In 1905, Albert Einstein calculated that the speed of light remains at a constant 186,282 miles per second (299,792 km per second) when travelling through a vacuum. While this theory has been accepted for over a century, a controversial new study now suggests Einstein was in fact wrong
. Einstein claimed speed of light in a vacuum is 186,282 miles per second
. But James Franson from Maryland University believes it is slower than this
. In 1987, light particles of a supernova arrived 4.7 hours later than expected
. Dr James Franson suggests this may be because of ‘vacuum polarisation’
. This, he claims, had a gradual, but significant, impact on speed of photons
. If he is correct, it means scientists have to recalculate everything from our distance to the sun to some of the most distant objects in other galaxies
By Ellie Zolfagharifard
The study was conducted by Baltimore-based physicist, James Franson, who looked at why light particles of supernova SN 1987A arrived 4.7 hours later than expected.
The star’s collapse, which was seen from Earth in 1987, triggered a burst of neutrinos – an electrically neutral, weakly interacting elementary subatomic particle.
According to Einstein, this should have happened roughly three hours before a burst of optical light – and from that moment on, the pulses should have kept pace, both travelling at the speed of light.
However, the optical light arrived roughly 7.7 hours after the neutrinos – or 4.7 hours late.
HOW FAST IS THE SPEED OF LIGHT?
According to Albert Einstein, the speed of light remains at a constant 186,282 miles per second (299,792 km per second) when travelling through a vacuum.
In miles per hour, light speed is around 670,616,629 mph.
This means that a traveller, moving at the speed of light, would circumnavigate the equator 7.5 times in one second.
By comparison, a passenger in a jet aircraft, moving at a ground speed of 500 mph (800 km/hour), would cross the continental U.S. once in four hours.
The latest study suggests that the speed of light may be slower, but further research needs to be done to understand exactly how the delay is over vast distances.
According to Einstein, in theory nothing can travel faster than light…
