Rotations
- Complex numbers describes rotations in two-dimensions, and quaternions can be used to describe rotations in three dimensions. Is there a connection between octonions and rotations in four dimensions?
Clifford algebras
- Relate the octonions to Clifford algebras. Compare the (associative) Clifford algebra construction with the (nonassociative) Cayley-Dickson construction. Give combinatorial interpretations of both and see how they differ.
- Is the Cayley-Dickson construction associative up to plus or minus signs (up to reflection)?
Modeling cognition
- How are the (nonassociative) octonions relate to the (associative) split-biquaternions?
- Compare the learning three-cycle (for the quaternions) and Fano's plane (eightfold way) for the octonions.
- Is there a way that the octonions get identified with the reals? The eightsome = nullsome gets understood as a onesome? And the identification of nullsome with onesome is related to the field with one element. And we are left with exceptional Lie structures.
Readings
Facts about octonions
- John Baez, based on Dixon: The group of symmetries (or technically, "automorphisms") of the octonions is the exceptional group {$G_2$}, which contains {$SU(3)$}. To get {$SU(3)$}, we can take the subgroup of {$G_2$} that preserves a given unit imaginary octonion... say {$e_1$}.
Modeling with octonions
- The octonions can model the nonassociativity of perspectives.
- The Clifford algebra {$\textrm{Cl}_{0,7}$} with seven generators (squaring to {$-1$}) and {$2^7$} basis elements models the sevensome. The Clifford algebra {$\textrm{Cl}_{0,3}$}, the split-biquaternions, with three generators (squaring to {$-1$}) and {$2^3$} basis elements models the threesome. The octonions have three generators and eight basis elements.
Octonions, standard model and unification. 2023.
Notes