Submitted on 28 May 2006
Comment: AmSTeX, 36 pages, amsppt style
Subjects: Mathematics - Differential Geometry; Astrophysics; General Relativity and Quantum Cosmology; High Energy Physics - Phenomenology; High Energy Physics - Theory; Mathematical Physics; Quantum Physics; 81T20, 81V05, 81V10, 81V15, 81V17, 53A45