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Witold Skiba

Publications and source records attributed to Witold Skiba.

71 records · Page 4Linked to original sources

Field Theory Tests for Correlators in the AdS/CFT Correspondence

The order g^2 radiative corrections to all 2- and 3-point correlators of the composite primary operators Tr X^k are computed in {\cal N} = 4 supersymmetric Yang-Mills theory with gauge group SU(N). Corrections are found to vanish for all N. For k=2 this is a consequence of known superconformal nonrenormalization theorems, and for general k the result confirms an N-to-infinity, fixed large g^2N supergravity calculation and further conjectures in hep-th/9806074. A 3-point correlator involving {\cal N} = 4 descendents of Tr X^2 is calculated, and its order g^2 contribution also vanishes, giving evidence for the absence of radiative corrections in correlators of descendent operators.

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Gauge Theories with Tensors from Branes and Orientifolds

We present brane constructions in Type IIA string theory for N=1 supersymmetric SO and Sp gauge theories with tensor representations using an orientifold 6-plane. One limit of these set-ups corresponds to N=2 theories previously constructed by Landsteiner and Lopez, while a different limit yields N=1 SO or Sp theories with a massless tensor and no superpotential. For the Sp-type orientifold projection comparison with the field theory moduli space leads us to postulate two new rules governing the stability of configurations of D-branes intersecting the orientifold. Lifting one of our configurations to M-theory by finding the corresponding curves, we re-derive the N=1 dualities for SO and Sp groups using semi-infinite D4 branes.

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Classification of the N=1 Seiberg-Witten Theories

We present a systematic study of N=1 supersymmetric gauge theories which are in the Coulomb phase. We show how to find all such theories based on a simple gauge group and no tree-level superpotential. We find the low-energy solution for the new theories in terms of a hyperelliptic Seiberg-Witten curve. This work completes the study of all N=1 supersymmetric gauge theories where the Dynkin index of the matter fields equals the index of the adjoint (mu=G), and consequently all theories for which mu<G.

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Duality in Sp and SO Gauge Groups from M Theory

We describe fivebrane configurations in M theory whose 4-d spacetime contains N=1 supersymmetric Sp or SO gauge fields and fundamentals of these groups. We show how field-theory dualities for Sp and SO groups can be derived using these fivebrane configurations in M theory.

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Dynamical Supersymmetry Breaking

We review mechanisms of dynamical supersymmetry breaking. Several observations that narrow the search for possible models of dynamical supersymmetry breaking are summarized. These observations include the necessary and sufficient conditions for supersymmetry breaking. The two conditions are based on non-rigorous arguments, and we show examples where they are too restrictive. Dynamical effects present in models with product gauge groups are given special attention.

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Confinement in N=1 SUSY Gauge Theories and Model Building Tools

We develop a systematic approach to confinement in N=1 supersymmetric theories. We identify simple necessary conditions for theories to confine without chiral symmetry breaking and to generate a superpotential non-perturbatively (s-confine). Applying these conditions we identify all N=1 theories with a single gauge group and no tree-level superpotential which s-confine. We give a complete list of the confined spectra and superpotentials. Some of these theories are of great interest for model building. We give several new examples of models which break supersymmetry dynamically.

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Self-Dual N=1 SUSY Gauge Theories

We present a large set of new self-dual N=1 SUSY gauge theories. Examples include SU(N) theories with tensors and SO(N) theories with spinors. Using these dualities as starting points, new non-trivial duals can be derived by higgsing the gauge group or by integrating out matter. General lessons that can be learned from these duals are: ``accidental" infrared symmetries play an important role in duality, many theories have more than one ``dual", and there seems to be no simple organizing pattern which relates duals of theories with different number of flavors.

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A Systematic Approach to Confinement in N=1 Supersymmetric Gauge Theories

We give necessary criteria for N=1 supersymmetric theories to be in a smoothly confining phase without chiral symmetry breaking and with a dynamically generated superpotential. Using our general arguments we find all such confining SU and Sp theories with a single gauge group and no tree level superpotential.

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Exact Results and Duality for SP(2N) SUSY Gauge Theories with an Antisymmetric Tensor

We study supersymmetric Sp(2N) gauge theories with matter in the antisymmetric tensor representation and F fundamentals. For F=6 we solve the theory exactly in terms of confined degrees of freedom and a superpotential. By adding mass terms we obtain the theories with F<6 which we find to exhibit a host of interesting non-perturbative phenomena: quantum deformed moduli spaces with N constraints, instanton-induced superpotentials and non-equivalent disjoint branches of moduli spaces. We find a simple dual for F=8 and no superpotential. We show how the F=4 and F=2 theories can be modified to break supersymmetry spontaneously and point out that the Sp(6) theory with F=6 may be very interesting for model builders.

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Supersymmetry Breaking Through Confining and Dual Theory Gauge Dynamics

We show that theories in the confining, free magnetic, and conformal phases can break supersymmetry through dynamical effects. To illustrate this, we present theories based on the gauge groups $SU(n)\times SU(4)\times U(1)$ and $SU(n) \times SU(5) \times U(1)$ with the field content obtained by decomposing an $SU(m)$ theory with an antisymmetric tensor and $m-4$ antifundamentals.

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More Dynamical Supersymmetry Breaking

In this paper we introduce a new class of theories which dynamically break supersymmetry based on the gauge group SU(n)xSU(3)xU(1) for even n. These theories are interesting in that no dynamical superpotential is generated in the absence of perturbations. For the example SU(4)xSU(3)xU(1) we explicitly demonstrate that all flat directions can be lifted through a renormalizable superpotential and that supersymmetry is dynamically broken. We derive the exact superpotential for this theory, which exhibits new and interesting dynamical phenomena. For example, modifications to classical constraints can be field dependent. We also consider the generalization to SU(n)xSU(3)xU(1) models (with even n>4). We present a renormalizable superpotential which lifts all flat directions. Because SU(3) is not confining in the absence of perturbations, the analysis of supersymmetry breaking is very different in these theories from the n=4 example. When the SU(n) gauge group confines, the Yukawa couplings drive the SU(3) theory into a regime with a dynamically generated superpotential. By considering a simplified version of these theories we argue that supersymmetry is probably broken.

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Signatures of Technicolor Models with the GIM Mechanism

We investigate the production and the decays of pseudo-Goldstone bosons (PGBs) predicted by technicolor theories with the GIM mechanism (TC-GIM). The TC-GIM models contain exotic fermion families that do not interact under weak $SU(2)$, but they do have color and hypercharge interactions. These fermions form PGBs, which are the lightest exotic particles in the TC-GIM models. The spectrum of PGBs consists of color octets, leptoquarks and neutral particles. The masses of leptoquarks and color octets depend on a free parameter - the scale of confining interactions. Characteristic for TC-GIM models is a very light (approx 1 GeV) neutral particle with anomalous couplings to gauge boson pairs. We show how current experiments constrain the free parameters of the models. The best tests are provided by the pp --> TT and e^+e^- --> P^0 gamma reactions. Experiments at LHC and NLC can find PGBs of TC-GIM models in a wide range of parameter space. However, TC-GIM models can be distinguished from other TC models only if several PGBs are discovered.

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Searching for the Scalar of the Strongly-Coupled Standard Model

We investigate decays of the scalar bound state present in the Abbott-Farhi model. We show that decays with photons in the final state may have large branching ratios. We also show that operators coupling the scalar particle to two photons or to a photon and a Z^0 are not seriously constrained by electroweak data, unlike other sectors of the Abbott-Farhi model.

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Constraining the Strongly-Coupled Standard Model Including a W' Isotriplet

We consider the Strongly-Coupled Standard Model (Abbott-Farhi model) including an isotriplet of W' vector bosons. First we calculate the corrections to the low-energy theory, which can be effectively summarized in terms of the parameters S, T and U. Then we use high- precision electroweak measurements to constrain the mass and couplings of the W'. The W' couplings are restricted to be unnaturally small, and we conclude that this model is no longer compelling as a theory of the electroweak interactions.

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