5,062 research outputs found
Conical Defects in Higher Spin Theories
We study conical defect geometries in the SL(N) Chern-Simons formulation of
higher spin gauge theories in AdS_3. We argue that (for N\geq 4) there are
special values of the deficit angle for which these geometries are actually
smooth configurations of the underlying theory. We also exhibit a gauge in
which these geometries can be viewed as wormholes interpolating between two
distinct asymptotically AdS_3 spacetimes. Remarkably, the spectrum of smooth
SL(N,C) solutions, after an appropriate analytic continuation, exactly matches
that of the so-called "light primaries" in the minimal model W_N CFTs at finite
N. This gives a candidate bulk interpretation of the latter states in the
holographic duality proposed in [1].Comment: 38 page
The Primary Spin-4 Casimir Operators in the Holographic SO(N) Coset Minimal Models
Starting from SO(N) current algebra, we construct two lowest primary higher
spin-4 Casimir operators which are quartic in spin-1 fields. For N is odd, one
of them corresponds to the current in the WB_{\frac{N-1}{2}} minimal model. For
N is even, the other corresponds to the current in the WD_{\frac{N}{2}} minimal
model. These primary higher spin currents, the generators of wedge subalgebra,
are obtained from the operator product expansion of fermionic (or bosonic)
primary spin-N/2 field with itself in each minimal model respectively. We
obtain, indirectly, the three-point functions with two real scalars, in the
large N 't Hooft limit, for all values of the 't Hooft coupling which should be
dual to the three-point functions in the higher spin AdS_3 gravity with matter.Comment: 65 pages; present the main results only and to appear in JHEP where
one can see the Appendi
Higher Spin Black Holes from CFT
Higher spin gravity in three dimensions has explicit black holes solutions,
carrying higher spin charge. We compute the free energy of a charged black hole
from the holographic dual, a 2d CFT with extended conformal symmetry, and find
exact agreement with the bulk thermodynamics. In the CFT, higher spin
corrections to the free energy can be calculated at high temperature from
correlation functions of W-algebra currents.Comment: 24 pages; v2 reference adde
Triality in Minimal Model Holography
The non-linear W_{\infty}[\mu] symmetry algebra underlies the duality between
the W_N minimal model CFTs and the hs[\mu] higher spin theory on AdS_3. It is
shown how the structure of this symmetry algebra at the quantum level, i.e. for
finite central charge, can be determined completely. The resulting algebra
exhibits an exact equivalence (a`triality') between three (generically)
distinct values of the parameter \mu. This explains, among other things, the
agreement of symmetries between the W_N minimal models and the bulk higher spin
theory. We also study the consequences of this triality for some of the
simplest W_{\infty}[\mu] representations, thereby clarifying the analytic
continuation between the`light states' of the minimal models and conical defect
solutions in the bulk. These considerations also lead us to propose that one of
the two scalar fields in the bulk actually has a non-perturbative origin.Comment: 29 pages; v2. Typos correcte
The Coset Spin-4 Casimir Operator and Its Three-Point Functions with Scalars
We find the GKO coset construction of the dimension 4 Casimir operator that
contains the quartic WZW currents contracted with completely symmetric SU(N)
invariant tensors of ranks 4, 3, and 2. The requirements, that the operator
product expansion with the diagonal current is regular and it should be primary
under the coset Virasoro generator of dimension 2, fix all the coefficients in
spin-4 current, up to two unknown coefficients. The operator product expansion
of coset primary spin-3 field with itself fixes them completely. We compute the
three-point functions with scalars for all values of the 't Hooft coupling in
the large N limit. At fixed 't Hooft coupling, these three-point functions are
dual to that found by Chang and Yin recently in the undeformed AdS_3 bulk
theory (higher spin gravity with matter).Comment: 65 pages; the ambiguity for the two coefficient functions is
clarified and the abstract, the introduction, the subsection 3.4 and the
conclusion are improved and to appear in JHE
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info:eu-repo/semantics/publishedVersio
The Large N 't Hooft Limit of Kazama-Suzuki Model
We consider N=2 Kazama-Suzuki model on CP^N=SU(N+1)/SU(N)xU(1). It is known
that the N=2 current algebra for the supersymmetric WZW model, at level k, is a
nonlinear algebra. The N=2 W_3 algebra corresponding to N=2 was recovered from
the generalized GKO coset construction previously. For N=4, we construct one of
the higher spin currents, in N=2 W_5 algebra, with spins (2, 5/2, 5/2, 3). The
self-coupling constant in the operator product expansion of this current and
itself depends on N as well as k explicitly. We also observe a new higher spin
primary current of spins (3, 7/2, 7/2, 4). From the behaviors of N=2, 4 cases,
we expect the operator product expansion of the lowest higher spin current and
itself in N=2 W_{N+1} algebra. By taking the large (N, k) limit on the various
operator product expansions in components, we reproduce, at the linear order,
the corresponding operator product expansions in N=2 classical
W_{\infty}^{cl}[\lambda] algebra which is the asymptotic symmetry of the higher
spin AdS_3 supergravity found recently.Comment: 44 pages; the two typos in the first paragraph of page 23 corrected
and to appear in JHE
Unitarity Bounds in AdS_3 Higher Spin Gravity
We study SL(N,R) Chern-Simons gauge theories in three dimensions. The choice
of the embedding of SL(2,R) in SL(N,R), together with asymptotic boundary
conditions, defines a theory of higher spin gravity. Each inequivalent
embedding leads to a different asymptotic symmetry group, which we map to an
OPE structure at the boundary. A simple inspection of these algebras indicates
that only the W_N algebra constructed using the principal embedding could admit
a unitary representation for large values of the central charge.Comment: 1+23 pages, Version 3 Appendix B revise
Symmetries of Holographic Super-Minimal Models
We compute the asymptotic symmetry of the higher-spin supergravity theory in
AdS_3 and obtain an infinite-dimensional non-linear superalgebra, which we call
the super-W_infinity[lambda] algebra. According to the recently proposed
supersymmetric duality between higher-spin supergravity in an AdS_3 background
and the 't Hooft limit of the N=2 CP^n Kazama-Suzuki model on the boundary,
this symmetry algebra should agree with the 't Hooft limit of the chiral
algebra of the CFT, SW_n. We provide two nontrivial checks of the duality. By
comparing the algebras, we explicitly match the lowest-spin commutation
relations in the super-W_infinity[lambda] with the corresponding commutation
relations in the 't Hooft limit on the CFT side. We also consider the
degenerate representations of the two algebras and find that the spectra of the
chiral primary fields are identical.Comment: 33 pages, references added, some errors corrected, discussions about
the truncation of the shs[lambda] algebra and reobtaining the original
shs[lambda] algebra from the super-W_infinity[lambda] algebra adde
Limits of minimal models and continuous orbifolds
The lambda=0 't Hooft limit of the 2d W_N minimal models is shown to be
equivalent to the singlet sector of a free boson theory, thus paralleling
exactly the structure of the free theory in the Klebanov-Polyakov proposal. In
2d, the singlet sector does not describe a consistent theory by itself since
the corresponding partition function is not modular invariant. However, it can
be interpreted as the untwisted sector of a continuous orbifold, and this point
of view suggests that it can be made consistent by adding in the appropriate
twisted sectors. We show that these twisted sectors account for the `light
states' that were not included in the original 't Hooft limit. We also show
that, for the Virasoro minimal models (N=2), the twisted sector of our orbifold
agrees precisely with the limit theory of Runkel & Watts. In particular, this
implies that our construction satisfies crossing symmetry.Comment: 33 pages; v2: minor improvements and references added, published
versio
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