sentences:  Optical levitation
  
  Optical levitation is a method developed by Arthur Ashkin whereby a material is levitated against the downward force of gravity by counter forces stemming from photon momentum transfer.Typically photon radiation pressure of a focused laser beam of enough intensity counters the downward force of gravity while also preventing lateral (side to side) and vertical instabilities to allow for a stable "optical trap" capable of holding small particles in suspension.