Waldyr Rodrigues formula for deSitter space

Waldyr says that for the deSitter O(4,1) group

Pa = -i{[1 - (r^2 - t^2)/R^2]^-1&a + (x^bMab/R^2)]}

Therefore, lim Pa as R -> infinity is i&a.

/\zpf = 1/R^2

OK, so what I meant was

D = dx^a(Pa/i)

as the GENERALIZED d for O(4,1)

This D^2 =/= 0 when /\zpf =/= 0

Limit of D when /\zpf ---> 0 is the Cartan d

Therefore, this D is analogous to a covariant exterior derivative with the extra stuff as a connection.