A difference of differences.
By comparing two separate comparisons of matter and antimatter, researchers with the Belle detector may have found hints of new particles.
Credit: KEK
Posted on 03/26/2008 12:09:08 AM PDT by neverdem
A difference of differences.
By comparing two separate comparisons of matter and antimatter, researchers with the Belle detector may have found hints of new particles.
Credit: KEK
Why does the universe contain so much matter and so little antimatter? Particle physicists have puzzled over that question for 40 years. Now, new measurements may point to a hole in the current explanation for the subtle differences between matter and antimatter and could provide a better understanding of how the universe came to be chock-a-block with matter.
The key lies in a slight flaw in the mirrorlike relationship between matter (common particles such as protons and electrons) and antimatter (particles with identical masses but opposite charges). Dubbed charge-parity (CP) violation, the asymmetry was first seen in 1964 in the decays of fleeting particles called K mesons and their antimatter partners. In 1967, Russian theoretical physicist Andrei Sakharov suggested that CP violation might explain how, shortly after it sprang into existence, the infant universe produced so much matter and essentially no antimatter. Unfortunately, that scenario doesn't quite hang together. Through decades of experimentation, physicists have hammered together a "standard model" of the known particles, and it provides far too little CP violation to explain the imbalance.
Now, researchers have spotted an anomaly that might help square the accounts. It appeared in results from the Belle particle detector at the KEK laboratory in Tsukuba, Japan, where physicists measure the decays of a family of particles known as B mesons. The Belle team studied how a B ° meson decays into a K meson and a particle called a pion and compared it with how the B ° meson's antimatter partner decays into the corresponding antiparticles. As a result of CP violation, the decay rates were asymmetric. The researchers also studied the decay of a related particle called a B+ meson into a K meson and a pion and compared it with its antimatter counterpart. They observed a second asymmetry. Previous theoretical work suggested that the two asymmetries ought to be the same. They were not.
That discrepancy could indicate that undiscovered particles lurk inside B mesons in addition to the known mix of quarks and gluons, says team member Wei-Shu Hou, a physicist at National Taiwan University in Taipei. The interactions of such new particles could provide a bigger source of CP violation, which might ultimately help explain the preponderance of matter in the universe. Someday, "people may look back on the Belle measurement as the tip of the tip of the iceberg," Hou says.
Other researchers, however, say the results, published today in Nature, should be interpreted cautiously. It could all be an effect produced by run-of-the-mill particles, says Hassan Jawahery, a physicist at the University of Maryland, College Park and spokesperson for a group performing similar experiments at the Stanford Linear Accelerator Center in Menlo Park, California. Jawahery notes that his team has seen the same discrepancy, albeit with less statistical significance, and that the Belle measurements have been circulating for a while. "The result has been out for some time, and no one has been jumping to the conclusion that this is new physics," he says. Still, the finding raises that tantalizing possibility.
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“I’m givin’ ya full power already, Cap’n, I cann’a gi’ ya no more or I’ll melt the dilythium crystals!”
I love this type of science.
We smash two cars together, and try to figure out the nature of each piece, by photographing the sparks that come off the explosion.
Today’s physics is sounding more and more like Startrek.
Speaker of the House Tom Foley said it best,"No one has yet shown a shred of evidence that these rumors are true. Therefore, we must investigate further."
yitbos
Problem is that these scientists think that they have really said something about the Universe.
Reality is that they don’t know very much.
IMHO Unless they are trying to build a fusion reactor with this research, it is totally useless.
I once heard it described as “learning about Swiss watches by firing them into a brick wall with a cannon.”
Finding out about sub-sub-sub atomic particles is cool and all
But if it doesn’t get me pollution-free power or a 300mpg auto, why waste *my* hard earned dough on it?
IF it could lead to FTL travel, then maybe.
Physics ping!
How do you expect them to come up with those things, if they don't study stuff?
Magic?
Jet engine - marginal, they did pay for additional engineering work.
Atom bomb - yup, the FedGov did that one.
But you have to admit the Chia pet was privately funded.
I'll grant that most technology we use today had the FedGov as the midwife at least.
With Universities sitting on billions, maybe they could pony up more and hold the patents for selling any good tech that comes up.
(yes, I did my taxes today...)
YEC INTREP
Yankees win! Thaaaaaaaaaaaa Yankees WIN! 
This one works well for me.
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
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