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CPT does exchange particles with their antiparticles, so if there were a time direction associated with particles then it might make sense to say that, by CPT, the antiparticles would have to have the opposite time direction. But there's no time direction associated with particles. It doesn't even make sense to say that something is "going forward in time"; ...


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Yes, CPT is compatible with the idea that matter and antimatter are created at equal amounts. CPT is a basic theorem of quantum field theories, QFT:s. QED i a QFT and thus obeys CPT. The original QED is a theory of electrons, positrons and photons. In QCD, when a positron is produced an electron is produced at the same time (pair production). Likewise, when ...


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The most common explanation for the "matter-antimatter asymmetry of the Universe" is $\rm CP$ violation in interactions involving leptons. This scenario is usually called leptogenesis because it generates a net excess of leptons compared to anti-leptons. This $\rm CP$ violation is currently unconfirmed by experiment (though there is also not yet any evidence ...


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It is a non-perturbative effect because it is 1-loop exact. The triangle diagram is actually the least insightful method to think about this, in my opinion. The core of the matter is the anomaly of the chiral symmetry, which you can also, for example, calculate by the Fujikawa method examining the change of the path integral measure under the chiral ...



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