Two Spectra

        Two Spectra

            Here is the spectrum of visible light:

                        ROY G. BIV:

                        Red, Orange, Yellow, Green, Blue, Indigo, Violet.

            Indigo is a compromise color; included here for the relative pronunciability of “Biv”; but also to achieve a one-to-one matching with the spectrum of electromagnetic radiation:

                        Radio, Microwave, Infrared, Visible, Ultraviolet, X-Rays, Gamma Rays

            This suggests this matchup:

                        Red                  -                       Radio

                        Orange             -                       Microwave

                        Yellow             -                       Infrared

                        Green              -                       Visible

                        Blue                 -                       Ultraviolet

                        Indigo              -                       X-Rays

                        Violet              -                       Gamma Rays

            But there is another possibility. Visible light spans a doubling of frequencies, and violet has some resemblance to red. Perhaps colors cycle with electromagnetic frequency, just as pitch cycles with sound-wave frequency. Just as we have high C, perhaps we can have “high green” or “low yellow”. Actually the electromagnetic spectrum covers many octaves, so really you’d have “19 high green” and “26 low yellow” .