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On the calculation of covariant expressions for Dirac bilinears
European Physical Journal C: Particles and Fields, 2021 In this article, various approaches to calculate covariant expressions for the bilinears of Dirac spinors are presented. For this purpose, algebraic equations defining Dirac spinors are discussed.
M. A. Olpak, A. Özpineci
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Integration of Coupling Dirac Structures [PDF]
Pacific Journal of Mathematics, 2015 Coupling Dirac structures are Dirac structures defined on the total space of a fibration, generalizing hamiltonian fibrations from symplectic geometry, where one replaces the symplectic structure on the fibers by a Poisson structure.
Brahic, Olivier, Fernandes, Rui Loja
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Hermitian and Non-Hermitian Dirac-Like Cones in Photonic and Phononic Structures
Frontiers in Physics, 2022 Accidental degeneracy plays an important role in the generation of novel band dispersions. Photonic structures that exhibit an accidental Dirac-like conical dispersion at the center of the Brillouin zone can behave like a zero-index material at the Dirac-
Jie Luo, Jie Luo, Yun Lai
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Integration of Dirac-Jacobi structures [PDF]
Journal of Physics A: Mathematical and General, 2005 We study precontact groupoids whose infinitesimal counterparts are Dirac-Jacobi structures. These geometric objects generalize contact groupoids. We also explain the relationship between precontact groupoids and homogeneous presymplectic groupoids ...
Aïssa Wade +13 more
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Formal Deformations of Dirac Structures
Journal of Geometry and Physics, 2006 In this paper we set-up a general framework for a formal deformation theory of Dirac structures. We give a parameterization of formal deformations in terms of two-forms obeying a cubic equation. The notion of equivalence is discussed in detail.
Bayen +29 more
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Dirac structures of omni-Lie algebroids [PDF]
International Journal of Mathematics, 2011 Omni-Lie algebroids are generalizations of Alan Weinstein's omni-Lie algebras. A Dirac structure in an omni-Lie algebroid $\dev E\oplus \jet E$ is necessarily a Lie algebroid together with a representation on $E$.
Chen, Zhuo, Liu, Zhangju, Sheng, Yunhe
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Singular reduction of Dirac structures
Transactions of the American Mathematical Society, 2011 The regular reduction of a Dirac manifold acted upon freely and properly by a Lie group is generalized to a nonfree action.
Jotz, Madeleine +2 more
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Topological Dirac-vortex modes in a three-dimensional photonic topological insulator [PDF]
Nature CommunicationsRecently, topological Dirac-vortex modes in Kekulé-distorted photonic lattices have attracted broad interest and exhibited promising applications in robust photonic devices such as topological cavities, lasers, and fibers.
Bei Yan +10 more
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Research Paper: First Order Energy Near Dirac Points for Graphene and Carbon Nanotubes with Arbitrary Chirality [PDF]
فیزیک کاربردی ایران, 2023 The effective Hamiltonian describing indirect exchange interactions of type Ruderman- Kittel-Kasuya-Yosida [RKKY] between the magnetic impurities near the Dirac Points is based on the first-order energy.
Abbas Zarifi
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Communications in Mathematical Physics, 2022 We study complex Dirac structures, that is, Dirac structures in the complexified generalized tangent bundle. These include presymplectic foliations, transverse holomorphic structures, CR-related geometries and generalized complex structures. We introduce two invariants, the order and the (normalized) type.
Aguero, Dan, Rubio, Roberto||
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