ZhETF, Vol. 124,
No. 1,
p. 5 (July 2003)
(English translation  JETP,
Vol. 97, No. 1,
p. 1,
July 2003
available online at www.springer.com
)
MULTIDIMENSIONAL GLOBAL MONOPOLE AND NONSINGULAR COSMOLOGY
Bronnikov K.A., Meierovich B.E.
Received: January 20, 2003
PACS: 04.90.+e
We consider a spherically symmetric global monopole in general relativity in (D=d+2)dimensional spacetime. For γ < d1, where γ is a parameter characterizing the gravitational field strength, the monopole is shown to be asymptotically flat up to a solid angle defect. In the range d1< γ < 2d(d+1)/(d+2), the monopole spacetime contains a cosmological horizon. Outside the horizon, the metric corresponds to a cosmological model of the KantowskiSachs type, where spatial sections have the topology \R\times \S^{d}. In the important case where the horizon is far from the monopole core, the temporal evolution of the KantowskiSachs metric is described analytically. The KantowskiSachs spacetime contains a subspace with a (d+1)dimensional FriedmannRobertsonWalker metric, whose possible cosmological application is discussed. Some estimates in the d=3 case show that this class of nonsingular cosmologies can be viable. In particular, the symmetrybreaking potential at late times can give rise to both dark matter and dark energy. Other results, generalizing those known in the 4dimensional spacetime, are derived, in particular, the existence of a large class of singular solutions with multiple zeros of the Higgs field magnitude.

