Need Some Identities
- the algebraic ones ?
Identities are routinely used
to simplify or to reveal some underlying structures of mathematical expressions.
Because of the non-associative nature of octonions the non-trivial identities
involving three or more octonions draw greater interests. Here is a list
of few identities for octonions.
Let A, B, C, ...X, Y, represent
octonions.
(A, B, C) = - (A, C, B) =
(B, C,A) ,.... etc.,
i.e.,
skew symmetric in its three variables.
(X, X, A) = 0 = (X, A, X)
,.... etc.,
i.e., vanishes
whenever two variables are same.
(X, X*, A) = 0 = (X, X -1,
A) , where X*, and X -1
are conjugate and inverse of X, respectively.
(AB, C) - A (B, C) - (A, C) B
= 3 (A, B, C)
The next three identities are collectively known as Moufang
identities:
(XA, X, B) + (X, A, XB) = 0 ,
or ( ( XA) X) B - X (A(XB) ) = 0
(B, XA, X) = - (B, X, A) X ,
or B ( (XA) X ) = ( (BX) A ) X
(XA) (BX) = X (AB) X
(X 2 , A, B) =
X (X, A, B) + (X, A, B) X
( (X, Y, A) , X, Y) = -
(X, Y, A) (X, Y) = (X, Y) (X, Y, A)
( (X, Y, A)2 ,
X, Y) = 0 , Associative
law holds for some!
( (X, Y, A)2 ,
A) = 0 = ( (X, Y, A)4
, A) = 0 , Commutative
law holds for some!
|