Can CP violation in kaon decays explain the dominance of matter over antimatter?

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The forum discussion centers on the role of CP violation in kaon decays as a potential explanation for the matter-antimatter asymmetry in the universe. The Fitch and Cronin experiment highlights CP violation in weak interactions, specifically in the decay channels of neutral kaons, including K → pi-plus + electron + antineutrino and K → pi-minus + positron + neutrino. Griffith's analysis indicates that if CP were conserved, these decay channels would occur with equal probability, yet a preference for the positron channel is observed. This preference raises questions about the implications of CP violation on the dominance of matter over antimatter, suggesting that while CP violation is crucial, the exact mechanisms remain unclear.

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sunrah
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The Fitch and Cronin experiment is put forward as one of the very few examples of CP violation in weak interactions and as a possible explanation for matter anti-matter asymmetry.
The decay channels are

K → 3 pions
K → pi-plus + electron + antineutrino
K → pi-minus + positron + neutrino

Of these the neutral kaons prefer to decay into the positron channel. Griffith's says that if CP weren't violated these last two decays would have an equal probability of happening. How can a preference for antimatter can be used to explain a dominance of matter? Also in the second decay an antineutrino is produced is this somehow less important in this respect than the positron?
 
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sunrah said:
Of these the neutral kaons prefer to decay into the positron channel. Griffith's says that if CP weren't violated these last two decays would have an equal probability of happening.
This paper gives a detailed analysis of the semileptonic decays, and shows that CP violation makes them unequal. (Eqs.(2.47-8))

sunrah said:
How can a preference for antimatter can be used to explain a dominance of matter? Also in the second decay an antineutrino is produced is this somehow less important in this respect than the positron?
To get the dominance of matter over antimatter, CP violation must be somehow involved, but the details remain shrouded in mystery. There is not an obvious connection with the kaon decays.

"The explanation of how you possibly can make more particles than antiparticles always leads in the end to some explanation that basically just states that you need to be able to somehow make more particles than antiparticles." - Sascha Vongehr
 
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