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111.
Four Turyn type sequences of lengths 36, 36, 36, 35 are found by a computer search. These sequences give new base sequences of lengths 71, 71, 36, 36 and are used to generate a number of new T‐sequences. The first order of many new Hadamard matrices constructible using these new T‐sequences is 428. © 2004 Wiley Periodicals, Inc.  相似文献   
112.
《Discrete Mathematics》2019,342(5):1446-1455
In frequency-hopping spread spectrum systems, frequency-hopping sequences (FHSs) are widely used to alleviate the interferences caused by the hits of frequencies. In this paper, based on the Zeng–Cai–Tang–Yang cyclotomy and the Chinese Remainder Theorem, a family of FHS sets with composite lengths is constructed and the Hamming correlations of the new FHS sets are derived by some basic properties of cyclotomic numbers. The results show that the proposed FHS sets are optimal with respect to the Peng–Fan bound. Furthermore, it generalizes some earlier cyclotomic constructions of optimal FHS sets and produces optimal FHS sets with new parameters which are not covered in the literature.  相似文献   
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Lie Algebroid Yang–Mills theories are a generalization of Yang–Mills gauge theories, replacing the structural Lie algebra by a Lie Algebroid EE. In this note we relax the conditions on the fiber metric of EE for gauge invariance of the action functional. Coupling to scalar fields requires possibly nonlinear representations of Lie Algebroids. In all cases, gauge invariance is seen to lead to a condition of covariant constancy on the respective fiber metric in question with respect to an appropriate Lie Algebroid connection.  相似文献   
115.
The Dirac monopoles in 3-space and their generalization by C.N. Yang to 5-space are observed to be just the Levi-Civita spin connections of the cylindrical Riemannian metric on the 3-and 5-dimensional punctured spaces respectively. Their straightforward generalization to higher dimensions is also investigated.   相似文献   
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A rigorous algebraic proof of the full finiteness in all orders of perturbation theory is given for the Yang–Mills–Chern–Simons theory in a general three-dimensional Riemannian manifold. We show the validity of a trace identity, playing the role of a local form of the Callan–Symanzik equation, in all loop orders, which yields the vanishing of the -functions associated to the topological mass and gauge coupling constant as well as the anomalous dimensions of the fields.  相似文献   
118.
The purpose of this paper is to propose a noncommutative generalization of a gauge connection and the free-field Yang–Mills equations. The paper draws upon the techniques proposed by Heller et al. for the noncommutative generalization of the Einstein field equations.  相似文献   
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In this paper we present the Koopman‐von Neumann (KvN) formulation of classical non‐Abelian gauge field theories. In particular we shall explore the functional (or classical path integral) counterpart of the KvN method. In the quantum path integral quantization of Yang‐Mills theories concepts like gauge‐fixing and Faddeev‐Popov determinant appear in a quite natural way. We will prove that these same objects are needed also in this classical path integral formulation for Yang‐Mills theories. We shall also explore the classical path integral counterpart of the BFV formalism and build all the associated universal and gauge charges. These last are quite different from the analog quantum ones and we shall show the relation between the two. This paper lays the foundation of this formalism which, due to the many auxiliary fields present, is rather heavy. Applications to specific topics outlined in the paper will appear in later publications.  相似文献   
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