Albert Einstein calculated that the speed of light remains at a constant 186,282 miles per second when traveling through a vacuum, in 1905. Baltimore-based physicist, James Franson, thinks otherwise. Simply put, he conducted a study that looked at why light particles of supernova SN 1987A arrived 4.7 hours later than expected. According to Einstein, this event should have occurred approximately 3-hours before a burst of optical light – and from that moment on, the pulses should have kept pace, both traveling at the speed of light. In reality, the optical light arrived roughly 7.7 hours after the neutrinos – or 4.7 hours late. Continue reading for a fascinating video and more information.

The Daily Mail reports:

“The University of Maryland physicist believes the delay could have been because the light was in fact slowed as it travelled due to something known as ‘vacuum polarisation’.

During this phenomenon, photons break down to something known as ‘positrons’ and electrons for a split second. before combining together again.

When they split, quantum mechanics creates a gravitational potential between the pair of ‘virtual’ particles.

Dr Franson argues that the process might have a gradual impact on the speed of the photon, meaning that over 168,000 light years, the photons may have suffered a near five-hour delay.