In addition to his work on set theory, Cohen has worked on differential equations and harmonic analysis.
You knew how to find just the right dreamlike quality for the music, whose harmonic language is neither tonal, nor modal, nor truly chromatic, but a little of all three at the same time.
For example, the Earth's magnetic field has a harmonic related to the Moon's daily variations, and also many other harmonics.
Their music, generally set for unaccompanied four-voice chorus, lacks the melodic and harmonic suavity of European music of the time.
In your own 5th harmonic chart you have two very close conjunctions, and some fairly close oppositions.
Thus, infrared photons at a I Am fundamental wavelength would produce a second harmonic signal in the green at 0.5 Am.
I find this house system the most revealing, because each house is a harmonic of the first house of the Self.
According to classical electromagnetic theory, a charge rotating with a simple harmonic frequency should emit electromagnetic radiation of the same frequency.
Moreover, it led me very directly to the periodogram, and to the study of forms of harmonic analysis more general than the classical Fourier series and Fourier integral.
His work in harmonic analysis has application in the theory of waves and vibrations.