The fate of four dimensions

  title={The fate of four dimensions},
  author={Steven B. Giddings},
  journal={Physical Review D},
  • S. Giddings
  • Published 4 March 2003
  • Physics
  • Physical Review D
In gravitational theories with extra dimensions, it is argued that the existence of a positive vacuum energy generically implies catastrophic instability of our four-dimensional world. The most generic instability is a decompactification transition to growth of the extra dimensions, although other equally bad transitions may take place. This follows from simple considerations based on the form of the potential for the size modulus of the extra dimensions, and apparently offers a resolution of… 
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