Photon race
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Glasgow researchers slow the speed of light

A team of Scottish scientists has made light rays travel slower than the speed of light.

Individual particles of light were sent through a mask that changed their shape and slowed them to less than light speed.

The photons continued to travel at the lower speed even when they returned to free space.

The experiment is likely to alter how science looks at light as BBC Scotland's science correspondent Kenneth Macdonald reports.

Follow @macdonke on Twitter to keep up with Ken's latest scientific musings.