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Technical question: vanishing of the cosmological constant in Randall Sundrum 1

  1. Jul 14, 2008 #1


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    This is a very technical question so I don't really expect someone to have the answer unless they have actually worked with or studied the RS models.

    They say that the value of the brane tensions in model 1 (which are related to the bulk cosmological constant) are such that the 4D cosmological constant (on our brane) is zero.
    I can't see how this comes about.

    I probably misunderstand but the way i see it, there are two contributions to the 4D cosmological constant: the brane tension itself plus the integral over the fifth dimension of the 5D cosmological constant. But when I do the integral, the two terms do not cancel out (there is a mismatch by a factor of 2). I could show my calculation but I will wait to see if anyone can help.

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  3. Jul 16, 2008 #2
  4. Jul 16, 2008 #3


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    Yes, this is a very good introduction. Unfortunately, it is not shown that the 4D cosmological constant in the original RS model is zero.

    The two original RS papers are




    If I recall, in the first one they don't say explicitly that the 4D cosmological constant is zero.
    In the second paper, they do say it and seem to imply that it follows trivially from the value of the brane tension and the constant appearing in the warp factor.
  5. Aug 4, 2008 #4
    I think they're just looking at Minkowski slices of AdS space, so the 4d cosmological constant is automatically 0.
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