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buzzlightbeer
2005-Aug-17, 05:10 PM
an international collaboration of particle physicists has made new measurements that shed more light on the weak force, which is responsible for radioactive beta-decay.

The results, which agree with the Standard Model, show that the strength of the weak force acting on two electrons lessens when the electrons are far apart

article (http://physicsweb.org/articles/news/9/7/11/1)

cran
2005-Aug-20, 05:13 PM
okay... chalk one up for the Standard Model :)

jkmccrann
2005-Nov-05, 08:49 AM
an international collaboration of particle physicists has made new measurements that shed more light on the weak force, which is responsible for radioactive beta-decay.

The results, which agree with the Standard Model, show that the strength of the weak force acting on two electrons lessens when the electrons are far apart

article (http://physicsweb.org/articles/news/9/7/11/1)

Well surely that makes logical sense? If it was the other way around, wouldn't things be a little chaotic?

devilmech
2005-Nov-05, 09:32 AM
Well surely that makes logical sense? If it was the other way around, wouldn't things be a little chaotic?

It's been hypothesized for quite a while, almost since the weak force was discovered, but only now has it been show to be true through observation. Chalk one up for science =)

Eta C
2005-Nov-05, 10:19 PM
The problem in doing this measurement is that the weak force is, well, weak. Interactions between electrons are dominated by their electrical charge and the EM force. It's a very tricky experiment to isolate the part of the interaction carried by the weak force. Plenty of experiments have been done that validate the weak force's behavior in neutrino interactions, but then neutrinos only interact via the weak force which is why they interact so seldom. This experiment, while giving the expected result, was one that had to be done. After all, scientists don't take it as a matter of faith that the weak force should operate the same way for electrons as it does for neutrinos.

There is a force that gets stronger as the distance increases. The color force between quarks is weak close in, but grows in strength as the distance increases. This is partly due to the fact that the force carriers (gluons) also carry the color charge (as opposed to photons, which are electrically neutral). The weakening of the force at short distances is referred to as asymptotic freedom and was the subject of the 2004 Nobel in physics. (http://nobelprize.org/physics/laureates/2004/index.html)

Ken G
2005-Nov-06, 09:45 AM
There is an even more common force that increases with distance-- the spring force, or any force that arises from a harmonic potential. OK, that's cheating, it's not a particle force, though it certainly is a familiar force in macroscopic contexts. Note that none of these forces can increase for all distances, as jkmccrann points out.