Friday, July 31, 2009

OU Summer School (Quantum Mechanics - SMXR358)

Just back from Open University summer school, a week at Sussex University near Brighton doing experiments in quantum mechanics (course SMXR358).

Saturday July 25th

The school proper stared with a lecture on spectroscopy and notation. I guess this was never going to be riveting, but it’s essential for many of the experiments. The problem is that the necessary – and quite complex – theory is covered in the first few chapters of Book 3, which we're not meant to have started yet. So if you were orthodox on the study schedule, the lecture (and, sadly some of the experiments) must seem pretty incomprehensible.

However, there is always someone in the audience smart and well-informed enough to point to a subtle error in the lecturer’s slide pack (no such thing as a 1p state). How the other students must have hated that person!

Afterwards we all retired across the road to the lab common room for the ice-breaker. This started as doleful and frozen as I had anticipated. I wandered around looking for people with group B on their badges, as these people were candidates to be partners tomorrow in the lab, but without much success.

Mark, the course director, then intervened to correctly separate people into their groups for a pub quiz (sample question: how many concrete cows in Milton Keynes?). Each of the four groups A-D was split into two, and of the eight contending teams there were three winners with 7/10. I was ridiculously pleased that one of these groups was mine.

An early breakfast tomorrow as we start at 9 a.m.

Sunday July 26th

Sunday is a working day at summer school. After the 9 a.m. lecture, we assembled in the lab, milling around until the fateful moment when the tutor said “Oh, by the way, we do these experiments in pairs. Perhaps you’d like to team up?”

I think there must have been some covert pairing the previous evening as twosomes quickly began to drift off in search of apparatus. I looked around for anyone still free and quickly cut a deal with a guy who, I found out, works at the Joint European Torus (JET) fusion project in Oxford. Good choice!

In fact our first experiment was a simple measurement of exponential radioactive decay, and to handle the slightly-radioactive Barium137 I had to dress up in a pinny (pictured), or as we like to say, in a very scientific and vaguely-white coat.

The author in authentic scientific gear for handling 137Barium

When you’ve finished taking measurements, you enter the results into an Excel spreadsheet on one of the many PCs in the lab. Then you push in a memory stick to take the resulting file home with you. I walked across to a PC which someone else had been using – there was a memory stick already pushed, but the owner had wandered off.

How cute! The memory stick had some holiday photos on it which had auto-opened and were brightly displayed on the screen in preview mode. Most of the photos showed tropical beach scenes, but right in the centre there’s this attractive girl, big smile for the camera, lifting her tee-shirt up to her chin. Which I should add was all she was wearing.

So I’m transfixed in front of the screen, unable to avert my eyes. The tutor (yes, it was Stan) wanders by, takes in the scene and asks laconically “Yours?”

I weakly shake my head and flee the scene, followed by a calculating look.

Monday July 27th

OK, it’s summer so it has to rain on campus. Today it’s the longer experiments in the lab. We’re looking at the Zeeman effect, and then measuring the spin of the caesium nucleus. The Zeeman effect equipment - for measuring the fine structure of energy levels in the neon atom in the presence of a magnetic field - is complicated,

Equipment for measuring the Zeeman Effect

as is the spectrum we observe through three devices in series: a Fabry-Perot etalon, followed by a spectrometer and finally a telescope. Here’s the diffraction pattern of the neon spectral lines of interest - seen through the telescope before the magnetic field is turned on to split them.

Neon spectral lines from the Fabry-Perot etalon

In the coffee breaks there was much gloom from staff and some of the better-informed students about the financial future of OU – talk of the end of summer schools as far too expensive, of courses without final exams because too many students weren’t turning up (the OU then loses its Government grant for that student), and of contraction in the number of intellectually-rigorous courses in favour of softer subjects where there is greater popular interest or vocational business sponsorship. Apparently there's to be a formal announcement at the end of the year.

What a depressing prospect. Please Mr Cameron, don’t hit the OU too hard with all those public spending cuts!

Tuesday July 28th

Let me get on to swine flu. On the first day the chief OU person here mentioned the procedure in case anyone came down with it. He was vague about the details: call security on 3333 and ‘measures will be taken’. Right, I’ll be looking out for the guys in biowar suits then. But despite the hundreds of people we have here on campus from across the UK, no-one seems ill. Where has the epidemic gone?

I grabbed one of the OU physics faculty here and asked about progress as regards an OU theoretical physics MSc. As I understand the response, there is a desire to do it but progress is at a very early stage. The most likely route is to base such a course on the existing maths MSc programme and add some extra physics modules which would create a course with a mathematical physics feel.

Erwin Schrodinger’s advice to his beginning graduate students, who asked what they should study.

“Year 1, study maths; year 2, study maths; year 3, come back and ask me again.”

Wednesday July 29th

If you’d have asked me before I came, I’d have said that the typical OU student of quantum mechanics would be young, white, male and an NT. (The NT part is the Myers-Briggs/Keirsey personality type they call Rational, aka an intellectual).

Score 2.5 out of 4. The seventy-odd students here are overwhelmingly white and mostly male. The oldsters are outnumbered by the thirty-somethings but not by much. But the intellectuals are truly in short supply.

It seems to me that a very prevalent personality type here is the early 30-40 year old ISTJ who’s a hands-on engineer in his day-job, and is using this course to brush up on the theory. A guy who’s bright but non-abstract, dogged but not big on the big picture. You might say that’s what you would expect on an experimental course, except that everyone here is doing the mainline QM theory course as well.

What’s the effect? I think a lot of people are finding difficulty in seeing the wood for the trees, which is of course an endemic problem in QM. It does require really good lectures, though, to draw out and emphasise the foundational concepts and put some shape on what’s been learned to-date. So far, I’ve found the two-per-day lectures quite uneven.

Thursday July 30th

At this stage of the school, sexual deprivation is beginning to kick in. The polarization experiment requires graphing sin2(2θ) from 0 to π. Strange to see guys lingering over a piece of mathematics on their computer screens! Perhaps the following is the answer.

Flyer for the disco

Friday July 31st

With all required experiments finished yesterday, it’s home again from my last ever OU summer school. I always dread it at the start, thinking about the hordes of strangers, the endlessly complex experiments, the long hours in the lab. And at the end I predictably feel it wasn’t so bad and the stuff all makes more sense now. Without that level of immersion, the maths MSc next year is going to be that much harder.

See also Summer School Vignettes.

UPDATE: Dec 14th 2009. Letter this morning - I received a distinction on this course.