20 research outputs found
ABJ(M) and Fractional M2's with Fractional M2 Charge
Recently Aharony, Bergman and Jafferis (ABJ) have argued that a 3d
U(N+M)xU(N) Chern-Simons gauge theory at level (k,-k) may have a vacuum with
N=6 supersymmetry only if M<k+1 and if a certain period of the B-field in a IIA
background is quantized. We use a braneology argument to argue that N=3
supersymmetry may be preserved under the weaker condition that 2Nk>M(M-k)-1
with no restriction on the B-field. IIB brane cartoons and 11d supergravity
solutions corresponding to N=3 vacua that do not preserve N=6 supersymmetry are
argued to represent cascading gauge theories, generalizing the N=2 Seiberg
duality conjectured by Giveon and Kutasov. While as usual the M2-brane charge
runs as a result of the twisted Bianchi identity for *G_4, the M5-brane charge
running relies on the fact that it wraps a torsion homology cycle.Comment: 16 pages, 3 eps figure
ABJM models in N=3 harmonic superspace
We construct the classical action of the Aharony-Bergman-Jafferis-Maldacena
(ABJM) model in the N=3, d=3 harmonic superspace. In such a formulation three
out of six supersymmetries are realized off shell while the other three mix the
superfields and close on shell. The superfield action involves two
hypermultiplet superfields in the bifundamental representation of the gauge
group and two Chern-Simons gauge superfields corresponding to the left and
right gauge groups. The N=3 superconformal invariance allows only for a minimal
gauge interaction of the hypermultiplets. Amazingly, the correct sextic scalar
potential of ABJM emerges after the elimination of auxiliary fields. Besides
the original U(N)xU(N) ABJM model, we also construct N=3 superfield
formulations of some generalizations. For the SU(2)xSU(2) case we give a simple
superfield proof of its enhanced N=8 supersymmetry and SO(8) R-symmetry.Comment: 1+35 pages, minor changes, a reference added, published versio
N=2 solutions of massive type IIA and their Chern-Simons duals
We find explicit AdS4 solutions of massive type IIA with N=2 supersymmetry
obtained deforming with a Roman mass the type IIA supersymmetric reduction of
the M theory background AdS4 times M111. The family of solutions have SU(3)
times SU(3) structure and isometry SU(3) times U(1)^2. They are conjectured to
be dual to three-dimensional N=2 Chern-Simons theories with generic
Chern-Simons couplings and gauge group ranks.Comment: 20 pages, 1 figure, comments and references adde
Decoupling A and B model in open string theory -- Topological adventures in the world of tadpoles
In this paper we analyze the problem of tadpole cancellation in open
topological strings. We prove that the inclusion of unorientable worldsheet
diagrams guarantees a consistent decoupling of A and B model for open
superstring amplitudes at all genera. This is proven by direct microscopic
computation in Super Conformal Field Theory. For the B-model we explicitly
calculate one loop amplitudes in terms of analytic Ray-Singer torsions of
appropriate vector bundles and obtain that the decoupling corresponds to the
cancellation of D-brane and orientifold charges. Local tadpole cancellation on
the worldsheet then guarantees the decoupling at all loops. The holomorphic
anomaly equations for open topological strings at one loop are also obtained
and compared with the results of the Quillen formula
Brane Tilings and M2 Branes
Brane tilings are efficient mnemonics for Lagrangians of N=2
Chern-Simons-matter theories. Such theories are conjectured to arise on
M2-branes probing singular toric Calabi-Yau fourfolds. In this paper, a simple
modification of the Kasteleyn technique is described which is conjectured to
compute the three dimensional toric diagram of the non-compact moduli space of
a single probe. The Hilbert Series is used to compute the spectrum of
non-trivial scaling dimensions for a selected set of examples.Comment: 47 pages, 23 figure
N=2 supersymmetric AdS_4 solutions of M-theory
We analyse the most general N=2 supersymmetric solutions of D=11 supergravity
consisting of a warped product of four-dimensional anti-de-Sitter space with a
seven-dimensional Riemannian manifold Y_7. We show that the necessary and
sufficient conditions for supersymmetry can be phrased in terms of a local
SU(2)-structure on Y_7. Solutions with non-zero M2-brane charge also admit a
canonical contact structure, in terms of which many physical quantities can be
expressed, including the free energy and the scaling dimensions of operators
dual to supersymmetric wrapped M5-branes. We show that a special class of
solutions is singled out by imposing an additional symmetry, for which the
problem reduces to solving a second order non-linear ODE. As well as recovering
a known class of solutions, that includes the IR fixed point of a mass
deformation of the ABJM theory, we also find new solutions which are dual to
cubic deformations. In particular, we find a new supersymmetric warped AdS_4 x
S^7 solution with non-trivial four-form flux.Comment: 50 pages, 2 figures; v2: typos fixed, some intermediate formulas
added to improve clarity, references adde
Phases of M2-brane Theories
We investigate different toric phases of 2+1 dimensional quiver gauge
theories arising from M2-branes probing toric Calabi-Yau 4 folds. A brane
tiling for each toric phase is presented. We apply the 'forward algorithm' to
obtain the toric data of the mesonic moduli space of vacua and exhibit the
equivalence between the vacua of different toric phases of a given singularity.
The structures of the Master space, the mesonic moduli space, and the baryonic
moduli space are examined in detail. We compute the Hilbert series and use them
to verify the toric dualities between different phases. The Hilbert series,
R-charges, and generators of the mesonic moduli space are matched between toric
phases.Comment: 60 pages, 28 figures, 6 tables. v2: minor correction
A note on the holography of Chern-Simons matter theories with flavour
We study a three-dimensional N=3 U(N)_k x U(N)_{-k} Chern-Simons matter
theory with flavour, corresponding to the N=6
Aharony-Bergman-Jafferis-Maldacena CSM theory coupled to 2N_f fundamental
fields. The dual holographic description is given by the near-horizon geometry
of N M2-branes at a particular hypertoric geometry M_8. We explicitly construct
the space M_8 and match its isometries to the global symmetries of the field
theory. We also discuss the model in the quenched approximation by embedding
probe D6-branes in AdS_4 x CP^3.Comment: 21 pages, 3 figures, references added, minor changes (in particular
Fig. 2
Spin chain for the deformed ABJM theory
In this short note we begin the analysis of deformed integrable Chern-Simons
theories. We construct the two loop dilatation operator for the scalar sector
of the ABJM theory with and we compute the anomalous dimension of
some operators.Comment: 25 pages, 2 figures; references adde
Holographic nonlinear hydrodynamics from AdS/CFT with multiple/non-Abelian symmetries
We study viscous hydrodynamics of hot conformal field theory plasma with
multiple/non-Abelian symmetries in the framework of AdS/CFT correspondence,
using a recently proposed method of directly solving bulk gravity in derivative
expansion of local plasma parameters. Our motivation is to better describe the
real QCD plasma produced at RHIC, incorporating its U(1)^Nf flavor symmetry as
well as SU(2)_I non-Abelian iso-spin symmetry. As concrete examples, we choose
to study the STU model for multiple U(1)^3 symmetries, which is a sub-sector of
5D N=4 gauged SUGRA dual to N=4 Super Yang-Mills theory, capturing Cartan
U(1)^3 dynamics inside the full R-symmetry. For SU(2), we analyze the minimal
4D N=3 gauged SUGRA whose bosonic action is simply an Einstein-Yang-Mills
system, which corresponds to SU(2) R-symmetry dynamics on M2-branes at a
Hyper-Kahler cone. By generalizing the bosonic action to arbitrary dimensions
and Lie groups, we present our analysis and results for any non-Abelian plasma
in arbitrary dimensions.Comment: 37 pages, v3: errors corrected, reference added, JHEP versio