English
Related papers

Related papers: Solvmanifolds and noncommutative tori with real mu…

200 papers

A Dirac operator D on quantized irreducible generalized flag manifolds is defined. This yields a Hilbert space realization of the covariant first-order differential calculi constructed by I. Heckenberger and S. Kolb. All differentials…

Quantum Algebra · Mathematics 2007-05-23 Ulrich Kraehmer

Jacobi operators appear as kinetic operators of several classes of noncommutative field theories (NCFT) considered recently. This paper deals with the case of bounded Jacobi operators. A set of tools mainly issued from operator and spectral…

Mathematical Physics · Physics 2015-08-07 Antoine Géré , Jean-Christophe Wallet

Looking for the universal covering of the smooth non-commutative torus leads to a curve of associative multiplications on the space $\Cal O_M'(\Bbb R^{2n})\cong \Cal O_C(\Bbb R^{2n})$ of Laurent Schwartz which is smooth in the deformation…

Quantum Algebra · Mathematics 2007-05-23 Michel Dubois-Violette , Andreas Kriegl , Yoshiaki Maeda , Peter W. Michor

For any compact orientable irreducible 3-manifold $N$ with empty or incompressible toral boundary, the twisted $L^2$-torsion is a non-negative function defined on the representation variety…

Geometric Topology · Mathematics 2025-02-18 Jianru Duan

We prove inverse spectral results for differential operators on manifolds and orbifolds invariant under a torus action. These inverse spectral results involve the asymptotic equivariant spectrum, which is the spectrum itself together with…

Spectral Theory · Mathematics 2014-02-03 Emily B. Dryden , Victor Guillemin , Rosa Sena-Dias

In [10], Dabrowski etc. gave spectral Einstein bilinear functionals of differential forms for the Hodge-Dirac operator $d+\delta$ on an oriented even-dimensional Riemannian manifold. In this paper, we generalize the results of Dabrowski…

Differential Geometry · Mathematics 2023-09-15 Tong Wu , Yong Wang

Consider the class of n-dimensional Riemannian spin manifolds with bounded sectional curvatures and diameter, and almost non-negative scalar curvature. Let r=1 if n=2,3 and r=2^{[n/2]-1}+1 if n\geq 4. We show that if the square of the Dirac…

Differential Geometry · Mathematics 2008-02-25 Bernd Ammann , Chad Sprouse

The Rarita-Schwinger operator is the twisted Dirac operator restricted to 3/2-spinors. Rarita-Schwinger fields are solutions of this operator which are in addition divergence-free. This is an overdetermined problem and solutions are rare;…

Differential Geometry · Mathematics 2021-05-24 Christian Baer , Rafe Mazzeo

For the q-deformation G_q, 0<q<1, of any simply connected simple compact Lie group G we construct an equivariant spectral triple which is an isospectral deformation of that defined by the Dirac operator D on G. Our quantum Dirac operator…

Operator Algebras · Mathematics 2007-05-23 Sergey Neshveyev , Lars Tuset

Assume that the compact Riemannian spin manifold $(M^n,g)$ admits a $G$-structure with characteristic connection $\nabla$ and parallel characteristic torsion ($\nabla T=0$), and consider the Dirac operator $D^{1/3}$ corresponding to the…

Differential Geometry · Mathematics 2013-11-06 Ilka Agricola , Thomas Friedrich , Mario Kassuba

In this article we describe extensions of some K-theory classes of Heisenberg modules over higher-dimensional noncommutative tori to projective modules over crossed products of noncommutative tori by finite cyclic groups, aka noncommutative…

Operator Algebras · Mathematics 2019-01-29 Sayan Chakraborty , Franz Luef

This paper proposes a new notion of smoothness of algebras, termed differential smoothness, that combines the existence of a top form in a differential calculus over an algebra together with a strong version of the Poincar\'e duality…

Quantum Algebra · Mathematics 2015-05-07 Tomasz Brzeziński , Andrzej Sitarz

The spectral eta function for certain families of Dirac operators on noncommutative $3$-torus is considered and the regularity at zero is proved. By using variational techniques, we show that $\eta_{D}(0)$ is a conformal invariant. By…

Quantum Algebra · Mathematics 2015-04-07 Ali Fathi , Masoud Khalkhali

The real Fourier-Mukai transform sends a section of a torus fibration to a connection over the total space of the dual torus fibration. By this method, Leung, Yau and Zaslow introduced deformed Hermitian Yang-Mills (dHYM) connections for…

Differential Geometry · Mathematics 2021-07-27 Kotaro Kawai , Hikaru Yamamoto

This paper mainly focuses on the CR analogue of the three-circle theorem in a complete noncompact pseudohermitian manifold of vanishing torsion being odd dimensional counterpart of K\"ahler geometry. In this paper, we show that the CR…

Differential Geometry · Mathematics 2018-01-31 Shu-Cheng Chang , Yingbo Han , Chien Lin

We derive a numerical approximation of the Laplace-Beltrami operator on compact surfaces embedded in $\mathbb{R}^3$ with an axial symmetry. To do so we use a noncommutative Laplace operator defined on the space of finite dimensional…

Numerical Analysis · Mathematics 2025-12-01 Damien Tageddine , Jean-Christophe Nave

Let $M$ be a compact boundaryless Riemannian manifold, carrying an effective and isometric action of a torus $T$, and $P_0$ an invariant elliptic classical pseudodifferential operator on $M$. In this note, we strengthen asymptotics for the…

Spectral Theory · Mathematics 2018-09-24 Pablo Ramacher

We prove the analogue of the Riemann-Roch formula for the noncommutative two torus $ A_{\theta} = C(\mathbb{T}_{\theta}^2)$ equipped with an arbitrary translation invariant complex structure and a Weyl factor represented by a positive…

Quantum Algebra · Mathematics 2015-06-16 Masoud Khalkhali , Ali Moatadelro

We demonstrate the possibility of topological states for non-Dirac electrons. Specifically it is shown that, because of the $C_{\rm 3}$ crystal symmetry and time reversal symmetry, $p_x$ and $p_y$ orbits accommodated on triangular lattice…

Mesoscale and Nanoscale Physics · Physics 2016-02-03 Qi-Feng Liang , Rui Yu , Jian Zhou , Xiao Hu

In this article, we study the asymptotic behavior of harmonic $2$-forms on $K3$ surfaces with Ricci-flat K\"ahler metrics, where metrics converge to the quotient of a flat $4$-torus by a finite group action. We can show that the space of…

Differential Geometry · Mathematics 2026-05-20 Kota Hattori