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Related papers: Dirac operators on quasi-Hamiltonian G-spaces

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The paper considers the Dirac operator on a Riemann surface coupled to a symplectic holomorphic vector bundle W. Each spinor in the null-space generates through the moment map a Higgs bundle, and varying W one obtains a holomorphic…

Algebraic Geometry · Mathematics 2017-07-12 Nigel Hitchin

We construct conjugate-linear perturbations of twisted spinc Dirac operators on compact almost hermitian manifolds of dimension congruent to 2 or 6 modulo 8, employing the conjugate-linear Hodge star operator rescaled by unit complex…

Differential Geometry · Mathematics 2025-08-19 Junho Lee

Let $(\overline M,\overline g)$ be a time- and space-oriented Lorentzian spin manifold, and let $M$ be a compact spacelike hypersurface of $\overline M$ with induced Riemannian metric $g$ and second fundamental form $K$. If $(\overline…

Differential Geometry · Mathematics 2021-03-23 Bernd Ammann , Jonathan Glöckle

By a result of Nagy, the C*-algebra of continuous functions on the q-deformation G_q of a simply connected semisimple compact Lie group G is KK-equivalent to C(G). We show that under this equivalence the K-homology class of the Dirac…

Operator Algebras · Mathematics 2011-02-02 Sergey Neshveyev , Lars Tuset

We construct in projective differential geometry of the real dimension $2$ higher symmetry algebra of the symplectic Dirac operator ${D}\kern-0.5em\raise0.22ex\hbox{/}_s$ acting on symplectic spinors. The higher symmetry differential…

Differential Geometry · Mathematics 2018-03-20 Petr Somberg , Josef Šilhan

The semiclassical limit for Dirac particles interacting with a static gravitational field is investigated. A Foldy-Wouthuysen transformation which diagonalizes at the semiclassical order the Dirac equation for an arbitrary static spacetime…

High Energy Physics - Theory · Physics 2008-11-26 Pierre Gosselin , Alain Bérard , Herve Mohrbach

Starting with a new theory of symmetries generated by isometries in field theories with spin, one finds the generators of the spinor representation in backgrounds with a given symmetry. In this manner one obtains a collection of conserved…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ion I Cotăescu

We develop two connections between the quantitative framework of operator $K$-theory for geometric $C^*$-algebras and the problem of positive scalar curvature. First, we introduce a quantitative notion of higher index and use it to give a…

K-Theory and Homology · Mathematics 2024-09-02 Hao Guo , Zhizhang Xie , Guoliang Yu

We define the quasi-compact Higgs $G^{\mathbb C}$-bundles over singular curves introduced in our previous paper for the Lie group SL($N$). The quasi-compact structure means that the automorphism groups of the bundles are reduced to the…

Mathematical Physics · Physics 2018-10-26 S. Kharchev , A. Levin , M. Olshanetsky , A. Zotov

We develop by example a type of index theory for non-Fredholm operators. A general framework using cyclic homology for this notion of index was introduced in a separate article [CaKa13] where it may be seen to generalise earlier ideas of…

Functional Analysis · Mathematics 2014-05-20 Alan Carey , Harald Grosse , Jens Kaad

We study the Dirac spectrum on compact Riemannian spin manifolds $M$ equipped with a metric connection $\nabla$ with skew torsion $T\in\Lambda^3 M$ in the situation where the tangent bundle splits under the holonomy of $\nabla$ and the…

Differential Geometry · Mathematics 2013-11-06 Ilka Agricola , Hwajeong Kim

The Dirac equation in a curved spacetime depends on a field of coefficients (essentially the Dirac matrices), for which a continuum of different choices are possible. We study the conditions under which a change of the coefficient fields…

General Relativity and Quantum Cosmology · Physics 2011-07-14 Mayeul Arminjon , Frank Reifler

In frame of Dirac quantum field theory that describes electrons and positrons as elementary excitations of the spinor field, the generalized operator of the spin-orbit interaction is obtained using non-relativistic approximation in the…

Mesoscale and Nanoscale Physics · Physics 2020-04-01 A. A. Eremko , L. Brizhik , V. M. Loktev

We construct a 2+1 dimensional classical gauge theory on manifolds with spin structure whose action is a refinement of the Atiyah-Patodi- Singer eta-invariant for twisted Dirac operators. We investigate the properties of the Lagrangian…

Differential Geometry · Mathematics 2007-05-23 Jerome A. Jenquin

In this paper, we establish two kinds of Kastler-Kalau-Walze type theorems for Dirac operators and signature operators twisted by a vector bundle with a non-unitary connection on six-dimensional manifolds with boundary.

Differential Geometry · Mathematics 2019-07-23 Sining Wei , Yong Wang

Properties of the Cauchy-Riemann-Fueter equation for maps between quaternionic manifolds are studied. Spaces of solutions in case of maps from a K3-surface to the cotangent bundle of a complex projective space are computed. A relationship…

Differential Geometry · Mathematics 2008-05-30 Andriy Haydys

We study spectral triples over noncommutative principal U(1) bundles. Basing on the classical situation and the abstract algebraic approach, we propose an operatorial definition for a connection and compatibility between the connection and…

Mathematical Physics · Physics 2013-11-21 Ludwik Dabrowski , Andrzej Sitarz

This article gives a geometric interpretation of the spin base formulation with local spin base invariance of spinors on a curved space-time and in particular of a central element, the global Dirac structure, in terms of principal and…

High Energy Physics - Theory · Physics 2022-05-04 Claudio Emmrich

Let (M,g) be a compact Riemannian spin manifold. The Atiyah-Singer index theorem yields a lower bound for the dimension of the kernel of the Dirac operator. We prove that this bound can be attained by changing the Riemannian metric g on an…

Differential Geometry · Mathematics 2016-03-03 Bernd Ammann , Mattias Dahl , Emmanuel Humbert

We modify the construction of the spectral triple over an algebra of holonomy loops by introducing additional parameters in form of families of matrices. These matrices generalize the already constructed Euler-Dirac type operator over a…

High Energy Physics - Theory · Physics 2009-11-16 Johannes Aastrup , Jesper M. Grimstrup , Mario Paschke