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11.
It is shown that four-dimensional N=1N=1 supersymmetric QCD with massive flavors in the fundamental representation of the gauge group can be realized in the hidden sector of E8×E8E8×E8 heterotic string vacua. The number of flavors can be chosen to lie in the range of validity of the free-magnetic dual, using which one can demonstrate the existence of long-lived meta-stable non-supersymmetric vacua. This is shown explicitly for the gauge group Spin(10)Spin(10), but the methods are applicable to Spin(Nc)Spin(Nc), SU(Nc)SU(Nc) and Sp(Nc)Sp(Nc) for a wide range of color index NcNc. Hidden sectors of this type can potentially be used as a mechanism to break supersymmetry within the context of heterotic M-theory.  相似文献   
12.
Three-dimensional guidance in the neighborhood of collision course, based on a terminal differential game, renders ellipsoidal control sets. As a result, a saddle-point contains singularities. This paper (a) generalizes previous results on linear dynamics with terminal cost and ellipsoidal control sets and (b) applies the results to the above guidance problem to include general missile and target transfer functions. We further demonstrate the construction of the isocost surfaces (tubes).  相似文献   
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We consider in detail the most general cubic Lagrangian which describes an interaction between two identical higher spin fields in a triplet formulation with a scalar field, all fields having the same values of the mass. After performing the gauge fixing procedure we find that for the case of massive fields the gauge invariance does not guarantee the preservation of the correct number of propagating physical degrees of freedom. In order to get the correct number of degrees of freedom for the massive higher spin field one should impose some additional conditions on parameters of the vertex. Further independent constraints are provided by the causality analysis, indicating that the requirement of causality should be imposed in addition to the requirement of gauge invariance in order to have a consistent propagation of massive higher spin fields.  相似文献   
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We review the non-anticommutative Q-deformations of = (1, 1) supersymmetric theories in four-dimensional Euclidean harmonic superspace. These deformations preserve chirality and harmonic Grassmann analyticity. The associated field theories arise as a low-energy limit of string theory in specific backgrounds and generalize the Moyal-deformed supersymmetric field theories. A characteristic feature of the Q-deformed theories is the half-breaking of supersymmetry in the chiral sector of the Euclidean superspace. Our main focus is on the chiral singlet Q-deformation, which is distinguished by preserving the SO(4) ∼ Spin(4) “Lorentz” symmetry and the SU(2) R-symmetry. We present the superfield and component structures of the deformed = (1, 0) supersymmetric gauge theory as well as of hypermultiplets coupled to a gauge superfield: invariant actions, deformed transformation rules, and so on. We discuss quantum aspects of these models and prove their renormalizability in the Abelian case. For the charged hypermultiplet in an Abelian gauge superfield background we construct the deformed holomorphic effective action. The text was submitted by the authors in English.  相似文献   
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We consider the general gauge theory with a closed irreducible gauge algebra possessing the non-anomalous global (super)symmetry in the case when the gauge fixing procedure violates the global invariance of classical action. The theory is quantized in the framework of BRST-BV approach in the form of functional integral over all fields of the configuration space. It is shown that the global symmetry transformations are deformed in the process of quantization and the full quantum action is invariant under such deformed global transformations in the configuration space. The deformed global transformations are calculated in an explicit form in the one-loop approximation.  相似文献   
17.
We develop the superfield background field method and study the effective action in the N = 2, d3 supersymmetric Chern-Simons-matter systems. The one-loop low-energy effective action for non-Abelian supersymmetric Chern-Simons theory is computed to order F 4 by use of N = 2 superfield heat kernel techniques.  相似文献   
18.
A complete set of solutions of the Dirac equation is found in space-time with the metric ds2 = 2(d 2- dx2- dy2- dz2). For the Green's functions in$$ " align="middle" border="0"> and in$$ " align="middle" border="0"> , representations are found in the form of contour integrals from the Schwinger-De Witt nucleus over various contours.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 35–40, April, 1985.It remains to thank Yu. Yu. Vol'fengaut for discussions in the course of the present work.  相似文献   
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B. Pedemonte  O. Buchbinder 《ZDM》2011,43(2):257-267
In this paper, we analyze the role of examples in the proving process. The context chosen for this study was finding a general rule for triangular numbers. The aim of this paper is to show that examples are effective for the construction of a proof when they allow cognitive unity and structural continuity between argumentation and proof. Continuity in the structure is possible if the inductive argumentation is based on process pattern generalization (PPG), but this is not the case if a generalization is made on the results. Moreover, the PPG favors the development of generic examples that support cognitive unity and structural continuity between the argumentation and proof. The cognitive analysis presented in this paper is performed through Toulmin??s model.  相似文献   
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