93 research outputs found
On deformed gauge theories and their string/M-theory duals
We present general formulae for the TsT transformation (T-duality, shift,
T-duality) of type II string backgrounds and open string boundary conditions.
The TsT transformation provides a systematic procedure to find string theory
duals of gauge theories with deformed products of fields in the lagrangian, and
the duals can be analyzed by using transformed D-brane probes. As examples
illustrating some features of the deformed theories, we consider the known
backgrounds dual to non-commutative, dipole and beta-deformed N=4 Super
Yang-Mills as well as new backgrounds dual to deformations of the recently
proposed N=6 Chern-Simons-matter theory living on multiple M2-branes on an
orbifold.Comment: 34 pages, 2 figures; typos corrected, references and clarifications
added; order of subsections changed, redundant solution in 6.3 removed;
published versio
Predictions for orientifold field theories from type 0' string theory
Two predictions about finite-N non-supersymmetric "orientifold field
theories" are made by using the dual type 0' string theory on C^3 / Z_2 x Z_2
orbifold singularity. First, the mass ratio between the lowest pseudoscalar and
scalar color-singlets is estimated to be equal to the ratio between the axial
anomaly and the scale anomaly at strong coupling, M_- / M_+ ~ C_- / C_+.
Second, the ratio between the domain wall tension and the value of the quark
condensate is computed.Comment: latex, 14 page
N=1 gauge superpotentials from supergravity
We review the supergravity derivation of some non-perturbatively generated
effective superpotentials for N=1 gauge theories. Specifically, we derive the
Veneziano-Yankielowicz superpotential for pure N=1 Super Yang-Mills theory from
the warped deformed conifold solution, and the Affleck-Dine-Seiberg
superpotential for N=1 SQCD from a solution describing fractional D3-branes on
a C^3 / Z_2 x Z_2 orbifold.Comment: LaTeX, iopart class, 8 pages, 3 figures. Contribution to the
proceedings of the workshop of the RTN Network "The quantum structure of
space-time and the geometric nature of fundamental interactions", Copenhagen,
September 2003; v2: published version with minor clarification
Beta, Dipole and Noncommutative Deformations of M-theory Backgrounds with One or More Parameters
We construct new M-theory solutions starting from those that contain 5 U(1)
isometries. We do this by reducing along one of the 5-torus directions, then
T-dualizing via the action of an O(4,4) matrix and lifting back to
11-dimensions. The particular T-duality transformation is a sequence of O(2,2)
transformations embedded in O(4,4), where the action of each O(2,2) gives a
Lunin-Maldacena deformation in 10-dimensions. We find general formulas for the
metric and 4-form field of single and multiparameter deformed solutions, when
the 4-form of the initial 11-dimensional background has at most one leg along
the 5-torus. All the deformation terms in the new solutions are given in terms
of subdeterminants of a 5x5 matrix, which represents the metric on the 5-torus.
We apply these results to several M-theory backgrounds of the type AdS_r x
X^{11-r}. By appropriate choices of the T-duality and reduction directions we
obtain analogues of beta, dipole and noncommutative deformations. We also
provide formulas for backgrounds with only 3 or 4 U(1) isometries and study a
case, for which our assumption for the 4-form field is violated.Comment: v2:minor corrections, v3:small improvements, v4:conclusions expanded,
to appear in Class. Quant. Gra
Producción innovadora y sustentable en un sistema acuapónico en la provincia de Buenos Aires
Esta experiencia se realizó en el Laboratorio de Acuicultura (U.A.MdP-UTN), el objetivo fue producir peces y vegetales reduciendo la tasa de recambio de agua y su descarte hacia el ambiente, resultando en un uso más sustentable. Esto se traduce en menores costos operativos del sistema, aumentando la rentabilidad productiva y beneficiando al medio ambiente. En nuestro país aún no se han implementado sistemas de producción de acuaponia con la especie Oreochromis niloticus (Tilapia del Nilo), lo cual lo hace más novedoso. Esta experiencia se realiza en un sistema de recirculación con un mínimo recambio de agua semanal. Los sistemas utilizados para el cultivo hidropónico son los denominados Sistema de Balsas y NFT (Nutrient Film Technique) y para los peces SRA (Sistema de Recirculación Acuícola). Como resultado se obtuvo un buen crecimiento de las hortalizas, cosechando cada 50 días hierbas aromáticas y ciboulette y cada 45 días verduras de hoja y tomates cherry; respecto a los peces se cosecharon a los tres meses ejemplares de 300gs. Como resultado se obtuvieron vegetales y pescado de muy buena calidad, fortalecido por parte de un panel de evaluación sensorial con una muy buena aceptación. En base a todo lo expuesto podemos concluir que este novedoso sistema de producción alternativo no solo es factible de realizar a pequeña escala, sino también extrapolarlo a mediana o mayor escala y en espacios de poca dimensión
A KK-monopole giant graviton in AdS_5 x Y_5
We construct a new giant graviton solution in AdS_5 x Y_5, with Y_5 a
quasi-regular Sasaki-Einstein manifold, consisting on a Kaluza-Klein monopole
wrapped around the Y_5 and with its Taub-NUT direction in AdS_5. We find that
this configuration has minimal energy when put in the centre of AdS_5, where it
behaves as a massless particle. When we take Y_5 to be S^5, we provide a
microscopical description in terms of multiple gravitational waves expanding
into the fuzzy S^5 defined as an S^1 bundle over the fuzzy CP^2. Finally we
provide a possible field theory dual interpretation of the construction.Comment: 11 pages, published versio
Weyl Anomaly in NonRelativistic CFTs
We study Weyl symmetry for non-relativistic conformal filed theories on
curved spatial spaces, and calculate it's quantum anomaly. We show that there
is no geometric anomaly, and the non-relativistic Weyl anomaly can appear only
due to interaction. Also we study the anomaly by using the light-cone approach.Comment: 10 pages, references added, conclusion correcte
Anomalies and Tadpoles in Open/Closed String Duality
We discuss the role played by the divergences appearing in the interaction
between a fractional D3 brane dressed with an SU(N) gauge field and a stack of
N fractional D3 branes on the orbifolds C^2/Z_2 and C^3/(Z_2 x Z_2). In
particular we show that the logarithmic divergences in the closed string
channel, interpreted as due to twisted massless tadpoles, are mapped, under
open/closed string duality, in the logarithmic ones in the open string channel,
due to the massless states circulating in the annulus diagram and corresponding
to the one-loop divergences that one finds in the gauge theory living in the
world volume of the brane. This result provides a quantitative evidence of why
the chiral and scale anomalies of the supersymmetric and non conformal gauge
theories supported by the world volume of the branes can be inferred from
supergravity calculations.Comment: LaTeX, 8 pages. Contribution to the proceedings of the workshop of
the RTN Network "The quantum structure of space-time and the geometric nature
of fundamental interactions", Copenhagen, September 200
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