People can detect flashes of light as feeble as a single photon, an experiment has demonstrated—a finding that seems to conclude a 70-year quest to test the limits of human vision.
The study, published in Nature Communications on July 19, “finally answers a long-standing question about whether humans can see single photons — they can!” says Paul Kwiat, a quantum optics researcher at the University of Illinois at Urbana–Champaign. The techniques used in the study also open up ways of testing how quantum properties—such as the ability of photons to be in two places at the same time—affect biology, he adds.
“The most amazing thing is that it’s not like seeing light. It’s almost a feeling, at the threshold of imagination,” says Alipasha Vaziri, a physicist at the Rockefeller University in New York City, who led the work and tried out the experience himself.To read more, click here.