Tevatron Beams Turn On At FermiLab

skwang writes: "This press release at Fermi National Accerator Labratory (FermiLab) announces the start of "Collider Run II." FermiLab collides protons and anti-protons in order to study high-energy phyisics (HEP). One of the labs goals is to find the Higgs Boson, an elementary particle that couples with mass. More information about Run II Physics can be found at the FermiLab Web site or at the detector Web Sites: D-Zero (D0) and Collider Detector at FermiLab(CDF)"

Comments

Re:too bad the Standard Model just got clobbered!

[funkbrain]

You seem to have some serious misunderstandings about this...

First things first, he experiment to which you refer is the g-2 experiment at Brookhaven ; it is an experiment to measure the anomolous magnetic moment of the muon (which is a fermion, not a boson).

The anomolous magnetic moment of the muon is a physical quantity predicted by the SM (a prediction which is itself a paramaterization of other measured quantities, and thus has some uncertanty). The g-2 experiment yielded a value which is 2.5 standard deviations away from the SM prediction.

This is a good thing for physicists (specifically the ones at Fermilab)! For one thing, no serious physicist has ever believed that the standard model is a complete description of nature. There are aspects of the universe for which the standard model cannot account (for example the obvious matter-antimatter asymmetry...).

The really exciting thing about the g-2 result and it's potential impact on the physics about to happen at Fermilab is that it is highly suggestive of new physics (i.e. supersymmetry... susy).

Think of the progress of scientific thought in the past 600 years. Newton's gravitation is a good theory; it makes predictions which mach quite well with observation (experiment). However, it is incorrect... along came Einstien's theory of gravitation, (General Relativity, which itself is a good theory, but not the correct one) which reproduces all of the predictions of Newtonian gravity, and and "does one better" by getting right what Newton got wrong (i.e. precession of the orbit of Mercury; the deflection of light by massive objects...).

So we have the standard model, which is by far the most successful physical model in human history. Yet we know it's wrong. But untill we find a better description of nature, it'll have to do.

The standard model is far from dead. It will evolve, in some sense, into a better description of nature.

Re:too bad the Standard Model just got clobbered!

[FredGray]

Hi, folks,

I'm a graduate student who works on the experiment to which this thread is alluding. It is the muon g-2 experiment.

The post to which I am responding contains several factual errors:

• There is about a 1 or 2 percent (rather than 10 percent) probability of obtaining this result by chance if the "true" value is given by the Standard Model. In any event, this is a probability of obtaining the result because of a statistical fluctuation, rather than a mistake (as implied by the phrase "their data is incorrect).
• We actually use GNU/Linux for the vast majority of our data analysis! Our data acquisition system, which moves the raw data from the electronics to DLT tapes, is based on vxWorks. Essentially every other step in the analysis chain runs on Linux machines, either at Brookhaven or one of the collaboration institutions. For instance, we have a cluster with twelve dual 500 MHz Linux machines in our group here at the University of Illinois.
• In some sense, the experiment has already been repeated. The result that we recently announced was based on an analysis of only about 20 percent of the data that we currently have on tape. We're working hard on getting the rest of it analyzed, though: hopefully we'll have an answer by the end of the year. Then I can write my thesis, add "Ph.D." to my name, and start collecting the kind of salary that IT people make straight out of high school. :-)

Thanks,
Fred Gray

Aha!

[jjeffries]

I guess this explains the splattered whale carcass and smashed flower and pot in my front yard...