Physicists testing Nobel-winning theory

( -- Soeren Prell and a team of Iowa State University researchers are part of an international research team testing a theory that led to a share of the 2008 Nobel Prize in Physics for Japanese researchers Makoto Kobayashi and Toshihide Maskawa.

Prell, an Iowa State University associate professor of physics and astronomy, is part of the BaBar experiment at the U.S. Department of Energy's SLAC National Accelerator Laboratory in Menlo Park, Calif. Prell returned to Iowa State this summer after a year in California as BaBar's physics analysis coordinator.

The experiment is the work of nearly 500 collaborating physicists from 74 institutions and 10 countries. Other Iowa State researchers who have been part of the BaBar research team are James Cochran, an associate professor of physics and astronomy; H. Bert Crawley, a professor of physics and astronomy; W. Thomas Meyer, an adjunct research professor; and Eli Rosenberg, a professor of physics and astronomy who's currently on assignment with the U.S. Department of Energy.

"The central focus of the BaBar experiment is to study the differences between matter and antimatter," Prell said. "One of the big questions of the universe is, "Why is it made out of matter?"

At the time of the big bang, physicists say the explosion of energy should have created equal amounts of matter and antimatter. And they say whenever particles of matter and antimatter would have met they would have annihilated each other.

But the universe wasn't annihilated and it's full of matter. So how did matter come out so far ahead?

Physicists believe a small imbalance of matter over antimatter -- something like an extra particle of matter for every 10 billion antimatter particles -- led to our world. They call that imbalance an asymmetry.

In 1964 physicists discovered an asymmetry between matter and antimatter -- it's also known as a charge-parity violation -- in subatomic particles called kaons. Nobel-winners Kobayashi and Maskawa in 1972 developed a theory that attempted to explain those symmetry violations. Their idea called for the addition of three quarks to the Standard Model of particle physics, a theory that explains how subatomic particles interact via forces. Other researchers theorized that studies of B mesons (very short-lived subatomic particles) would help explain these broken symmetries.

The BaBar experiment in California, which completed operations earlier this year, has been called a "B factory" because the electron-positron collisions it produces are capable of creating more than a million B mesons every day. Since 1999 researchers have been studying the decay of those subatomic particles to confirm the Kobayashi-Maskawa theory.

They did and the presenters of the Nobel Prize took notice: "As late as 2001, the two particle detectors BaBar at Stanford, USA, and Belle at Tsukuba, Japan, both detected broken symmetries independently of each other," says the press release announcing the Nobel Prize in Physics. "The results were exactly as Kobayashi and Maskawa had predicted almost three decades earlier."

"We found a particle/anti-particle asymmetry," Prell said. "We found that B mesons and anti-B mesons behave differently."

But, Prell said the Kobayashi-Maskawa theory doesn't fully explain the existence of the universe. So, once data analysis of the BaBar experiment is concluded and another 100 or so scientific papers written (that's in addition to the 375 already written), Prell and other physicists will be moving to the higher-energy experiments made possible by the Large Hadron Collider at CERN, the European Organization for Nuclear Research near Geneva, Switzerland.

And what do these theories and tests of the subatomic world do for all of us?

"We're not solving the financial crisis or the energy crisis," Prell said. "But this will help us all to understand a little bit better where we come from. There are big questions behind this such as, 'Why is there a universe made of matter?'"


Provided by Iowa State University

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Nov 13, 2008
The universe can be explained by the repulsion of antimatter by matter. The experiment at CERN (ALPHA) and DAPNIA will soon determine if antigravity exists. There are several web sites relative to the test on antihydrogen.

Nov 17, 2008
Not sure why its relevant to this article Atomsview but since you mention it anti-gravity does exist and its effects are visible all over the universe.


Nov 17, 2008
...but i don't think that anti-gravity matter is anti-matter for the following reasons:-
o there would be occasional anihilations and we would see the characteristic radiation;
o there's probably enormously more anti-gravity matter than normal matter so the baryon asymmetry problem would still exist but the other way round;
o anti-gravity matter is not just the opposite of normal matter since it is repelled from itself as well.

Nov 17, 2008
DAPNIA and ALPHA (CERN) have a gravitational theory that shows that antimatter repells matter. This effect is called dark energy. This energy keeps matter and antimatter in separate areas of the universe, and therefore no annihilation. In addition the theory shows that antimatter attracts antimatter, so there are antimatter gallaxies.

Nov 17, 2008
I see. Got a link?

Nov 17, 2008
There are several links, use Google: antihydrogen gravity alpha dapnia. The math of the theory reconciles with Maxwell's equations and quantum physics. I cannot provide the manuscript because of copyright laws.

DAPNIA and ALPHA (CERN) have a gravitational theory that shows that antimatter repells matter. This effect is called dark energy. This energy keeps matter and antimatter in separate areas of the universe, and therefore no annihilation. In addition the theory shows that antimatter attracts antimatter, so there are antimatter gallaxies.

Nov 18, 2008
If hydrogen naturally rises here on Earth, how are they going to know if anti-hydrogen is rising because it's anti-matter or just because it has such a tiny mass?!

Also, if anti-matter repelled matter (other than like charges) then we wouldn't have a problem with it annihilating with matter.

Nov 18, 2008
Hydrogen rises on earth because it is lighter than air. The experiment on antihydrogen is done in a vacuum.

Gravity (antigravity) originates from atoms, not from individual particles. Annihilation occurs between two particles, one matter, and the other antimatter.

Nov 18, 2008
Don't individual particles have mass? Surely gravity orginates at whatever level has the mass, not just at atom level.

Nov 18, 2008
Tim, yes, that is the standard interpretation if you believe that sort of thing. Oddly enough, there is very little understanding in the realm of quantum gravity. Gravity is essentially ignored.

Atomsview, thanks for the insight, however, I would still expect hydrogen/anti-hydrogen to "expand" to fill the container regardless of earth's gravity or air pressure. You would need a source of artificial gravity - a centrifuge perhaps?

Nov 18, 2008
earls - you know what I believe

Nov 18, 2008
The new electromagnetic quantum theory of gravity originates from matter atoms and antimatter atoms, and the gravitation affects extend into space, including to individual particles. Antihydrogen atoms are expected to be repelled by earth's gravity. See Dapnia ALPHA (CERN).

Nov 18, 2008
OK I bet they aren't

Nov 18, 2008
There has not been a gravitional experiment on antimatter. DAPNIA wil be the first test. You may be surprised by the result!

Nov 18, 2008
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