2,899 research outputs found
Adding new hair to the 3-charge black ring
Motivated by the string theory analysis of arXiv:1108.6331, we construct a
class of 1/8-BPS solutions of type IIB supergravity compactified on S^1 x T^4.
In this duality frame our ansatz allows for a non-trivial NS-NS B-field which
has been usually set to zero in previous studies of 1/8-BPS geometries. We
provide a M-theory description of these new geometries and show that they can
be interpreted as the lift of solutions of the N=2 5D supergravity with three
vector multiplets and whose scalar manifold is the symmetric space SO(1,1) x
(SO(1,2)/SO(2)). Finally we show that the non-minimal 5D black rings provide an
explicit example of solutions falling in this ansatz. In particular we point
out the existence of a black ring that has an extra dipole charge with respect
to the solutions of the STU-model. In the near-horizon limit, this ring has an
AdS_3 x S^3 geometry with the same radius as the one of the 3-charge black hole
and thus its microstates should belong to the usual D1-D5 CFT.Comment: 18 page
Perturbative superstrata
Issued under a Creative Commons Attribution LicenceS.G. has been partially supported by MIUR-PRIN contract 2009-KHZKRX, by the Padova University Project CPDA119349 and by INFN. R.R. has been partially supported by STFC Standard GrantST/J000469/1 âString Theory, Gauge Theory and Dualityâ
Non-extremal superdescendants of the D1D5 CFT
We construct solutions of IIB supergravity dual to non-supersymmetric states
of the D1D5 system. These solutions are constructed as perturbations carrying
both left and right moving momentum around the maximally rotating D1D5 ground
state at linear order. They are found by extending to the asymptotically flat
region the geometry generated in the decoupling limit by the action of left and
right R-currents on a known D1D5 microstate. The perturbations are regular
everywhere and do not carry any global charge. We also study the near-extremal
limit of the solutions and derive the first non-trivial correction to the
extremal geometry.Comment: 25 page
Superdescendants of the D1D5 CFT and their dual 3-charge geometries
We describe how to obtain the gravity duals of semiclassical states in the
D1-D5 CFT that are superdescendants of a class of RR ground states. On the
gravity side, the configurations we construct are regular and asymptotically
reproduce the 3-charge D1-D5-P black hole compactified on . The
geometries depend trivially on the directions but non-trivially on the
remaining 6D space. In the decoupling limit, they reduce to asymptotically
AdS spaces that are dual to CFT states obtained by
acting with (exponentials of) the operators of the superconformal algebra. As
explicit examples, we generalise the solution first constructed in
arXiv:1306.1745 and discuss another class of states that have a more
complicated dual geometry. By using the free orbifold description of the CFT we
calculate the average values for momentum and the angular momenta of these
configurations. Finally we compare the CFT results with those obtained in the
bulk from the asymptotically region.Comment: 50 pages; v2: corrected typos; v3: corrected typos, eq. (2.9b)
simplifie
Geometry of D1-D5-P bound states
Supersymmetric solutions of 6-d supergravity (with two translation
symmetries) can be written as a hyperkahler base times a 2-D fiber. The subset
of these solutions which correspond to true bound states of D1-D5-P charges
give microstates of the 3-charge extremal black hole. To understand the
characteristics shared by the bound states we decompose known bound state
geometries into base-fiber form. The axial symmetry of the solutions make the
base Gibbons-Hawking. We find the base to be actually `pseudo-hyperkahler': The
signature changes from (4,0) to (0,4) across a hypersurface. 2-charge D1-D5
geometries are characterized by a `central curve' ; the analogue for
3-charge appears to be a hypersurface that for our metrics is an orbifold of
.Comment: 20 pages, LaTeX; references adde
Branes wrapping Black Holes
We examine the dynamics of extended branes, carrying lower dimensional brane
charges, wrapping black holes and black hole microstates in M and Type II
string theory. We show that they have a universal dispersion relation typical
of threshold bound states with a total energy equal to the sum of the
contributions from the charges. In near-horizon geometries of black holes,
these are BPS states, and the dispersion relation follows from supersymmetry as
well as properties of the conformal algebra. However they break all
supersymmetries of the full asymptotic geometries of black holes and
microstates. We comment on a recent proposal which uses these states to explain
black hole entropy.Comment: 41 pages, 2 figures;v2: references adde
Session Types with Runtime Adaptation: Overview and Examples
In recent work, we have developed a session types discipline for a calculus
that features the usual constructs for session establishment and communication,
but also two novel constructs that enable communicating processes to be
stopped, duplicated, or discarded at runtime. The aim is to understand whether
known techniques for the static analysis of structured communications scale up
to the challenging context of context-aware, adaptable distributed systems, in
which disciplined interaction and runtime adaptation are intertwined concerns.
In this short note, we summarize the main features of our session-typed
framework with runtime adaptation, and recall its basic correctness properties.
We illustrate our framework by means of examples. In particular, we present a
session representation of supervision trees, a mechanism for enforcing
fault-tolerant applications in the Erlang language.Comment: In Proceedings PLACES 2013, arXiv:1312.221
6D microstate geometries from 10D structures
S.G. and L.M. have been partially supported by MIUR-PRIN contract 2009-KHZKRX, by the Padova University Project CPDA119349 and by INFN. R.R. has been partially supported by STFC Standard Grant ST/J000469/1 âString Theory, Gauge Theory and Dualityâ. S.G., M.P. and R.R. have been partially supported by the CNRS grant PICS âAspects of String Theory with Fluxes
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