It seems the Universe has a sense of humour, as hot on the heels of the TEDx fiasco in which talks by Rupert Sheldrake and Graham Hancock were removed from YouTube, comes some scientific backing for one of Sheldrake's claims: that the speed of light may actually not be a constant, but vary:
Two forthcoming European Physical Journal D papers challenge established wisdom about the nature of vacuum. In one paper, Marcel Urban from the University of Paris-Sud, located in Orsay, France and his colleagues identified a quantum level mechanism for interpreting vacuum as being filled with pairs of virtual particles with fluctuating energy values. As a result, the inherent characteristics of vacuum, like the speed of light, may not be a constant after all, but fluctuate.
Meanwhile, in another study, Gerd Leuchs and Luis L. Sánchez-Soto, from the Max Planck Institute for the Physics of Light in Erlangen, Germany, suggest that physical constants, such as the speed of light and the so-called impedance of free space, are indications of the total number of elementary particles in nature.
Someone send the memo to Jerry Coyne...