from summer internships...

Back to the technical subjects I want to study. I wish there was a way to take them as correspondence classes. You know, I study the books, someone assigns me problems, I mail them homework, eventually take an exam or write a paper or do a project or something. I think that's exactly the way I'd like to study those subjects. Getting credit or being paid for something are pretty much the only circumstances when it will actually get done. Otherwise the things for which I actually am getting credit or being paid for get in the way. I wonder what kind of library the Weizmann Institute has.

misc

Figured out RCS and started using it to track revisions of documents like this one. Would like to either stuff all this into a database, or mark it up in XML and then use XML Style sheets to generate XHTML. That would be kind of neat. I could have it automatically mark up countries and books with the appropriate links.

Dinner at Kalmar Nation: couscous with meat sauce, green beans, scones; chocolate pudding.

Dinner at Kalmar Nation	SEK 35
ICA Foodman: chocolate	SEK 23