Weightlessness of photons: A quantum effect
  Contrary to general belief, the Fraunhofer lines have been found to be plasma redshifted and not gravitationally redshifted, when observed on Earth. Quantum mechanical effects cause the photons' gravitational redshift to be reversed as the photons move from the Sun to the Earth. The designs of the experiments, which were thought to have proven the gravitational redshift of photons, are all in the domain of classical physics, and make it impossible to detect the reversal of the gravitational redshifts. The solar redshift experiments, however, are in the domain of quantum mechanics; and the reversal of the redshift is easily detected, when the plasma redshift is taken into account. The photons are found to be weightless relative to a local observer, but repelled relative to a distant observer. The weightlessness of the photons in the gravitational field relative to a local observer is inconsistent with Einstein's equivalence principle. This together with the plasma redshift has profound consequences for the cosmological perspectives. This article gives a theoretical explanation of the observed phenomena, proper interpretation of the many gravitational redshift experiments, and an understanding of how we missed observing the reversal of photons' gravitational redshift. The present analysis indicates that although the photons are weightless in a local system of reference, the experimental evidence indicates that quasi-static electromagnetic fields are not weightless, but adhere to the principle of equivalence. 
Ari Brynjolfsson