16 research outputs found
Conformal Fixed Points of Unidentified Gauge Theories
In this article we discuss gauge/strings correspondence based on the
non-critical strings. With this goal we present several remarkable sigma models
with the AdS target spaces. The models have kappa symmetry and are completely
integrable. The radius of the AdS space is fixed and thus they describe
isolated fixed points of gauge theories in various dimensionsComment: 14 page
String theory as a universal language
This article, based on the Klein lecture, contains some new results and new
speculations on various topics. They include discussion of open strings in the
AdS space, unusual features of D-branes, conformal gauge theories in higher
dimensions. We also comment on the infrared screening of the cosmological
constant and on the "brane worlds"Comment: 19 page
Minimal Model Holography for SO(2N)
A duality between the large N 't Hooft limit of the WD_N minimal model CFTs
and a higher spin gravity theory on AdS3 is proposed. The gravity theory has
massless spin fields of all even spins s=2,4,6,..., as well as two real scalar
fields whose mass is determined by the 't Hooft parameter of the CFT. We show
that, to leading order in the large N limit, the 1-loop partition function of
the higher spin theory matches precisely with the CFT partition function.Comment: 21 pages, LaTe
Scalar Three-point Functions in a CDL Background
Motivated by the FRW-CFT proposal by Freivogel, Sekino, Susskind and Yeh, we
compute the three-point function of a scalar field in a Coleman-De Luccia
instanton background. We first compute the three-point function of the scalar
field making only very mild assumptions about the scalar potential and the
instanton background. We obtain the three-point function for points in the FRW
patch of the CDL instanton and take two interesting limits; the limit where the
three points are near the boundary of the hyperbolic slices of the FRW patch,
and the limit where the three points lie on the past lightcone of the FRW
patch. We expand the past lightcone three-point function in spherical
harmonics. We show that the near boundary limit expansion of the three-point
function of a massless scalar field exhibits conformal structure compatible
with FRW-CFT when the FRW patch is flat. We also compute the three-point
function when the scalar is massive, and explain the obstacles to generalizing
the conjectured field-operator correspondence of massless fields to massive
fields.Comment: 42 pages + appendices, 10 figures; v2, v3: minor correction
On the dynamical generation of the Maxwell term and scale invariance
Gauge theories with no Maxwell term are investigated in various setups. The
dynamical generation of the Maxwell term is correlated to the scale invariance
properties of the system. This is discussed mainly in the cases where the gauge
coupling carries dimensions. The term is generated when the theory contains a
scale explicitly, when it is asymptotically free and in particular also when
the scale invariance is spontaneously broken. The terms are not generated when
the scale invariance is maintained. Examples studied include the large
limit of the model in dimensions, a 3D gauged
vector model and its supersymmetric extension. In the latter case the
generation of the Maxwell term at a fixed point is explored. The phase
structure of the case is investigated in the presence of a Chern-Simons
term as well. In the supersymmetric model the emergence of the Maxwell
term is accompanied by the dynamical generation of the Chern-Simons term and
its multiplet and dynamical breaking of the parity symmetry. In some of the
phases long range forces emerge which may result in logarithmic confinement.
These include a dilaton exchange which plays a role also in the case when the
theory has no gauge symmetry. Gauged Lagrangian realizations of the 2D coset
models do not lead to emergent Maxwell terms. We discuss a case where the gauge
symmetry is anomalous.Comment: 38 pages, 4 figures; v2 slightly improved, typos fixed, references
added, published versio
Higher spin AdS_3 holography with extended supersymmetry
We propose a holographic duality between a higher spin AdS_3 gravity with
so(p) extended supersymmetry and a large N limit of a 2-dimensional
Grassmannian-like model with a specific critical level k=N and a non-diagonal
modular invariant. As evidence, we show the match of one-loop partition
functions. Moreover, we construct symmetry generators of the coset model for
low spins which are dual to gauge fields in the supergravity. Further, we
discuss a possible relation to superstring theory by noticing an N=3
supersymmetry of critical level model at finite k,N. In particular, we examine
BPS states and marginal deformations. Inspired by the supergravity side, we
also propose and test another large N CFT dual obtained as a Z_2 automorphism
truncation of a similar coset model, but at a non-critical level.Comment: 44 pages, published versio
Partition Functions of Holographic Minimal Models
The partition function of the W_N minimal model CFT is computed in the large
N 't Hooft limit and compared to the spectrum of the proposed holographic dual,
a 3d higher spin gravity theory coupled to massive scalar fields. At finite N,
the CFT contains additional light states that are not visible in the
perturbative gravity theory. We carefully define the large N limit, and give
evidence that, at N = infinity, the additional states become null and decouple
from all correlation functions. The surviving states are shown to match
precisely (for all values of the 't Hooft coupling) with the spectrum of the
higher spin gravity theory. The agreement between bulk and boundary is
partially explained by symmetry considerations involving the conjectured
equivalence between the W_N algebra in the large N limit and the higher spin
algebra of the Vasiliev theory.Comment: 56 page
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe