Beam me up, Scotty? NASA is funding projects to develop tractor beams. “Though a mainstay in science fiction, and Star Trek in particular, laser-based trapping isn’t fanciful or beyond current technological know-how”.
Three techniques are being considered. Optical tweezers use lasers to confine particles to the dark core of overlapping beams, then by altering the intensity of the beams heat the air around the particle and move it. This method requires an atmosphere and is already used by biophysicists to trap, move and extend individual DNA molecules, proteins or cells. A second method, optical solenoid beams , relies solely on electromagnetic effects and could operate in vacuum. Then there is the Bessel beam , still only theoretical and described poetically as ripples spreading from a pebble thrown in a pond. See the short video for explanation.