Neues vom Nordkap

29.07.2005 10:45

moving windows

Yesterday the system here at the institute was finally upgraded to Sarge.
I am working right now under KDE 3.3, if I run matlab in the shell, the graphics windows move to the right by some pixel every time I switch between the command window and the graphic window. This is a bit disturbing. Sometimes a graphics window even chooses to move over the whole screen to the very right of the screen. I am sure you can turn this off, but it will take hours searching in thousands of menus. Maybe I should really switch to another window manager, KDE is become larger, slower and more windows like with every update. Not the development I am fond of.

27.07.2005 18:33

shoot to stun

Why didn't the British police use one of these tasers on that poor Brazilian? Wouldn't this be enough to prevent a suspect from blowing himself up? You can't pull the trigger of your bomb if your stunned. Can you?

27.07.2005 16:12

Ma no!

Once we have a really good swimmer... Flavia Rigamonti (2. over 1500 m freestyle in Montreal) is SWISS.

25.07.2005 16:26

Lance, the robot

A French specialist in modern training methods, Antoine Vayer, has calculated that Lance Armstrong runs his body at about 550 Watt for a period up to one hour*. Comparable power is usually only reached by athletes on much shorter exploits, like for example 400 m races, who haven't been doing it for the last days or weeks in a row.
So probabely wo is right, Lance is a robot. Lance, the human, died some years ago of prostata cancer, so they took his body and planted that cycling robot inside. His wife apparently thought he was a bit odd, ever since he left the hospital, that's why they separated. And Sheryl Crow, she probabely just gets a lot of money for starring.
Now they have to withdraw him, because everybody would get even more suspicious if he continued winning up to an age of 56.
But who are they anyway? The Bush administration, I guess, they never liked those bloody French.

*I got these numbers from todays NZZ, but Vayer published this in his book called L.A. Confidentiel.

20.07.2005 17:51

schwinger model

I have been fighting with now for some days, trying to understand what is going on in this model. So I will just try to write down, how I believe it works. This is just a kind of a very brief memo.
The massless one flavour model,
$\mathcal{L}[\bar{\psi}, \psi, A_{\mu}] = \bar{\psi}(x) \left[i\gamma_{\mu}\partial^{\mu} - g_0\gamma_{\mu}A^{\mu}(x) - m_0\right]\psi(x) - \frac{1}{4}F_{\mu \nu}F^{\mu \nu} \hspace{1cm} \mu, \nu = 0,1$
i.e. at $m_0 = 0$ has $U(1)_V$ and a $U(1)_A$ gauge symmetry. Since the gauge field $A_\mu$ has only two degrees of freedom, it can be cancelled by a gauge trafo. Such that we arrive at the Lagrangian of a massless free fermion. But since the $U(1)_A$ is anomolous, this is only true at tree level. At a one loop level we get the non trivial Jacobian which can be expressed by a massiv Boson field. So we have a massless meson, which can be expressed as a Boson field through the bosonization thingy and the massiv one from the anomaly.
At $m_0 \neq 0$ the massless meson gets a mass through the explicit breaking of the chiral symmetry by the mass term.
For the two flavour model, the chiral anomaly appears only in the singlet, so the singlet remains massiv even in the chiral limit, where as the triplet becomes massless. It's in fact completely analogous to the $N_f = 1$ case.

I don't measure the singlet. In fact I never saw any signal in the singlet channel, that's why we gave it up. This anomaly term, at least as you have it in 4d, is not gauge invariant. Since all I do in the code is gauge invariant (by the $U(1)_V$ ), doesn't it make sense that is isn't there? Shouldn't it then just be 0 in the gauge average. So it would then be necessary to fix the gauge to calculate it???? =%-$
Ick weess nich, this is for people who understand something of lattice gauge theories not for me.

20.07.2005 10:25

United against ugliness

Angie is supposed to present herself in the east of Germany, as one of theirs, i.e. an Ossi.
What does this mean? Worse haircut, worse clothes, more complaining about everything? Brrr
I am happy, I have no TV.

08.07.2005 16:45

war on terrorism

I believe we will have to live with the risk that something like yesterday's attacks could happen anytime. Everywhere. At least if you want to live in a society where you are not permanently controlled and observed. The famous war on terror is very much the war of everybody against those people who wants to cut our liberty and civil rights, violate human rights under the pretext of protection against terror, etc. In this sense United States lost the struggle. They did it by not speaking out loud against their government after 9/11 and confirmed it by reelecting it. (The patriot act, Guantanamo, the lies that lead to the war in Iraq, Abu Ghraib, all this is enough to send those guys to Mars.)
I very much believe we can do better here in Europe. But we must look very carefully at what our political leaders do and what our fellow citizens think. It all starts with the way we treat muslim citizens in our own countries. Wether we are able to distinguish between those bastards who do the killings and thousands who are threatened by it despite of having the same religious affiliation.
You can't erradicate these terrorists with a classical war, by using weapons I mean. The only thing you can do, is to try to change our attitude not only towards the muslim world, but toward all poor countries. This will maybe lessen the impact of radical ideas on people who feel frustrated because they don't see how they will ever get a part of the pie. Maybe this will help in the long term. But certainly there will allways be some crazy idiots.