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Pseudo-Dirac structures

by David Li-bland , 2014
"... A Dirac structure is a Lagrangian subbundle of a Courant algebroid, L ⊂ E, which is involutive with respect to the Courant bracket. In particular, L inherits the structure of a Lie algebroid. In this paper, we introduce the more general notion of a pseudo-Dirac structure: an arbitrary subbundle, W ..."
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A Dirac structure is a Lagrangian subbundle of a Courant algebroid, L ⊂ E, which is involutive with respect to the Courant bracket. In particular, L inherits the structure of a Lie algebroid. In this paper, we introduce the more general notion of a pseudo-Dirac structure: an arbitrary subbundle

Pseudo-Dirac Neutrinos

by Darwin Chang, Otto C. W. Kong , 1999
"... We propose a scheme in which a pseudo-Dirac structure for three family of light neutrinos is generated naturally. An extended Higgs sector with a majoron is used for the generation of the leptonic number violating neutrino Majorana mass. The resultant neutrino mass matrix could easily fit all availa ..."
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We propose a scheme in which a pseudo-Dirac structure for three family of light neutrinos is generated naturally. An extended Higgs sector with a majoron is used for the generation of the leptonic number violating neutrino Majorana mass. The resultant neutrino mass matrix could easily fit all

Pseudo-Dirac solar neutrinos

by Yosef Nir - J. High Energy Phys , 2000
"... Three of the four viable solutions of the solar neutrino problem are consistent with close to maximal leptonic mixing: sin 2 θ12 = 1 2 (1 − ǫ) with |ǫ | ≪ 1. Theoretical models can naturally explain such a situation if approximate horizontal symmetries force a pseudo-Dirac structure on the neutrino ..."
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Three of the four viable solutions of the solar neutrino problem are consistent with close to maximal leptonic mixing: sin 2 θ12 = 1 2 (1 − ǫ) with |ǫ | ≪ 1. Theoretical models can naturally explain such a situation if approximate horizontal symmetries force a pseudo-Dirac structure

Bottom-up model for maximal νµ − ντ mixing

by Nicole F. Bell, Raymond R. Volkas , 2000
"... We construct a model which provides maximal mixing between a pseudo-Dirac νµ/ντ pair, based on a local U(1)Lµ−Lτ symmetry. Its strengths, weaknesses and phenomenological consequences are examined. The mass gap necessitated by the pseudo-Dirac structure is most naturally associated with the LSND anom ..."
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We construct a model which provides maximal mixing between a pseudo-Dirac νµ/ντ pair, based on a local U(1)Lµ−Lτ symmetry. Its strengths, weaknesses and phenomenological consequences are examined. The mass gap necessitated by the pseudo-Dirac structure is most naturally associated with the LSND

On noncommutative and pseudo-Riemannian geometry

by Alexander Strohmaier - J. Geom. Phys
"... We introduce the notion of a pseudo-Riemannian spectral triple which gen-eralizes the notion of spectral triple and allows for a treatment of pseudo-Riemannian manifolds within a noncommutative setting. It turns out that the relevant spaces in noncommutative pseudo-Riemannian geometry are not Hilber ..."
Abstract - Cited by 16 (0 self) - Add to MetaCart
are not Hilbert spaces any more but Krein spaces, and Dirac operators are Krein-selfadjoint. We show that the noncommutative tori can be endowed with a pseudo-Riemannian structure in this way. For the noncommutative tori as well as for pseudo-Riemannian spin manifolds the dimension, the signature of the metric

Spectral functionals, nonholonomic Dirac operators, and noncommutative Ricci flows

by Sergiu I. Vacaru
"... (Pseudo) Riemannian fundamental geometric structures [metrics, frames and linear connections] transform into generalized ones modelling nonholonomic spaces with generic local anisotropy and/or noncommutative and nonsymmetric variables, and inversely, under nonholonomic Ricci flows, when the evolutio ..."
Abstract - Cited by 19 (14 self) - Add to MetaCart
(Pseudo) Riemannian fundamental geometric structures [metrics, frames and linear connections] transform into generalized ones modelling nonholonomic spaces with generic local anisotropy and/or noncommutative and nonsymmetric variables, and inversely, under nonholonomic Ricci flows, when

Seiberg-Witten Equations on Pseudo-Riemannian Spin c Manifolds With Neutral Signature

by unknown authors
"... Pseudo-Riemannian spin c manifolds were introduced by Ikemakhen in [7]. In the present work we consider pseudo-Riemannian 4−manifolds with neutral signature whose structure groups are SO+(2, 2). We prove that such manifolds have pseudo-Riemannian spin c structure. We construct spinor bundle S and ha ..."
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Pseudo-Riemannian spin c manifolds were introduced by Ikemakhen in [7]. In the present work we consider pseudo-Riemannian 4−manifolds with neutral signature whose structure groups are SO+(2, 2). We prove that such manifolds have pseudo-Riemannian spin c structure. We construct spinor bundle

On the mistery of the missing pie in graphene

by Paola Giacconi, Roberto Soldati , 2009
"... We investigate in some detail the structure of the electromagnetic current density for the pseudo-relativistic massless spinor effective model for graphene. It is shown that the pseudo-relativistic massless Dirac field theory in 2+1 space-time dimensions and in the presence of a constant homogeneous ..."
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We investigate in some detail the structure of the electromagnetic current density for the pseudo-relativistic massless spinor effective model for graphene. It is shown that the pseudo-relativistic massless Dirac field theory in 2+1 space-time dimensions and in the presence of a constant

THE ELECTRO-WEAK AND COLOR BUNDLES FOR THE STANDARD MODEL IN A GRAVITATION FIELD.

by R. A. Sharipov , 2006
"... Abstract. It is known that the Standard Model describing all of the currently known elementary particles is based on the U(1)×SU(2)×SU(3) symmetry. In order to implement this symmetry on the ground of a non-flat space-time manifold one should introduce three special bundles. Some aspects of the math ..."
Abstract - Cited by 4 (3 self) - Add to MetaCart
: (1) a pseudo-Euclidean Minkowski-type metric g; (2) an orientation; (3) a polarization (see details in [4]). The Dirac bundle DM is linked to the above three structures through frame pairs. The most popular frame pairs are listed in the following table: Canonically orthonormal chiral frames

A Note on Clifford Algebras in Gravitational Physics. Thomas Rot

by unknown authors , 2009
"... u ß v Clifford algebras are widely used in quantum mechanics. The gamma matrices, found in the Dirac equation, are a representation of the four dimensional Clifford algebra with Lorentzian signature. In other areas of physics the Clifford structure is not used often. We investigate the use of these ..."
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of these algebras in gravitational physics. A review of Clifford algebras are given and the algebraic structure is lifted to the tangent bundle for any (pseudo)-Riemannian manifold. We discover that certain sections of the Clifford bundle can be interpreted as Lorentz transformations. The Dirac operator is defined
Results 1 - 10 of 40