966 research outputs found
The Thermodynamic Potentials of Kerr-AdS Black Holes and their CFT Duals
String or M-theory in the background of Kerr-AdS black holes is thought to be
dual to the large n limit of certain conformal field theories on a rotating
sphere at finite temperature. The five dimensional black hole is associated to
N=4 supersymmetric Yang-Mills theory on a rotating three-sphere and the four
dimensional one to the superconformal field theory of coinciding M2 branes on a
rotating two-sphere. The thermodynamic potentials can be expanded in inverse
powers of the radius of the sphere. We compute the leading and subleading terms
of this expansion in the field theory at one loop and compare them to the
corresponding supergravity expressions. The ratios between these terms at weak
and strong coupling turns out not to depend on the rotation parameters in the
case of N=4 SYM. For the field theory living on one M2 brane we find a
subleading logarithmic term. No such term arises from the supergravity
calculation.Comment: 14 pages (harvmac b-mode), signs corrected, minor changes otherwis
On Sp(0) factors and orientifolds
We discuss the geometric engineering of SO/Sp gauge theories with symmetric
or antisymmetric tensor matter and show that the `mysterious' rank zero gauge
group factors observed by a few authors can be traced back to the effects of an
orientifold which survives the geometric transition. By mapping the Konishi
constraints of such models to those of the U(N) theory with adjoint matter, we
show that the required shifts in the ranks of the unbroken gauge group
components is due to the flux contribution of the orientifold after the
transition.Comment: 14 page
Topological Strings from WZW Models
We show that the BRST structure of the topological string is encoded in the
``small'' superconformal algebra, enabling us to obtain, in a non-trivial
way, the string theory from hamiltonian reduction of . This leads to
the important conclusion that not only ordinary string theories, but
topological strings as well, can be obtained, or even defined, by hamiltonian
reduction from WZW models. Using two different gradations, we find either the
standard minimal models coupled to topological gravity, or an embedding
of the bosonic string into the topological string. We also comment briefly on
the generalization to super Lie algebras .Comment: 14p, late
Chiral field theories from conifolds
We discuss the geometric engineering and large n transition for an N=1 U(n)
chiral gauge theory with one adjoint, one conjugate symmetric, one
antisymmetric and eight fundamental chiral multiplets. Our IIB realization
involves an orientifold of a non-compact Calabi-Yau A_2 fibration, together
with D5-branes wrapping the exceptional curves of its resolution as well as the
orientifold fixed locus. We give a detailed discussion of this background and
of its relation to the Hanany-Witten realization of the same theory. In
particular, we argue that the T-duality relating the two constructions maps the
Z_2 orientifold of the Hanany-Witten realization into a Z_4 orientifold in type
IIB. We also discuss the related engineering of theories with SO/Sp gauge
groups and symmetric or antisymmetric matter.Comment: 34 pages, 8 figures, v2: References added, minor correction
Chiral field theories, Konishi anomalies and matrix models
We study a chiral N=1, U(N) field theory in the context of the Dijkgraaf-Vafa
correspondence. Our model contains one adjoint, one conjugate symmetric and one
antisymmetric chiral multiplet, as well as eight fundamentals. We compute the
generalized Konishi anomalies and compare the chiral ring relations they induce
with the loop equations of the (intrinsically holomorphic) matrix model defined
by the tree-level superpotential of the field theory. Surprisingly, we find
that the matrix model is well-defined only if the number of flavors equals two!
Despite this mismatch, we show that the 1/N expansion of the loop equations
agrees with the generalized Konishi constraints. This indicates that the matrix
model - gauge theory correspondence should generally be modified when applied
to theories with net chirality. We also show that this chiral theory produces
the same gaugino superpotential as a nonchiral SO(N) model with a single
symmetric multiplet and a polynomial superpotential.Comment: 43 page
Puzzles for Matrix Models of Chiral Field Theories
We summarize the field-theory/matrix model correspondence for a chiral N=1
model with matter in the adjoint, antisymmetric and conjugate symmetric
representations as well as eight fundamentals to cancel the chiral anomaly. The
associated holomorphic matrix model is consistent only for two fundamental
fields, which requires a modification of the original Dijkgraaf-Vafa
conjecture. The modified correspondence holds in spite of this mismatch.Comment: Contribution to the proceedings of the 36th International Symposium
Ahrenshoop, Berlin, August 26-30, 2003; 6 Page
(Anti)symmetric matter and superpotentials from IIB orientifolds
We study the IIB engineering of N=1 gauge theories with unitary gauge group
and matter in the adjoint and (anti)symmetric representations. We show that
such theories can be obtained as Z2 orientifolds of Calabi-Yau A2 fibrations,
and discuss the explicit T-duality transformation to an orientifolded
Hanany-Witten construction. The low energy dynamics is described by a geometric
transition of the orientifolded background. Unlike previously studied cases, we
show that the orientifold 5-`plane' survives the transition, thus bringing a
nontrivial contribution to the effective superpotential. We extract this
contribution by using matrix model results and compare with geometric data. A
Higgs branch of our models recovers the engineering of SO/Sp theories with
adjoint matter through an O5-`plane' T-dual to an O6-plane. We show that the
superpotential agrees with that produced by engineering through an O5-`plane'
dual to an O4-plane, even though the orientifold of this second construction is
replaced by fluxes after the transition.Comment: 40 page
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