Mathematical Foundations of Complex Tonality

Boland, J R and Hughston, L P. 2023. Mathematical Foundations of Complex Tonality. Journal of Mathematics and Music, ISSN 1745-9737 [Article] (In Press)

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Abstract or Description

Equal temperament, in which semitones are tuned in irrational ratios, is best seen as a serviceable compromise, sacrificing purity for flexibility. Just intonation, in which intervals are given by products of powers of 2, 3, and 5, is more natural, but of limited flexibility. We propose a new scheme in which ratios of Gaussian integers form the basis of an abstract tonal system. The tritone, so problematic in just temperament, given ambiguously by the ratios 45:32, 64:45, 36:25, 25:18, none satisfactory, is in our scheme represented by the complex ratio 1 + i : 1. The major and minor whole tones, given by intervals of 9/8 and 10/9, can each be factorized into products of complex semitones, giving us a major complex semitone 3/4 (1 + i) and a minor complex semitone 1/3 (3 + i). The perfect third, given by the interval 5/4 , factorizes into the product of a complex whole tone 1/2 (1 + 2i) and its complex conjugate. Augmented with these supplementary tones, the resulting scheme of complex intervals based on products of low powers of Gaussian primes leads naturally to the construction of a complete system of major and minor scales in all keys.

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tone systems, Pythagorean tuning, just intonation, equal temperament, rational numbers, Gaussian integers, Tristan chord, generalized musical intervals, mathematics and music

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19 June 2023Accepted
17 July 2023Published Online

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Date Deposited:

22 Jun 2023 14:09

Last Modified:

17 Jul 2023 15:26

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Yes, this version has been peer-reviewed.


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