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CP violation explained by Kerr metric

  1. Jul 15, 2011 #1


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    This is an interesting hypothesis that doesn't seem to have been discussed yet. What are its flaws?

    Mark Hadley at the University of Warwick argues that galactic rotation causes gravitational frame-dragging sufficient to put a local asymmetric twist into spacetime and explain observed CP violations.

    If the universe was "spinning" early in the big bang, this could also have been the original source of CP violation to create the necessary matter~antimatter imbalance.

    His paper here...

    A gloss here....

    Some might connect it to Longo's axis of evil....

    It seems an elegantly simple explanation. I guess the whole early universe does not need to spin like a top (how can a boundaryless space rotate?) but there might be a fractal patchwork of spin orientations inside that added up to the needed total slight asymmetry.

    So what is wrong with the idea? (And what are your favourite alternative explanations for a source of CP violation?)
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  3. Jul 16, 2011 #2


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    There seems to be no explanation for different strength of CP-violation for different systems or elementary particles. The CKM-matrix (whereever it may come from - perhaps it is "induced" by some other effect) says that CP violation differs for different quarks. How can this be explained by a universal gravitational effect?

    That does not mean that the frame dragging idea is necessarily wrong; it would only mean that weak interaction and frame dragging are two different effects.
  4. Jul 16, 2011 #3
    The paper is very vague and the news article only makes it worse.

    It seems to me that there are three essential claims:

    - General relativity as we know it is grossly incomplete and the Einstein equation should be modified to include terms which fail to be conserved under P and T. We just didn't notice it yet, because the spacetime geometry is, locally, very nearly symmetric under T (and therefore CP). When he talks about the existence "an invariant scalar field, which quantifies the P and T asymmetry of the gravitational potential...acting oppositely on particles and antiparticles" on page 3, he really means that we need to modify the Einstein equation to include some weird coupling between matter and a new geometrical pseudotensor.

    - If this were the case, the strongest CP-violating effect in the vicinity of Earth would come from frame dragging due to galactic rotation.

    - We might be able to observe consequences of such CP-violation by looking at daily and yearly fluctuations in CP violation rates measured by particle accelerators.

    There's also one unjustified logic gap. The paper suggests to try to look for fluctuation in CP violation rates and at the same time tries to tie this idea into baryogenesis. This is called "trying to have your cake and eat it too."

    The statement in the beginning of the paper, "The standard model appears to correctly parameterise CP violation [in the CKM matrix] but it does not account for the origin of the effect. In any other branch of physics we would not be satisfied without an external explanation for any asymmetry", is, as far as I know, inaccurate. There's nothing magic or puzzling in the existence of CP violation via the CKM matrix. It comes in automatically as a free parameter in any model with more than two generations of quarks. It is this violation that we measure by looking at kaon oscillation & such.

    The problem wrt: baryogenesis is that the amount of CP violation we get out of the CKM matrix is some orders of magnitude too low. So there is another source somewhere out there, but we can't find it or measure it.

    So, the Kerr metric effect (if it exists) can either solve the problem of baryogenesis or be measurable at LHC, but there's no reason to think that it would do both at the same time.
  5. Jul 17, 2011 #4


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    Is the "loophole" here that the CKM-matrix lays down the basic coupling relations, but then the average temperature of the universe determines how close to relativistic all the particle interactions actually are? So you can get variations in the degree of CP violation that way. And if the early universe was violently churning, just by accident you would get sufficient violation to match the results we see.
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