4,697 research outputs found
A non-Abelian Black Ring
We construct a supersymmetric black ring solution of SU(2) N=1, d=5
Super-Einstein-Yang-Mills (SEYM) theory by adding a distorted BPST instanton to
an Abelian black ring solution of the same theory. The change cannot be
observed from spatial infinity: neither the mass, nor the angular momenta or
the values of the scalars at infinity differ from those of the Abelian ring.
The entropy is, however, sensitive to the presence of the non-Abelian
instanton, and it is smaller than that of the Abelian ring, in analogy to what
happens in the supersymmetric coloured black holes recently constructed in the
same theory and in N=2, d=4 SEYM. By taking the limit in which the two angular
momenta become equal we derive a non-Abelian generalization of the BMPV
rotating black-hole solution.Comment: 19 pages, no figure
One Thousand and One Bubbles
We propose a novel strategy that permits the construction of completely
general five-dimensional microstate geometries on a Gibbons-Hawking space. Our
scheme is based on two steps. First, we rewrite the bubble equations as a
system of linear equations that can be easily solved. Second, we conjecture
that the presence or absence of closed timelike curves in the solution can be
detected through the evaluation of an algebraic relation. The construction we
propose is systematic and covers the whole space of parameters, so it can be
applied to find all five-dimensional BPS microstate geometries on a
Gibbons-Hawking base. As a first result of this approach, we find that the
spectrum of scaling solutions becomes much larger when non-Abelian fields are
present. We use our method to describe several smooth horizonless multicenter
solutions with the asymptotic charges of three-charge (Abelian and non-Abelian)
black holes. In particular, we describe solutions with the centers lying on
lines and circles that can be specified with exact precision. We show the power
of our method by explicitly constructing a 50-center solution. Moreover, we use
it to find the first smooth five-dimensional microstate geometries with
arbitrarily small angular momentum.Comment: 33 pages. v2: typos correcte
N=2 Einstein-Yang-Mills' static two-center solutions
We construct bona fide one- and two-center supersymmetric solutions to N=2,
d=4 supergravity coupled to SU(2) non-Abelian vector multiplets. The solutions
describe black holes and global monopoles alone or in equilibrium with each
other and exhibit non-Abelian hairs of different kinds.Comment: 46 pages, 1 figure; v2 references adde
Non-Abelian black holes in string theory
We study a family of 5-dimensional non-Abelian black holes that can be
obtained by adding an instanton field to the well-known D1D5W Abelian black
holes. Naively, the non-Abelian fields seem to contribute to the black-hole
entropy but not to the mass due to their rapid fall-off at spatial infinity. By
uplifting the 5-dimensional supergravity solution to 10-dimensional Heterotic
Supergravity first and then dualizing it into a Type-I Supergravity solution,
we show that the non-Abelian fields are associated to D5-branes dissolved into
the D9-branes (dual to the Heterotic "gauge 5-branes") and that their
associated RR charge does not, in fact, contribute to the entropy, which only
depends on the number16 pages of D-strings and D5 branes and the momentum along
the D-strings, as in the Abelian case. These "dissolved" or "gauge" D5-branes
do contribute to the mass in the expected form. The correct interpretation of
the 5-dimensional charges in terms of the string-theory objects solves the
non-Abelian hair puzzle, allowing for the microscopic accounting of the
entropy. We discuss the validity of the solution when alpha prime corrections
are taken into account.Comment: Latex 2e file, 21 pages. A full appendix on alpha prime corrections
and the corresponding discussions have been added. The conclusions have
suffered minor changes. Version accepted in JHE
Exact charges from heterotic black holes
We derive exact relations to all orders in the expansion for the
charges of a bound system of heterotic strings, solitonic 5-branes and,
optionally, a Kaluza-Klein monopole. The expressions, which differ from those
of the zeroth-order supergravity approximation, coincide with the values
obtained when only the corrections of quadratic order in curvature are
included. Our computation relies on the consistency of string theory as a
quantum theory of gravity; the relations follow from the matching of the Wald
entropy with the microscopic degeneracy. In the heterotic frame, the
higher-curvature terms behave as delocalized sources that introduce a shift
between near-horizon and asymptotic charges. On the other hand, when described
in terms of lower-dimensional effective fields, the solution carries constant
charges over space which coincide with those of the asymptotic heterotic
fields. In addition, we describe why the Gauss-Bonnet term, which only captures
a subset of the relevant corrections of quadratic order in curvature, in some
cases succeeds to reproduce the correct value for the Wald entropy, while fails
in others.Comment: 32 pages; v2: references adde
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