Varying alpha in a more realistic Universe

  title={Varying alpha in a more realistic Universe},
  author={David F. Mota and John D. Barrow},
  journal={Physics Letters B},
Abstract We study the space–time evolution of the fine structure constant, α , inside evolving spherical overdensities in a lambda-CDM Friedmann universe using the spherical infall model. We show that its value inside virialised regions will be significantly larger than in the low-density background universe. The consideration of the inhomogeneous evolution of the universe is therefore essential for a correct comparison of extragalactic and solar system limits on, and observations of, possible… 

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