Triple-slit experiment confirms reality is quantum - New Scientist

Triple-slit experiment confirms reality is quantum: ""The experiment is much harder than it might seem," says James Franson of the University of Maryland, Baltimore County, who was not involved in the study. "The slightest misalignment of the slits might produce errors."

Urbasi Sinha of the University of Waterloo in Ontario, Canada, and colleagues managed to do it by carving into a metal coating on a glass plate to make three equally spaced transparent slits, 30 micrometres wide and 100 micrometres apart. Then they used a laser to fire photons one at a time at the plate and recorded the pattern of light on the other side."