2 research outputs found
Cosmic Strings in the Abelian Higgs Model with Conformal Coupling to Gravity
Cosmic string solutions of the abelian Higgs model with conformal coupling to
gravity are shown to exist. The main characteristics of the solutions are
presented and the differences with respect to the minimally coupled case are
studied. An important difference is the absence of Bogomolnyi cosmic string
solutions for conformal coupling. Several new features of the abelian Higgs
cosmic strings of both types are discussed. The most interesting is perhaps a
relation between the angular deficit and the central magnetic field which is
bounded by a critical value.Comment: 22 pages, 10 figures; to appear in Phys. Rev.
Dilatonic global strings
We examine the field equations of a self-gravitating global string in low
energy superstring gravity, allowing for an arbitrary coupling of the global
string to the dilaton. Massive and massless dilatons are considered. For the
massive dilaton the spacetime is similar to the recently discovered
non-singular time-dependent Einstein self-gravitating global string, but the
massless dilaton generically gives a singular spacetime, even allowing for
time-dependence. We also demonstrate a time-dependent non-singular
string/anti-string configuration, in which the string pair causes a
compactification of two of the spatial dimensions, albeit on a very large
scale.Comment: 18 pages RevTeX, 3 figures, references amende