M. Arik et V. Gabay, UNIFICATION OF GAUGE COUPLINGS IN A KALUZA-KLEIN THEORY WITH 2 INTERNAL MANIFOLDS, Physical review. D. Particles and fields, 49(10), 1994, pp. 5604-5605
We consider a Kaluza-Klein theory whose ground state is R4 X M X K, wh
ere M and K are compact, irreducible, homogeneous-internal manifolds.
This is compatible with the existence of the graviton, gauge fields, m
assless scalar fields and the absence of the cosmological constant, pr
ovided that M and K are odd dimensional, and a dimensionally continued
Euler form action whose dimension is the same as the dimension of M X
K is chosen. In such a theory, the gauge couplings g(M)2 and g(K)2 ar
e unified. For M X K = S2m+1 X S2k+1, g(M)2/g(K)2 = m/k.