When a gas is heated, in the new system there is nothing there to absorb the energy except the neutrons, which are all that is there. Each neutron making up the gas can temporarily store excess energy by jumping to an excited state. The surface of each neutron deforms into regions of alternate pulsations, or undulations, each region going in while its closest neighbors all go out, and vice versa.
The lines separating these regions are of two types, parallel to the equator or running through the poles. The situation is analogous to the surface of a vibrating drum. It is a variation of the situation of a vibrating string. The energy is stored in the vibration of the surface. When the surface absorbs energy, the number of regions increases, and larger and more complicated electron cloud patterns are produced around the nucleus. When the surface releases energy, the number of regions decreases, the electron cloud patterns collapse back down, and lines of brightness are produced in the spectrum.
Fig. 6. "Quantized attributes correspond to confined waveforms like
the spherical harmonics, whose vibrations are restricted to the surface of
a sphere." - - - - - "Quantum Reality," p. 103.
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