"It was like sci-fi really happening inside my own lab," said physicist Tomas Cizmar, describing the first tractor beam to pull an object with light, Star Wars-style. Normally, photons push matter away from a light source - picture the sun's rays pushing away a comet's tail. But Cizmar and colleagues at the Czech Institute of Scientific Instruments reported in January that they had figured out how to pull microscopic Styro-foam particles with light. They directed a laser beam through a lens and onto a mirror, which reflected back a second beam.
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