The UFO hovers above. The crowd rushes to escape as the ship’s doors open, emitting a bright green laser that pulls everything in its path up and into the spacecraft.
Once a thing of pure science fiction, physicists have now created a small-scale real-life tractor beam that can move tiny objects towards a source without physically touching them.
New York University physicists David Ruffner and David Grier set out to experiment with tractor beams after a Chinese research team concluded that using a single laser called a Bessel beam, it should be possible to move particles in a tractor beam manner.
The experiments proved too particular to return favourable results, so the physicists tried a different approach. They found that using two overlapping Bessel beams, it is possible to pull small particles (in this case 0.03 milimetre silica spheres) towards a source.
However, a larger scale model of this experiment would need too much energy to function. So for now, only small particles should feat an imending abduction.
[Phys.org]
