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.
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 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
the physicist is correct, it means scientists have to recalculate
everything from our distance to the sun to some of the most distant
objects seen in other galaxies. Dr Franson’s paper has been submitted to
the New Journal of Physics and is currently undergoing peer review.