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Related papers: Dirac cohomology and character lifting

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This study is devoted to the profound implications of tilted Dirac cones on the quantum transport properties of two-dimensional (2D) Dirac materials. These materials, characterized by their linear conic energy dispersions in the vicinity of…

Mesoscale and Nanoscale Physics · Physics 2024-10-30 Rasha Al-Marzoog , Ali Rezaei , Zahra Noorinejad , Mohsen Amini , Ebrahim Ghanbari-Adivi , S. A. Jafari

We establish the factorization of the Dirac operator on an almost-regular fibration of spin$^c$ manifolds in unbounded KK-theory. As a first intermediate result we establish that any vertically elliptic and symmetric first-order…

Functional Analysis · Mathematics 2017-10-10 Jens Kaad , Walter D. van Suijlekom

We give a proof of the index theorem of lattice Wilson--Dirac operators, which states that the index of a twisted Dirac operator on the standard torus is described in terms of the corresponding lattice Wilson--Dirac operator. Our proof is…

Mathematical Physics · Physics 2020-09-09 Yosuke Kubota

Let X be a compact manifold with boundary, and suppose that the boundary is the total space of a fibration with base Y and fibre Z. Let D be a generalized Dirac operator associated to a Phi-metric g on X. Under the assumption that D is…

Differential Geometry · Mathematics 2007-05-23 Eric Leichtnam , Rafe Mazzeo , Paolo Piazza

A closed spin K\"ahler manifold of positive scalar curvature with smallest possible first eigenvalue of the Dirac operator is characterized by holomorphic spinors. It is shown that on any spin K\"ahler-Einstein manifold each holomorphic…

Differential Geometry · Mathematics 2007-05-23 Klaus-Dieter Kirchberg

It has been shown by Nistor that given any extension of associative algebras over C, the connecting morphism in periodic cyclic homology is compatible, under the Chern-Connes character, with the index morphism in lower algebraic K-theory.…

K-Theory and Homology · Mathematics 2009-11-01 Denis Perrot

Kasparov defined a distinguished K-homology fundamental class, so called the Dirac element. We prove a localization formula for the Dirac element in K-homology of crossed product of C^{*}-algebras. Then we define the quantization of…

Symplectic Geometry · Mathematics 2014-10-10 Yanli Song

We provide a purely local computation of the (elliptic) twisted (by "transpose-inverse") character of the representation \pi=I(\1) of PGL(3) over a p-adic field induced from the trivial representation of the maximal parabolic subgroup. This…

Representation Theory · Mathematics 2007-11-29 Yuval Z. Flicker , Dmitrii Zinoviev

This paper is the second part of a series of papers on noncommutative geometry and conformal geometry. In this paper, we compute explicitly the Connes-Chern character of an equivariant Dirac spectral triple. The formula that we obtain for…

Differential Geometry · Mathematics 2017-03-17 Raphael Ponge , Hang Wang

We consider the optical and transport properties in a model two-dimensional Hamiltonian which describes the merging of two Dirac points. At low energy, in the presence of an energy gap parameter $\Delta$, there are two distinct Dirac points…

Mesoscale and Nanoscale Physics · Physics 2019-08-09 J. P. Carbotte , E. J. Nicol

We reproduce the quantum cohomology of toric varieties (and of some hypersurfaces in projective spaces) as the cohomology of certain vertex algebras with differential. The deformation technique allows us to compute the cohomology of the…

Algebraic Geometry · Mathematics 2007-05-23 F. Malikov , V. Schechtman

Fermionic-type character formulae are presented for charged irreduciblemodules of the graded parafermionic conformal field theory associated to the coset $osp(1,2)_k/u(1)$. This is obtained by counting the weakly ordered `partitions'…

High Energy Physics - Theory · Physics 2009-11-10 L. Bégin , J. -F. Fortin , P. Jacob , P. Mathieu

A semiclassical theory of spin dynamics and transport is formulated using the Dirac electron model. This is done by constructing a wavepacket from the positive-energy electron band, and studying its structure and center of mass motion. The…

Mesoscale and Nanoscale Physics · Physics 2013-12-10 Chih-Piao Chuu , Ming-Che Chang , Qian Niu

In this paper we construct an explicit quasi-isomorphism to study the cyclic cohomology of a deformation quantization over a riemannian \'etale groupoid. Such a quasi-isomorphism allows us to propose a general algebraic index problem for…

Quantum Algebra · Mathematics 2015-05-13 M. J. Pflaum , H. Posthuma , X. Tang

The groups of differential characters of Cheeger and Simons admit a natural multiplicative structure. The map given by the squares of degree 2k differential characters reduces to a homomorphism of ordinary cohomology groups. We prove that…

Algebraic Topology · Mathematics 2007-05-23 Kiyonori Gomi

The issue of general covariance of spinors and related objects is reconsidered. Given an oriented manifold $M$, to each spin structure $\sigma$ and Riemannian metric $g$ there is associated a space $S_{\sigma, g}$ of spinor fields on $M$…

Mathematical Physics · Physics 2012-12-06 Ludwik Dabrowski , Giacomo Dossena

We revisit a construction principle of Fredholm operators using Hilbert complexes of densely defined, closed linear operators and apply this to particular choices of differential operators. The resulting index is then computed with the help…

Functional Analysis · Mathematics 2020-06-19 Dirk Pauly , Marcus Waurick

In a Minkowski spacetime, one may transform the Dirac wave function under the spin group, as one transforms coordinates under the Poincar\'e group. This is not an option in a curved spacetime. Therefore, in the equation proposed…

General Relativity and Quantum Cosmology · Physics 2012-04-30 Mayeul Arminjon , Frank Reifler

In this article, we obtain the exact solutions for bound states of tilted anisotropic Dirac materials under the action of external electric and magnetic fields with translational symmetry. In order to solve the eigenvalue equation that…

Mesoscale and Nanoscale Physics · Physics 2024-03-25 Julio A. Mojica-Zárate , Daniel O-Campa , Erik Díaz-Bautista

Various algebraic properties of Heilbronn's exponential sum can be deduced through the use of supercharacter theory, a novel extension of classical character theory due to Diaconis-Isaacs and Andre. This perspective yields a variety of…

Number Theory · Mathematics 2017-11-15 Stephan Ramon Garcia , Bob Lutz
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