1,068 research outputs found
Existence Theorems for Hairy Black Holes in su(N) Einstein-Yang-Mills theories
We establish the existence of hairy black holes in su(N) Einstein-Yang-Mills
theories, described by N-1 parameters, corresponding to the nodes of the gauge
field functions.Comment: 64 pages, latex2e, minor changes on the nature of the parameters,
version to appear in J. Math. Phy
Instability of hairy black holes in spontaneously-broken Einstein-Yang-Mills-Higgs systems
The stability of a new class of hairy black hole solutions in the coupled
system of Einstein-Yang-Mills-Higgs is examined, generalising a method
suggested by Brodbeck and Straumann and collaborators, and Volkov and Gal'tsov.
The method maps the algebraic system of linearised radial perturbations of the
various field modes around the black hole solution into a coupled system of
radial equations of Schr\"odinger type. No detailed knowledge of the black hole
solution is required, except from the fact that the boundary conditions at the
physical space-time boundaries (horizons) must be such so as to guarantee the
{\it finiteness} of the various expressions involved. In this way, it is
demonstrated that the above Schr\"odinger equations have bound states, which
implies the instability of the associated black hole solution.Comment: 8 pages, LATE
Infinitely Coloured Black Holes
We formulate the field equations for Einstein-Yang-Mills theory,
and find spherically symmetric black-hole solutions. This model may be
motivated by string theory considerations, given the enormous gauge symmetries
which characterize string theory. The solutions simplify considerably in the
presence of a negative cosmological constant, particularly for the limiting
cases of a very large cosmological constant or very small gauge field. The
situation of an arbitrarily small gauge field is relevant for holography and we
comment on the AdS/CFT conjecture in this light. The black holes possess
infinite amounts of gauge field hair, and we speculate on possible consequences
of this for quantum decoherence, which, however, we do not tackle here.Comment: 23 pages latex2e, two ps figures incorporate
On the Existence of Soliton and Hairy Black Hole Solutions of su(N) Einstein-Yang-Mills Theory with a Negative Cosmological Constant
We study the existence of soliton and black hole solutions of four-dimensional EinsteinâYangâMills theory with a negative cosmological constant. We prove the existence of non-trivial solutions for any integer N, with N â 1 gauge field degrees of freedom. In particular, we prove the existence of solutions in which all the gauge field functions have no zeros. For fixed values of the parameters (at the origin or event horizon, as applicable) defining the soliton or black hole solutions, if the magnitude of the cosmological constant is sufficiently large, then the gauge field functions all have no zeros. These latter solutions are of special interest because at least some of them will be linearly stable
D-particle Recoil Space Times and "Glueball" Masses
We discuss the properties of matter in a D-dimensional anti-de-Sitter-type
space time induced dynamically by the recoil of a very heavy
D(irichlet)-particle defect embedded in it. The particular form of the recoil
geometry, which from a world-sheet view point follows from logarithmic
conformal field theory deformations of the pertinent sigma-models, results in
the presence of both infrared and ultraviolet (spatial) cut-offs. These are
crucial in ensuring the presence of mass gaps in scalar matter propagating in
the D-particle recoil space time. The analogy of this problem with the
Liouville-string approach to QCD, suggested earlier by John Ellis and one of
the present authors, prompts us to identify the resulting scalar masses with
those obtained in the supergravity approach based on the Maldacena's
conjecture, but without the imposition of any supersymmetry in our case. Within
reasonable numerical uncertainties, we observe that agreement is obtained
between the two approaches for a particular value of the ratio of the two
cut-offs of the recoil geometry. Notably, our approach does not suffer from the
ambiguities of the supergravity approach as regards the validity of the
comparison of the glueball masses computed there with those obtained in the
continuum limit of lattice gauge theories.Comment: 16 pages LATEX, one LATEX figure incorporate
Monopole Black Hole Skyrmions
Charged black hole solutions with pion hair are discussed. These can be used
to study monopole black hole catalysis of proton decay. There also exist multi-
black hole skyrmion solutions with BPS monopole behavior.Comment: 16 pages including 6 figure
On the existence of dyons and dyonic black holes in Einstein-Yang-Mills theory
We study dyonic soliton and black hole solutions of the
Einstein-Yang-Mills equations in asymptotically anti-de Sitter space. We prove
the existence of non-trivial dyonic soliton and black hole solutions in a
neighbourhood of the trivial solution. For these solutions the magnetic gauge
field function has no zeros and we conjecture that at least some of these
non-trivial solutions will be stable. The global existence proof uses local
existence results and a non-linear perturbation argument based on the (Banach
space) implicit function theorem.Comment: 23 pages, 2 figures. Minor revisions; references adde
On the existence of conformally coupled scalar field hair for black holes in (anti-)de Sitter space
The Einstein-conformally coupled scalar field system is studied in the presence of a cosmological constant. We consider a massless or massive scalar field with no additional self-interaction, and spherically symmetric black hole geometries. When the cosmological constant is positive, no scalar hair can exist and the only solution is the Schwarzschildâde Sitter black hole. When the cosmological constant is negative, stable scalar field hair exists provided the mass of the scalar field is not too large
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