A US scientist claims to have found evidence that suggests that the speed of light as described by Einstein’s theory of general relativity is slower than has been thought. The theory of general relativity suggests light travels at 299,792,458 metres/second in a vacuum.
The claim by physicist James Franson of the University of Maryland claims to have found evidence that suggests the speed of light is actually slower than has been thought. Franson’s is based on observations made of the supernova SN 1987A, which exploded in 1987. Researchers on Earth picked up the arrival of both photons and neutrinos from the blast but The arrival of the photons was later than expected by 4.7 hours. Scientists at the time attributed it to a likelihood had said that this may be because the photons were from another source.
But what if that wasn’t what it was, Franson has proposed that this may actually be because light slows down as it travels due to a property of photons known as vacuum polarization – where a photon splits into a positron and an electron for a very short time before recombining back into a photon. That should create a gravitational differential, Franson noted, between the pair of particles, which would have a tiny energy impact when they recombine – enough to cause a slight bit of a slowdown during travel.
