Three Generations of Quarks are Needed To Avoid Anti-Matter
As we have already discussed, the reason we have particles without anti-particles is because of CP violation. CP-violation caused slightly more particles to be produced in the big bang then anti-particles. Then all the anti-particles annihilated with a particle leaving only the excess of particles we observe today.
However, it takes 3 generations of quarks to have CP violation. CP violation is encoded in the CKM Matrix, a 3 by 3 matrix. (N=3 for 3 generations of quarks). You need a overall phase in the CKM matrix to have cp-violation. If there were less then 3 generations of quarks, say 2, then the new 2 by 2 CKM matrix would have no overall phase and hence no CP-violation.
It was not too long ago when scientists had not suspected there were three generations of quarks. If there weren’t, we would have no CP-violation and no matter. It would have all been annihilated with the equal abundance of anti-matter.
By the way, in case you don’t know, the CKM matrix people won the Nobel Prize in physics last year.
Explore posts in the same categories: Physics, TheoryTags: Antimatter, CKM Matrix, CP violation, Matter, quarks
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May 29, 2009 at 6:38 pm
You have done a pretty good job summarizing the popular-bias consensus assumptions, however you’ve omitted to include the paradoxical aspects of these modern beliefs.
Paradox 1: Antimatter instability assumption is contradicted by concrete data showing that antihydrogen can be stored indefinitely within a vacuum.
Paradox 2: If instability occurred earliest on when particles were most exotic leading to random annihilations destroying “all” the antimatter, then this process statistically should be asymptotic. Hence, large annihilations SHOULD be visible in the cosmic record…but it is not.
Paradox 3: According to classic theory, “all” antimatter is gone. The giant antimatter cloud surrounding the supermassive black-hole at our galaxy’s center that was just mapped by NASA/ESA is a giant physical anomalous contradiction to this belief. http://www.esa.int/esaSC/SEMKTX2MDAF_index_0.html
Actually, there is a new theory set to replace CP-Violation that possesses none of these paradoxes. See the debate at http://hypography.com/forums/alternative-theories/18910-the-dominium-model-by-hasanuddin.html