326 research outputs found
The Geometry of (Super) Conformal Quantum Mechanics
N-particle quantum mechanics described by a sigma model with an N-dimensional
target space with torsion is considered. It is shown that an SL(2,R) conformal
symmetry exists if and only if the geometry admits a homothetic Killing vector
whose associated one-form is closed. Further, the SL(2,R) can
always be extended to Osp(1|2) superconformal symmetry, with a suitable choice
of torsion, by the addition of N real fermions. Extension to SU(1,1|1) requires
a complex structure I and a holomorphic U(1) isometry .
Conditions for extension to the superconformal group D(2,1;\alpha), which
involve a triplet of complex structures and SU(2) x SU(2) isometries, are
derived. Examples are given.Comment: 23 pages harvmac. Conventions simplified; typos corrected; references
adde
Superconformal Multi-Black Hole Quantum Mechanics
The quantum mechanics of N slowly-moving charged BPS black holes in
five-dimensional supergravity is considered. The moduli space
metric of the N black holes is derived and shown to admit 4 supersymmetries. A
near-horizon limit is found in which the dynamics of widely separated black
holes decouples from that of strongly-interacting, near-coincident black holes.
This decoupling suggests that the quantum states supported in the near-horizon
moduli space can be interpreted as internal states of a single composite black
hole carrying all of the charge. The near-horizon theory is shown to have an
enhanced D(2,1;0) superconformal symmetry. Eigenstates of the Hamiltonian H of
the near-horizon theory are ill-defined due to noncompact regions of the moduli
space corresponding to highly redshifted near-coincident black holes. It is
argued that one should consider, instead of H eigenstates, eigenstates of , where K is the generator of special conformal transformations. The
result is a well-defined Hilbert space with a discrete spectrum describing the
N-black hole dynamics.Comment: 17 pages AMSLaTeX with JHEP.cls, using epsf.tex for 3 eps figures.
Typos corrected. References adde
Anti-de Sitter Fragmentation
Low-energy, near-horizon scaling limits of black holes which lead to string
theory on AdS_2 x S^2 are described. Unlike the higher-dimensional cases, in
the simplest approach all finite-energy excitations of AdS_2 x S^2 are
suppressed. Surviving zero-energy configurations are described. These can
include tree-like structures in which the AdS_2 x S^2 throat branches as the
horizon is approached, as well as disconnected AdS_2 x S^2 universes. In
principle, the black hole entropy counts the quantum ground states on the
moduli space of such configurations. In a nonsupersymmetric context AdS_D for
general D can be unstable against instanton-mediated fragmentation into
disconnected universes. Several examples are given.Comment: harvmac (uses epsf), 27 pages with 6 eps figure
Superconformal symmetry and hyperKaehler manifolds with torsion
The geometry arising from Michelson & Strominger's study of N=4B
supersymmetric quantum mechanics with superconformal D(2,1;alpha)-symmetry is a
hyperKaehler manifold with torsion (HKT) together with a special homothety. It
is shown that different parameters alpha are related via changes in potentials
for the HKT target spaces. For alpha not 0 or -1, we describe how each such HKT
4m-manifold M is derived from a space N of dimension 4m-4 which is quaternionic
Kaehler with torsion and carries an Abelian instanton.Comment: 16 page
Potential one-forms for hyperk\"ahler structures with torsion
It is shown that an HKT-space with closed parallel potential 1-form has
-symmetry. Every locally conformally hyperk\"ahler manifold
generates this type of geometry. The HKT-spaces with closed parallel potential
1-form arising in this way are characterized by their symmetries and an
inhomogeneous cubic condition on their torsion.Comment: 16 pages, Latex, no figure
Robust interferometer for the routing of light beams carrying orbital angular momentum
We have developed an interferometer requiring only minimal angular alignment for the routing of beams carrying orbital angular momentum. The MachâZehnder interferometer contains a Dove prism in each arm where each has a mirror plane around which the transverse phase profile is inverted. One consequence of the inversions is that the interferometer needs no alignment. Instead the interferometer defines a unique axis about which the input beam must be coupled. Experimental results are presented for the fringe contrast, reaching a maximum value of 93±1%
Superconformal Black Hole Quantum Mechanics
In recent work, the superconformal quantum mechanics describing D0 branes in
the AdS_2xS^2xCY_3 attractor geometry of a Calabi-Yau black hole with D4 brane
charges p^A has been constructed and found to contain a large degeneracy of
chiral primary bound states. In this paper it is shown that the asymptotic
growth of chiral primaries for N D0 branes exactly matches the
Bekenstein-Hawking area law for a black hole with D4 brane charge p^A and D0
brane charge N. This large degeneracy arises from D0 branes in lowest Landau
levels which tile the CY_3xS^2 horizon. It is conjectured that such a multi-D0
brane CFT1 is holographically dual to IIA string theory on AdS_2xS^2xCY_3.Comment: 8 page
Superconformal Multi-Black Hole Moduli Spaces in Four Dimensions
Quantum mechanics on the moduli space of N supersymmetric Reissner-Nordstrom
black holes is shown to admit 4 supersymmetries using an unconventional
supermultiplet which contains 3N bosons and 4N fermions. A near-horizon limit
is found in which the quantum mechanics of widely separated black holes
decouples from that of strongly-interacting, near-coincident black holes. This
near-horizon theory is shown to have an enhanced D(2,1;0) superconformal
symmetry. The bosonic symmetries are SL(2,R) conformal symmetry and SU(2)xSU(2)
R-symmetry arising from spatial rotations and the R-symmetry of N=2
supergravity.Comment: 23 pages, harvmac. v2: many typos fixe
Recommended from our members
Phase II Proof-of-Concept Trial of the Orexin Receptor Antagonist Filorexant (MK-6096) in Patients with Major Depressive Disorder.
BackgroundWe evaluated the orexin receptor antagonist filorexant (MK-6096) for treatment augmentation in patients with major depressive disorder.MethodsWe conducted a 6-week, double-blind, placebo-controlled, parallel-group, Phase II, proof-of-concept study. Patients with major depressive disorder (partial responders to ongoing antidepressant therapy) were randomized 1:1 to once-daily oral filorexant 10 mg or matching placebo.ResultsDue to enrollment challenges, the study was terminated early, resulting in insufficient statistical power to detect a prespecified treatment difference; of 326 patients planned, 129 (40%) were randomized and 128 took treatment. There was no statistically significant difference in the primary endpoint of change from baseline to week 6 in Montgomery Asberg Depression Rating Scale total score; the estimated treatment difference for filorexant-placebo was -0.7 (with negative values favoring filorexant) (P=.679). The most common adverse events were somnolence and suicidal ideation.ConclusionsThe interpretation of the results is limited by the enrollment, which was less than originally planned, but the available data do not suggest efficacy of orexin receptor antagonism with filorexant for the treatment of depression. (Clinical Trial Registry: clinicaltrials.gov: NCT01554176)
- âŠ