Results 31 to 40 of about 259,006 (285)
Covariant Spin Structure [PDF]
, 1997 Every Dirac spin structure on a world manifold is associated with a certain gravitational field, and is not preserved under general covariant transformations. We construct a composite spinor bundle such that any Dirac spin structure is its subbundle, and
Gennadi A. Sardanashvily +1 more
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Tangent Dirac Structures and Poisson Dirac Submanifolds
Dhaka University Journal of Science, 2015 The local equations that characterize the submanifolds N of a Dirac manifold M is an isotropic (coisotropic) submanifold of TM endowed with the tangent Dirac structure. In the Poisson case which is a result of Xu: the submanifold N has a normal bundle which is a coisotropic submanifold of TM with the tangent Poisson structure if and only if N is a ...
MR Khan, MG M Talukder, Md Showkat Ali
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Differential operator Dirac structures
IFAC-PapersOnLine, 2021 As shown in earlier work, skew-adjoint linear differential operators, mapping efforts into flows, give rise to Dirac structures on a bounded spatial domain by a proper definition of boundary variables. In the present paper this is extended to pairs of linear differential operators defining a formally skew-adjoint relation between flows and efforts ...
van der Schaft, Arjan, Maschke, Bernhard
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Crystals, 2018 The optical conductivity in the charge order phase is calculated in the two-dimensional extended Hubbard model describing an organic Dirac electron system α -(BEDT-TTF) 2 I 3 using the mean field theory and the Nakano-Kubo formula ...
Daigo Ohki +3 more
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Multiplicative Dirac structures [PDF]
Pacific Journal of Mathematics, 2013 In this paper we introduce multiplicative Dirac structures on Lie groupoids, providing a unified framework to study both multiplicative Poisson bivectors (i.e., Poisson group(oid)s) and multiplicative closed 2-forms (e.g., symplectic groupoids). We prove that for every source simply connected Lie groupoid $G$ with Lie algebroid $AG$, there exists a one-
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Precessing anisotropic Dirac cone and Landau subbands along a nodal spiral
New Journal of Physics, 2013 We derive a three-dimensional Dirac-cone structure composed of tilted anisotropic Dirac cones around spirally located Dirac points. The Dirac points form a nodal spiral in momentum space due to accidental degeneracy, which can be realized in rhombohedral
C H Ho, C P Chang, W P Su, M F Lin
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Acoustic transport in higher-order topological insulators with Dirac hierarchy
New Journal of Physics, 2023 Dirac cones (DCs) are an important band structure in topological insulators (TIs) for realizing topological phase transition, and they provide unique ways to artificially regulate wave transport.
Xinglong Yu +11 more
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Manipulating type-I and type-II Dirac polaritons in cavity-embedded honeycomb metasurfaces [PDF]
, 2018 Pseudorelativistic Dirac quasiparticles have emerged in a plethora of artificial graphene systems that mimic the underlying honeycomb symmetry of graphene.
Barnes, William L. +4 more
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Dirac Clouds around Dilatonic Black Holes
Research, 2022 Dirac cloud is in absence in general relativity since the superradiance mechanism fails to work for Dirac fields. For the first time, we find a novel mechanism to support Dirac clouds, which is independent on superradiance mechanism.
Yang Huang, Hongsheng Zhang
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Visualizing near-coexistence of massless Dirac electrons and ultra-massive saddle point electrons
SciPost Physics, 2023 Strong singularities in the electronic density of states amplify correlation effects and play a key role in determining the ordering instabilities in various materials.
Abhay Kumar Nayak, Jonathan Reiner, Hengxin Tan, Huixia Fu, Henry Ling, Chandra Shekhar, Claudia Felser, Tamar (Tami) Pereg-Barnea, Binghai Yan, Haim Beidenkopf, Nurit Avraham
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