Scott,
Thanks for reading and commenting upon my essay. I'll answer your questions in order.
I do not think that space-time is fundamental, but I also do not think that space-time can be reduced to something more simple. I realize that this seems contradictory. I think that space-time is EMERGENT from actions upon the vacuum. IMO, that is the meaning of Equation 5.2. I took a pair of 5-D conjugates and multiplied them. The result was a scalar that is equal to the base quaternion's length.
I cannot comment upon how the Octonion Group compares to other mathematical interpretations since I have only recently begun to study Group Theory. I can state that the group includes anti-commutation between the complex i and the unit vectors. This is what makes the 5-D conjugates work. Space-time emerges from the vacuum. The vacuum is more fundamental than space-time and it is more complex than space-time. Therefore, I am arguing that simplicity emerges from complexity rather than the reverse argument:-)
Best Regards,
Gary Simpson