Measured redshift invariance of photon velocity
Abstract
We report the first direct photon velocity measurements for extragalactic objects. A fiberoptic, photon timeofflight instrument, optimized for relatively dim sources ($m 12$), is used to measure the velocity of visible photons emanating from galaxies and quasars. Lightspeed is found to be $3.00\pm0.03\times10^{8} \mathrm{m s}^{1}$, and is invariant, within experimental error, over the range of redshifts measured ($0\leq z\leq1.33$). This measurement provides additional validation of Einstein's theory of General Relativity (GR) and is consistent with the FriedmannLemaîtreRobertsonWalker (FLRW) metricl, as well as several alternative cosmological models, notably the hyperbolic antide Sitter metric, though not with the pseudoEuclidean de Sitter metric.
 Publication:

arXiv eprints
 Pub Date:
 December 2010
 arXiv:
 arXiv:1012.0871
 Bibcode:
 2010arXiv1012.0871M
 Keywords:

 Astrophysics  Cosmology and Extragalactic Astrophysics;
 Astrophysics  Instrumentation and Methods for Astrophysics
 EPrint:
 13 pages, 4 figures