Pyrotechnic Universe

  title={Pyrotechnic Universe},
  author={R. Kallosh and L. Kofman and Andrei Linde},
One of the central points of the ekpyrotic cosmological scenario based on Hor̆ava-Witten theory is that we live on a negative tension brane. However, the tension of the visible brane in HW theory, as well as in relevant cases of non-standard embedding, is positive. To make this scenario realistic one must solve the problem of the negative cosmological constant on the visible brane and fine-tune the bulk brane potential with an accuracy of 10−50. In terms of a canonically normalized scalar field… Expand

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