We analyze the mechanism of electroweak baryogenesis proposed by Farrar and Shaposhnikov in which the phase of the CKM mixing matrix is the only source of CP violation. This mechanism is based on a phase separation of baryons via the scattering of quasiparticles by the wall of an expanding bubble produced at the electroweak phase transition. In agreement with the recent work of Gavela, Hernández, Orloff and Pène, we conclude that QCD damping effects reduce the asymmetry produced to a negligible amount. We interpret the damping as quantum decoherence. We compute the asymmetry analytically. Our analysis reflects the observation that only a thin, outer layer of the bubble contributes to the coherent scattering of the quasiparticles. The generality of our arguments rules out any mechanism of electroweak baryogenesis that does not make use of a new source of CP violation.

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Recently, Jaffe and Manohar identified a new leading-twist structure function A(x,Q2), which can be measured in deep-inelastic scattering from polarized targets with spin 1 1. We calculate the scaling behavior of A(x,e2) in QCD, both by computing the anomalous dimensions of the associated operators and by finding the splitting function for the appropriate parton density. We also estimate the size of the lowest moment of A(x,Q2) in the bag model. In an appendix we give the complete cross section for electroproduction from a spin-1 target of arbitrary polarization.