Absent-mindedness

The Deutsche Bank knows a lot about me, presumably. Of course they know a lot about all their customers: how much they earn, how much they withdraw for a good night out, how much rent they pay, where they go on holiday and so on. I suppose it is quite unremarkable that a bank knows about my finances, and there is no reason to worry.

The odd thing is that the Deutsche Bank also know very much about my state of mind. In addition to losing two bank cards (could happen to anyone) I managed to forget my PIN (must happen to loads of people) and enter the wrong PIN three times in a row (I knew the numbers were 8-3-6-9, but had forgotten the order, and still have). Twice I took the bank card but left the money, and once I took the money and left the bank card. In fact I thought that I had managed to make every mistake it was possible to make with a bankomat, but today I found a new one: I transferred some money and left the bank card behind. The odd thing is that three hours later I could suddenly remember exactly what I had done and where the card was. In any case the staff took pity on me, opened up the machine and gave me my card back.

Of course they made a note of what I'd done. So in addition to knowing the inside of my wallet, the Deutsche Bank knows quite a lot about the inside of my head.

More about the nature of matter

To be honest I didn't quite finish my post yesterday. So, with a wink to Bildblog which makes fun of germany's best selling tabloid paper, the Bild Zeitung, I present the combined cosmologist/particle physicist picture of the universe. Of course if the Bild Zeitung has a pie chart which has the wrong proportions or where the numbers don't match the amount of pie it is because they are stupid. In my case it is because I used a highly non-linear percentage to angle algorithm.



The title says "Composition of the universe", and the bit below says that the fact that the numbers don't add up to 100% is because we ignored penalty-stopping hero Jens Lehmann.

The nature of Matter

Today I listened to a talk by a cosmologist. I sort of feel that I ought to listen to talks by cosmologists. It sets a good example to my colleagues, and it's the kind of thing that people in the street occasionally talk about. Now quite early on in his talk he puts on his slide which explains what the universe is made up of. And according to cosmologists it is made up to a large extent of dark matter (4% at the latest count).

I am by association a particle physicist. I don't actually know much at all about particle physics, but armed with a good book I can sort of bluff my way through. The best book around, the bible of particle physicists, is the particle data book. This book lists all particles ever found, from neutrons and protons through to tau leptons and rho mesons and much more besides. This all counts as normal matter: these particles somehow interact with light, or each other, and it is possible to prove that they were there.

Of course particle physicists don't believe they have found everything. They leave the door open for new particles, some of which they expect to find, and some which would be rather surprising. You may expect that particle physicists would spend much of their time looking for the other 96% of the universe. Well they don't. If you take a look at the aforementioned bible, you find the following notes about the state of the world of particle physics. There is a lot written about the known particles, which is fair enough. Lots of time and money is spent studying these particles, and lots of people find meson resonances rather interesting. Now take a look at the searches: These are the things which haven't been found yet, but which some people think might be found at some point in the future. And how much of these 100 pages of speculation is devoted to dark matter? A single page (WIMP's and Other Particle Searches). The missing 96% of the universe gets stuck in the speculation:other category. To add further insult note they even added a greengrocer's apostrophe to the poor old WIMP in their listing.

Particle physicists should really spend more time in fights, flame wars and funding battles with cosmologists. I imagine the exchange would go like this.

Cosmologist: Look , you've had 70 years of accelerating stuff, about 100 billion dollars to play with and you've found what makes up 4% of the universe. Give it up.

Particle Physicist: Well a fat lot of use you lot are. What should we be looking for, exactly? Dark stuff, right, good.

C: You know the branching ratios of the 1475 MeV resonance of the eta meson to 5 decimal places, but you haven't a clue what's holding the universe together.

PP: It is quite obvious that you screwed up either your measurements or calculations, and you stuck them back together by inventing matter which by its dark nature nobody can ever disprove. We'll just hang around measuring branching ratios of eta mesons until you get it sorted.

C: Fuck you
PP: Fuck you too.

etc etc.

Rhubarb Cake

My mood this weekend was improved by no end thanks to a rhubarb cake. I baked this cake using this recipe, which is in german. I went for the options of "Muerbeteig", which translates to shortcrust pastry according to my dictionary and "Streusel" which translates apparantly as streusel. I guess you pronouce it as "stroosel" and not like the german "shtroysel" if you are in England, but I really don't have a clue.

Here we note one of my problems in life: I have problems speaking english. There are things in life which I have got to know only in Germany. These include (but are not limited to) skiing, baking cakes, making curries and paying taxes. I did try to follow an american recipe for a rhubarb cake, but just got confused by the funny ingredients. There is also something very assuring about the german use of reproducible standard units such as the gram, rather than the american "cup".

In any case the cake turned out well, but needed longer than an hour in the oven. We come now to the historic moment in this blog, where I say something nice about Germany instead of whinging about how much better things are in England. Drumroll please:

Germans make very nice cakes, and Germany is the perfect environment for baking and eating cakes.

There, that wasn't so hard, now was it?

Leak Chasing

Yesterday I found that the Stern-Gerlach apparatus had a vacuum leak. Molecules in the atmosphere travel only about a tenth of a micrometer before they hit another molecule and go off in a different direction. If you want to get a molecule to fly in a straight line for a whole metre then you have to get rid of most of the other molecules (removing roughly 99.9999999% of them should do the trick).

To do this you need a container and a sucking device (the pump). The pump has the job of removing the molecules, and the container has the job of not letting new ones get in. If everything goes well you will have a vacuum container with practically nothing in it.

The trouble with vacuum containers is that they tend to leak. And they follow Murphy's laws of vacuum leaks.

1/ A vacuum leak will never be quite large enough that you can hear the air whistling through it, but will be large enough to screw up your measurement.
2/ A vacuum leak will always occur at the point in a vacuum system furthest away from a pressure gauge.
3/ A vacuum leak will always occur at point closest to the most sensitive device in your system.

Laws 2 and 3 combine to form the vacuum-system exclusion principle: It is impossible to mount a pressure gauge next to your most sensitive device, usually because you have the wrong connector.

Fortunately laws 2 and 3 can also be used to divine the exact position of your leak. If you want to be really sure you can buy yourself a nice Helium leak chasing device

Bet of the week: snooker

First we take a look at the weeks events in Italy. This plot shows the full development in the chance, as determined by his betting odds on betfair.de, of Silvio Berlusconi becoming the next prime minister.


Last weeks bet was looking good for a while, but it now seems that Romano Prodi will indeed be the next prime minister of Italy. I said to back Berlusconi on Friday morning at a quote of 5.7 (roughly 18%). His quote stayed at this level until the first big drop in his chances (down to 5%) came with the exit polls on Monday, but by the end of the day things were looking up again. Right now it looks very unlikely that he will win, so I think we can write this one down as LOST.

Moving swiftly on, I will go for Stephen Hendry to win the Snooker World Championship. The main reason is that he has a nice graph. I know nothing of his current form, and Hendry is getting on a bit, but apart from Ronnie O'Sullivan, who is rather unpredictable, there is nobody who stands out. So why not go with Hendry, who won it several times in the 90's. And he has a very nice graph

Note how the as the volume increases the fluctuations in price decrease in magnitude. This is all pre-tournament betting, so there are none of the mad reactions to events as seen in the italian election. Let's see how this one goes.

Dancing ist verboten

Good Friday is without a doubt the most depressing day of the year. Not content with being miserable by themselves, the good christians of Germany make sure that everyone else is thoroughly miserable too.

I have been living in Germany for a total of five and a half years, and never once really felt the need to dance on Good Friday. In fact I only ever feel the need to dance when I'm really drunk. Yesterday I found out that there is really a ban on dancing on Good Friday. I'm not quite sure how this is enforced, though. When does a sprightly walk become a dance? Is a hug just the zero-velocity limit of a slow dance? What about jumping up and down? Can you ban people from jumping up and down? "My good Herr. Zat vas sechs Sprungs in eine Minute. sprungen Verboten! VERBOTEN!" I wonder what happens if you walk into a police station and start to waltz through the entrance hall. I really feel that somebody should test the limits of this law.

As far as I can tell there is no law in Germany to stop you crucifying yourself or your friends on Good Friday. I mention this with respect to the least surprising headline of the easter weekend. So go ahead next year with your own private crucifixion, but remember to buy the hammer, nails and wood the day before (all shops are closed on Good Friday), and for christ's sake try not to enjoy it.

Bara Brith

Today I made a welsh tea bread, known to the natives as Bara Brith. My mum went to university in Aberystwyth, Wales, which sort of explains this. The recipe is very easy, but you have to be remember to soak the raisins in tea overnight. I followed these instructions, but took the energy-sparing step of turning on the oven after soaking the raisins overnight. It turned out very well, with a slightly hard (but not burnt) crust and nice and moist in the centre.

Wales doesn't get much press in Germany, somehow. People here think that the whole idea is just a plot by the english to get more votes at FIFA meetings. So heres to the welsh: They have a some great scenary, good food, their own (gaelic based) language and lots of sheep. Why not pay them a visit?

The blood donor

I overheard a very interesting conversation in the changing room of the local swimming pool. A father was explaining to his young son the process of donating blood. As a good father (the kind who takes his kid swimming etc.) he was keen to impress how useful it could be, and how it could help seriously ill people. Then came the following line from the eight-year old:

"wouldn't it be funny if you were in hospital and got your own blood back!"

Of course he said this in German, but those were the sentiments. But why the hell am I writing about this, you ask? And why was I hanging around changing rooms listening to what pre-pubescent boys say? Well the point is that this little boy had just re-invented the climax of what many people in England consider to be the greatest half-hour of TV comedy ever made, without even trying. People, professional comedians, sit around for hours trying to come up with funny ideas and in Germany they usually fail miserably.

So the next time someone tells you that Germans don't have a sense of humour, the correct reply is that they have it removed at the age of 12 or so.

In the bowels of the institute

By far the most interesting part of the physics institute is the basement. This is where people used to work. One of the characteristics of physicists is that they don't tidy up after themselves. They go home and leave stuff lying around. And one fine day they go home and never come back, leaving their things for future generations of physicists or archaeologists to find. Today I found a very nice connection piece for a vacuum system, which made me very happy. I will need this piece for the Stern-Gerlach experiment.

Today summed up my present role in physics. Within earshot of the "kick-off" meeting of the next big thing (a neutrino telescope beneath the sea) I was fiddling around with an imitation of an 84 year old experiment which comfortably sits on a desktop. I am rather happy with this state of affairs. Although I wish the km3netters the best of luck, it is not for me. It may be stimulating to build one sensor, but after you build, test and install several hundred you probably get a bit fed up with them. Once you get into the thousands I can't bear to think.

If I may quote Arthur Roberts (you really want to check out this link)

“Oh, dammit – engineering isn’t physics – isn’t that plain?
Take, oh take your billion dollars. Let’s be physicists again.”

Stern-Gerlach Experiment

Today I started playing with a Stern-Gerlach demonstration experiment, which looks very much like the one above (thanks to Wikipedia). The one here runs with Potassium, though, and has an ionizing wire as a detector instead of photographic film.

The experiment is notable in at least two ways not usually mentioned. Firstly it was something of an accident that it worked at all. Trying to find the quantised orbital angular momentum predicted by the Bohr model, Otto Stern and Walter Gerlach chose an atom (Silver) which has zero orbital angular momentum, which was not predicted and could not be accounted for by Bohr's model. Fortunately enough they chanced upon the property of electron spin, although it took three more years for anyone to postulate spin, and another two for anyone to realise that Stern and Gerlach had measured it.

The other interesting point is that Otto Stern and Walther Gerlach, in a real-life homage to their famous experiment, went their seperate ways. Stern was part jewish and resigned from Hamburg university in 1933 to emigrate to the USA. Gerlach stayed in Germany and after working on Torpedos was put (officially) in charge of the nuclear weapons program. Fortunately for Gerlach and the rest of us, he seems to have been rather overwhelmed by the job. I quote from "the Virus House" by the controversial historian David Irving

Admirable though [Gerlach's] personal qualities were, he did not abound in energy and drive. Those who knew him then, and those who visit him now, retain an impression of an outstanding scientist imprisoned behind a desk heaped with reports, papers and documents through which he laboriously works, while never quite getting to the bottom. The calendars on his wall are over eight years old, the surface of his desk is seldom seen. Very soon the [Reichsforschungsrat] was sending [Gerlach] exasperated letters asking for the long-overdue bimonthly reports on nuclear physics to submit to [Hermann] Goering. They were met with a wall of silence from Gerlach's flower and plant bedecked Munich institute

In 1943 Stern received the Nobel prize in physics for "for his contribution to the development of the molecular ray method and his discovery of the magnetic moment of the proton". Gerlach has the distinction of being the eighth most nominated physicist to never receive a Nobel prize. Presumably Hitler's 1936 ban on Germans receiving Nobel prizes didn't exactly help his cause.

Stern and Gerlach both survived the war, continued their work as physics professors and met just the once afterwards.

Links:
Description of the experiment:

A complete history of the experiment:

A free download of "The Virus House" by David Irving, who may be a holocaust denier, but is one of the few historians who can speak german, understand physics and write entertaining prose.
Click Here

A very entertaining analysis of Nobel recipients, which reveals who the unluckiest physicist of all time is:
Click Here

Cricket Match

In a bid to stave of homesickness and civilise Germany (or at least a small part of Bavaria) I organised a game of cricket yesterday. I am on a steep learning curve here. I have learnt that a rasp is coarser but much quicker than a file. I have learnt the expensive way that if you want to buy a cricket bat cheaply on a german flea market the correct opening line is "Was is denn das fuer ein komisches Stueck Holz?" [1] and not "Ein Cricket Schlaeger! Wie schoen, so was wollte ich immer haben" [2]. I have also learnt that the action to bowl a cricket ball is the same as the action used to throw a hand-granade (thanks to Marc). I could have sworn that he at least once he tried to pull the pin out of a tennis ball before starting his run-up. On the whole the game was a success, and I have three converts to the game. Next week: reverse swing, googlies, doosras, tea breaks, how to shout "how's that" in a more convincing manner.

[1] translation: What is that strange piece of wood you have there?
[2] translation: Please accept my life-savings, house, belongings and the hand of my eldest daughter in exchange for your cricket bat.

More Testing...

I made a very nice post, published it, saw it as preview, published it again, but it doesn't appear in the blog. I have the feeling that I screwed up somewhere. Maybe this one will appear?

Bet of the week

This is the chance of Silvio Berlusconi being the next prime minister of Italy, according to betfair.de (09:58 Fri.) The y-axis shows the implied probability of him winning the election this weekend, the x-axis shows the betting trend over the last weeks. You can get odds of 5.7 on Berlusconi, so for an outlay of 10 Euros you would claim 57 Euros if he wins, which would be a profit of 47 Euros. I spoke to my "Italian connection" in the pub last night, and he said that although he wanted Berlusconi out, he wouldn't be voting because of the difficulties posed by Italian beaurocracy. From this straw poll of one person, I say back Berlusconi. He seems like the kind of guy who gets the ballot boxes filled, one way or the other.

Testing testing 1 2 1 2 .

Hello, is there anybody out there?