Schisma: Difference between revisions

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Strangely enough, subtracting 9/8 from 8/5 gives you 64/45 even in JI, so mentioning that is not needed.
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The '''schisma''', '''32805/32768''', is the difference between the [[Pythagorean comma]] and the [[syntonic comma]]. It is equal to ([[9/8]])<sup>4</sup>/([[8/5]]) and to ([[135/128]])/([[256/243]]) and also to ([[9/8]])<sup>3</sup>/([[64/45]]). Tempering it out gives a [[5-limit]] microtemperament called [[Schismatic family#Schismatic aka Helmholtz|schismatic, schismic or Helmholtz]], which if extended to larger subgroups leads to the [[schismatic family]] of temperaments.
The '''schisma''', '''32805/32768''', is the difference between the [[Pythagorean comma]] and the [[syntonic comma]]. It is equal to ([[9/8]])<sup>4</sup>/([[8/5]]) and to ([[135/128]])/([[256/243]]) and also to ([[9/8]])<sup>3</sup>/([[64/45]]). Tempering it out gives a [[5-limit]] microtemperament called [[Schismatic family#Schismatic aka Helmholtz|schismatic, schismic or Helmholtz]], which if extended to larger subgroups leads to the [[schismatic family]] of temperaments.
=== Mathematical observations ===
The schisma is the reason for why the greatly composite numbers 1048576 (2<sup>20</sup>) and 104976 (18<sup>4</sup>) look alike. The largest common power of two between these numbers is 2<sup>5</sup>, and when reduced by that, 1049760/1048576 becomes 32805/32768.


== See also ==
== See also ==

Revision as of 12:27, 19 January 2022

Interval information
Ratio 32805/32768
Factorization 2-15 × 38 × 5
Monzo [-15 8 1
Size in cents 1.953721¢
Name schisma
FJS name [math]\displaystyle{ \text{d}{-2}^{5} }[/math]
Special properties reduced,
reduced harmonic
Tenney norm (log2 nd) 30.0016
Weil norm (log2 max(n, d)) 30.0033
Wilson norm (sopfr(nd)) 59
Open this interval in xen-calc

The schisma, 32805/32768, is the difference between the Pythagorean comma and the syntonic comma. It is equal to (9/8)4/(8/5) and to (135/128)/(256/243) and also to (9/8)3/(64/45). Tempering it out gives a 5-limit microtemperament called schismatic, schismic or Helmholtz, which if extended to larger subgroups leads to the schismatic family of temperaments.

Mathematical observations

The schisma is the reason for why the greatly composite numbers 1048576 (220) and 104976 (184) look alike. The largest common power of two between these numbers is 25, and when reduced by that, 1049760/1048576 becomes 32805/32768.

See also