A brief introduction to Regular Temperament Theory: Difference between revisions

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Removed ref to geometric algebra. Included ref to multilinear algebra.
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These two extremes were well explored prior to RTT. What RTT did was open up a vast middle ground between JI and ET, where the number of generators is greater than one but less than the number of primes being approximated. These are called regular temperaments (RT). Only a very small region of that middle ground had been explored prior to RTT, namely the "[[meantone]]" region that approximates primes 2, 3 and 5, using two generators which are an octave (prime 2) and a slightly narrow fifth (approximate 2:3).
These two extremes were well explored prior to RTT. What RTT did was open up a vast middle ground between JI and ET, where the number of generators is greater than one but less than the number of primes being approximated. These are called regular temperaments (RT). Only a very small region of that middle ground had been explored prior to RTT, namely the "[[meantone]]" region that approximates primes 2, 3 and 5, using two generators which are an octave (prime 2) and a slightly narrow fifth (approximate 2:3).


When the generation of tunings is formulated in this way, the tools of linear algebra can be applied.<ref>or the slightly more powerful but less well-known and less available tools of a related algebra called exterior algebra, Grassman algebra or geometric algebra.</ref>
When the generation of tunings is formulated in this way, the tools of linear algebra can be applied.<ref>or our homegrown variety of multilinear algebra, which includes two copies of exterior algebra and uses an extended bra-ket notation, for which, unfortunately, tools are not readily available.</ref>


The defining thing about a regular temperament is the the count of each generator required to approximate each prime number.<ref>Strictly speaking, it is the [[Wedgies_and_Multivals|wedge product]] of the rows of the mapping matrix that defines the temperament, because you can replace any set of generators with linear combinations of those generators, and change the mapping accordingly, to obtain the same temperament.
The defining thing about a regular temperament is the the count of each generator required to approximate each prime number.<ref>Strictly speaking, it is the [[Wedgies_and_Multivals|wedge product]] of the rows of the mapping matrix that defines the temperament, because you can replace any set of generators with linear combinations of those generators, and change the mapping accordingly, to obtain the same temperament.