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Related papers: Dirac structures and Dixmier-Douady bundles

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We study some aspects of the generalized geometry of nilmanifolds and examine to which extent different types of fluxes can coexist on them. Nilmanifolds constitute a class of homogeneous spaces which are interesting in string…

High Energy Physics - Theory · Physics 2014-04-10 Athanasios Chatzistavrakidis , Larisa Jonke , Olaf Lechtenfeld

In the first part of this paper, given a smooth family of Dirac-type operators on an odd-dimensional closed manifold, we construct an abelian gerbe-with-connection whose curvature is the three-form component of the Atiyah-Singer families…

Differential Geometry · Mathematics 2009-11-07 John Lott

We explore algebro-geometric properties of the moduli space of holomorphic Lie algebroid ($ \mathcal{L} $) connections on a compact Riemann surface $X$ of genus $g \,\geq\, 3$. A smooth compactification of the moduli space of…

Algebraic Geometry · Mathematics 2024-04-17 Indranil Biswas , Anoop Singh

A $\mathbb Z_2$-harmonic spinor on a 3-manifold $Y$ is a solution of the Dirac equation on a bundle that is twisted around a submanifold $\mathcal Z$ of codimension 2 called the singular set. This article investigates the local structure of…

Differential Geometry · Mathematics 2025-01-29 Gregory J. Parker

We present a universal Dirac operator for noncommutative spin and spin^c bundles over fuzzy complex projective spaces. We give an explicit construction of these bundles, which are described in terms of finite dimensional matrices, calculate…

High Energy Physics - Theory · Physics 2008-11-26 Brian P. Dolan , Idrish Huet , Sean Murray , Denjoe O'Connor

Extending ideas of twisted equivariant $K$-theory, we construct twisted versions of the representation rings for Lie superalgebras and Lie supergroups, built from projective $\Z_{2}$-graded representations with a given cocycle. We then…

Representation Theory · Mathematics 2007-05-23 Gregory D. Landweber

The Dirac operator for a manifold Q, and its chirality operator when Q is even dimensional, have a central role in noncommutative geometry. We systematically develop the theory of this operator when Q=G/H, where G and H are compact…

High Energy Physics - Theory · Physics 2009-11-07 A. P. Balachandran , Giorgio Immirzi , Joohan Lee , Peter Presnajder

We prove that the kernels of the restrictions of symplectic Dirac or symplectic Dirac-Dolbeault operators on natural subspaces of polynomial valued spinor fields are finite dimensional on a compact symplectic manifold. We compute those…

Symplectic Geometry · Mathematics 2015-06-16 Michel Cahen , Simone Gutt , Laurent La Fuente Gravy , John Rawnsley

We construct a Connes spectral triple or `Dirac operator' on the non-reduced fuzzy sphere $C_\lambda[S^2]$ as realised using quantum Riemannian geometry with a central quantum metric $g$ of Euclidean signature and its associated quantum…

Quantum Algebra · Mathematics 2022-02-09 Evelyn Lira-Torres , Shahn Majid

We introduce the notion of continuous twisted partial actions of a locally compact group on a C*-algebra. With such, we construct an associated C*-algebraic bundle called the semidirect product bundle. Our main theorem shows that, given any…

funct-an · Mathematics 2008-02-03 Ruy Exel

Let $M$ be an orientable compact flat Riemannian manifold endowed with a spin structure. In this paper we determine the spectrum of Dirac operators acting on smooth sections of twisted spinor bundles of $M$, and we derive a formula for the…

Differential Geometry · Mathematics 2007-05-23 Roberto Miatello , Ricardo Podesta

We find sufficient conditions for the absence of harmonic $L^2$ spinors on spin manifolds constructed as cone bundles over a compact K\"ahler base. These conditions are fulfilled for certain perturbations of the Euclidean metric, and also…

Differential Geometry · Mathematics 2019-01-08 Andrei Moroianu , Sergiu Moroianu

Let $(M,g)$ be a pseudo-Riemannian manifold of signature $(p,q)$. We compute the obstruction for a vector bundle $S$ over $(M,g)$ to admit a Dirac operator whose principal symbol induces on $S$ the structure of a bundle of irreducible real…

Differential Geometry · Mathematics 2022-02-03 C. I. Lazaroiu , C. S. Shahbazi

This paper develops the theory of discrete Dirac reduction of discrete Lagrange-Dirac systems with an abelian symmetry group acting on the configuration space. We begin with the linear theory and, then, we extend it to the nonlinear setting…

Mathematical Physics · Physics 2023-03-10 Álvaro Rodríguez Abella , Melvin Leok

We show that in the context of two-dimensional sigma models minimal coupling of an ordinary rigid symmetry Lie algebra $\mathfrak{g}$ leads naturally to the appearance of the "generalized tangent bundle" $\mathbb{T}M \equiv TM \oplus T^*M$…

High Energy Physics - Theory · Physics 2015-06-22 Alexei Kotov , Vladimir Salnikov , Thomas Strobl

Whatever it is that animates anima and breathes life into higher algebra, this something leaves its trace in the structure of a Dirac ring on the homotopy groups of a commutative algebra in spectra. In the prequel to this paper, we…

Algebraic Topology · Mathematics 2024-01-03 Lars Hesselholt , Piotr Pstragowski

In this paper, we solve the problem of giving a gauge-theoretic description of the natural Dirac structure on a Lie Group which plays a prominent role in the theory of D- branes for the Wess-Zumino-Witten model as well as the theory of…

Symplectic Geometry · Mathematics 2017-09-27 Alejandro Cabrera , Marco Gualtieri , Eckhard Meinrenken

The homotopy groups of a commutative algebra in spectra form a commutative algebra in the symmetric monoidal category of graded abelian groups. The grading and the Koszul sign rule are remnants of the structure encoded by anima as opposed…

Number Theory · Mathematics 2023-04-27 Lars Hesselholt , Piotr Pstragowski

It is known that the bundle of Dirac spinors is produced as a direct sum of two bundles - the bundle of chiral spinors and its Hermitian conjugate bundle. In this paper some aspects of metric connections for chiral and Dirac spinors are…

Differential Geometry · Mathematics 2007-05-23 Ruslan Sharipov

This paper exhibits equivalences of 2-stacks between certain models of $\mathbb{S}^1$-gerbes and differential 3-cocycles. We focus primarily on the model of Dixmier-Douady bundles, and provide an equivalence between the 2-stack of…

Differential Geometry · Mathematics 2018-09-05 Derek Krepski , Jordan Watts