Word: photonic
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...Einstein pointed out that an atom or molecule stimulated by an electro-magnetic wave (light, for example) would give off a basic unit of light called the photon, which would have the same wave length as the stimulating wave. A number of subsequent experiments proved Einstein correct. But not until 1958 did Physicists Arthur Schawlow and Charles Townes describe a device that they thought would be able to stimulate molecules of gas confined in a cylinder until they gave off photons in an intense and powerful stream. Their device was a variation of Townes's earlier Nobel Prizewinning invention...
...electricity is fired through the tube, it gives off a brief, intense flash of light. Inside the ruby rod, the chromium atoms are highly excited by the light flash; their electrons temporarily absorb excess energy. Then, as the electrons fall back toward their normal energy levels, each emits a photon. Some of the photons pass through the transparent walls of the ruby rod and are lost. But many hit the mirrors at either end of the rod and are reflected back to the opposite mirror. As they bounce back and forth along the rod, they stimulate other chromium atoms into...
...Kuppermann and White, this suggested that the wave length of light used in the previous exposure provided the minimum energy needed to cause the reaction. They then determined the energy carried by a photon at that wave length and calculated how much of it had been imparted to the deuterium atom when the deuterium iodide molecule was split. Their result: one-third of an electron volt...
Pouring out of the computer at 600 words per minute, the justified tape is passed into three Photon machines. Controlled by the holes in the tape, light passes through a whirling glass disk on which the alphabet is printed; letters are automatically selected and words recorded on photographic paper...
Such an experiment will be both expensive and difficult, and if it succeeds in bringing the theoretically expanding universe to a theoretical halt, it will raise an additional problem of its own: what happens to the energy lost in photon-photon collisions? Dr. Ward does not favor the suggestion that the lost energy turns into the radio waves that permeate space. He prefers the more startling notion that the energy is transformed, in some unexplained manner, into fresh, new hydrogen that provides an eternal source of nuclear fuel for the hydrogen-burning stars...