Strings in cosmological and black hole backgrounds: Ring solutions

Journal Article · Sat Jan 15 00:00:00 EST 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.49.763· OSTI ID:5433833

de Vega, H J; Egusquiza, I L ^[1]

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1. Laboratoire de Physique Theorique et Hautes Energies, Universites Paris VI-VII, Laboratoire associe au Centre National de la Recherche Scientifique No. 280, Tour 16, 1er. etage 4, Place Jussieu, 75252 Paris Cedex 05 (France)

The string equations of motion and constraints are solved for a ring-shaped ansatz in cosmological and black hole spacetimes. In FRW universes with arbitrary power behavior [[ital R]([ital X][sup 0])=[ital a][vert bar][ital X][sup 0][vert bar][sup [alpha]]], the asymptotic form of the solution is found for both [ital X][sup 0][r arrow]0 and [ital X][sup 0][r arrow][infinity] and we plot the numerical solution for all times. Right after the big bang ([ital X][sup 0]=0), the string energy decreases as [ital R]([ital X][sup 0])[sup [minus]1] and the string size grows as [ital R]([ital X][sup 0]) for 0[lt][alpha][lt]1 and as [ital X][sup 0] for [alpha][lt]0 and [alpha][gt]1. Very soon [[ital X][sup 0][similar to]1], the ring reaches its oscillatory regime with frequency equal to the winding and constant size and energy. This picture holds for all values of [alpha] including string vacua (for which, asymptotically, [alpha]=1). In addition, an exact nonoscillatory ring solution is found. For black hole spacetimes (Schwarzschild, Reissner-Nordstroem, and stringy), we solve for ring strings moving towards the center. Depending on their initial conditions (essentially the oscillation phase), they are absorbed or not by Schwarzschild black holes. The phenomenon of particle transmutation is explicitly observed (for rings not swallowed by the hole). An effective horizon is noticed for the rings. Exact and explicit ring solutions inside the horizon(s) are found. They may be interpreted as strings propagating between the different universes described by the full black hole manifold.

• OSTI ID: 5433833
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 49:2; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BLACK HOLES
NUMERICAL SOLUTION
COSMOLOGICAL MODELS
STRING MODELS
RINGS
EQUATIONS OF MOTION
SCHWARZSCHILD METRIC
SPACE-TIME
COMPOSITE MODELS
DIFFERENTIAL EQUATIONS
EQUATIONS
EXTENDED PARTICLE MODEL
MATHEMATICAL MODELS
METRICS
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE MODELS
QUARK MODEL
662110* - General Theory of Particles & Fields- Theory of Fields & Strings- (1992-)