Photons Collide to Create Matter

Since the dawn of the nuclear age, scientists have known how to generate light from matter. Now, a team of scientists at the Stanford Linear Accelerator Center has achieved the inverse: creating matter from light.
They collided large crowds of photons together from a high-power short-pulse laser that packs a half trillion watts of power into a beam measuring only 6 µm. To increase the photons' energy, the team collided the pulses with a 30µm-wide pulsed beam of high-energy electrons. The electron beam boosted photons to gamma energies and triggered interactions that resulted in matter and antimatter. The findings were reported in the Sept. 1 issue of the Physical Review Letters.