This movie shows one of the most beautiful – and mind-boggling –
experiments in physics: particles behaving as waves as they pass
through a diffraction grating. Each speck of light represents a
single molecule that has passed through the grating. If the
molecules obeyed the laws of classical physics – the laws that
describe the motion of everyday, macroscopic objects – we’d see
a pattern corresponding to the slits in the grating, as if we’d
thrown a load of blackcurrants through some railings (as you
do). Instead, we see an interference pattern, even though the
molecules go through the grating one by one. This can be
explained by each molecule having its own wavefront which goes
through all the slits at once – it’s a bit like a blackcurrant
turning into a wave (of Ribena?), rippling through all the
railings, and combining again into a blackcurrant as it hits the
wall. Crazy, I know. This phenomenon is called wave-particle
duality, and this movie is the first time it’s been captured on
camera for large molecul