"Geometrical modification of quaternionic quantum mechanics"
math-ph/0702095. May be of interest to cosmologists. The paper is
based on the recent discovery of natural relativistic structure on
quaternions (V. Trifonov, "Natural geometry of nonzero quaternions" IJTP 46
(2007), to appear, DOI 10.1007/s10773-006-9234-9).

[Mod. note: repost corrects math-ph number at poster's request -- mjh]