Global monopole in Kaluza-Klein spacetime

A class of static solution around a global monopole resulting from the breaking of a global SO(3) symmetry is obtained in a five-dimensional spacetime, whose three-dimensional usual space section is spherically symmetric. Depending on the choice of the arbitrary constants, the solutions may be shown to interpolate between a five-dimensional Schwarzschild-like solution with a singularity at the origin and a nonsingular solution representing a soliton. However, this nonsingular behaviour breaks down when viewed from an effective four-dimensional formalism. Analysis of null and time-like orbits in our spacetime reveals the existence of the trapping surfaces as well as repulsive barriers. This paper extends earlier work of Barriola and Vilenkin to its five-dimensional analogue and also a five-dimensional vacuum metric of Gross and Ferry through the inclusion of an external scalar field.