symmetric monoidal (∞,1)-category of spectra
The octonions form the largest of the four normed division algebras, denoted .
A special triple or basic triple is a triple of three octonions such that
The choice of identifies an inclusion of the complex numbers .
Then the choice of on top of that identifies a compatible inclusion of the quaternions .
Finally the choice of on top of that induces a basis for all of .
(e.g. Baez, 4.1)
|Lorentzian spacetime dimension||spin group||normed division algebra||brane scan entry|
|the real numbers|
|the complex numbers|
|the quaternions||little string|
|the octonions||heterotic/type II string|
A survey is in
The concept of “special triples” or (“basic triples”) used above seems to go back to