Light incoherence due to quantum-gravitational fluctuations of the
  background space
  Based on the theory of mutual coherence of light from an extended incoherent
quasi-monochromatic source (providing a basis of stellar interferometry) we
estimate the degree of light incoherence due to quantum-gravitational
fluctuations of the background metric. It is shown that the stellar
interferometry observational data considered in the literature for a last few
years as a manifestation against the Planck scale quantum-gravitational
fluctuations of the background metric have no chance for detecting such an
effect.
