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Related papers: Untwisting twisted spectral triples

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We study two ways of summing an infinite family of noncommutative spectral triples. First, we propose a definition of the integration of spectral triples and give an example using algebras of Toeplitz operators acting on weighted Bergman…

Mathematical Physics · Physics 2016-11-18 Kevin Falk

We classify the twists of almost commutative spectral triples that keep the Hilbert space and the Dirac operator untouched. The involved twisting operator is shown to be the product of the grading of a manifold by a finite dimensional…

Mathematical Physics · Physics 2021-12-14 Manuele Filaci , Pierre Martinetti

We systematically investigate ways to twist a real spectral triple via an algebra automorphism and in particular, we naturally define a twisted partner for any real graded spectral triple. Among other things we investigate consequences of…

Mathematical Physics · Physics 2016-09-21 Giovanni Landi , Pierre Martinetti

We construct a canonical noncommutative spectral triple for every oriented closed Riemannian manifold, which represents the fundamental class in the twisted K-homology of the manifold. This so-called "projective spectral triple" is Morita…

Differential Geometry · Mathematics 2014-07-01 Dapeng Zhang

Sharp Strichartz estimates are proved for Schr\"odinger and wave equations with Lipschitz coefficients satisfying additional structural assumptions. We use Phillips functional calculus as a substitute for Fourier inversion, which shows how…

Analysis of PDEs · Mathematics 2023-05-16 Dorothee Frey , Robert Schippa

We prove a local index formula in conformal geometry by computing the Connes-Chern character for the conformal Dirac (twisted) spectral triple recently constructed by Connes-Moscovici. Following an observation of Moscovici, the computation…

Operator Algebras · Mathematics 2014-11-17 Raphael Ponge , Hang Wang

Using Cayley graphs and Clifford algebras, we are able to give, for every finitely generated groups, a uniform construction of spectral triples with a generically non-trivial phase for the Dirac operator. Unfortunatly $D_{+}$ is index $0$,…

Operator Algebras · Mathematics 2016-11-10 Sebastien Palcoux

Using a Cayley complex (generalizing the Cayley graph) and Clifford algebras, we are able to give, for a large class of finitely presented groups, a uniform construction of spectral triples with $D_{+}$ of index 1.

Operator Algebras · Mathematics 2016-11-10 Sebastien Palcoux

We study twisted derived equivalences for schemes in the setting of spectral algebraic geometry. To this end, we introduce the notion of a twisted equivalence and show that a twisted equivalence for perfect spectral algebraic stacks…

Algebraic Geometry · Mathematics 2021-09-08 Chang-Yeon Chough

We prove new lossless Strichartz and spectral projection estimates on asymptotically hyperbolic surfaces, and, in particular, on all convex cocompact hyperbolic surfaces. In order to do this, we also obtain log-scale lossless Strichartz and…

Analysis of PDEs · Mathematics 2026-02-09 Xiaoqi Huang , Christopher D. Sogge , Zhongkai Tao , Zhexing Zhang

This article demonstrates how the transition from a (Riemannian) twisted spectral triple to a pseudo-Riemannian spectral triple arises within an almost-commutative spectral triple. This opens a new perspective on the Lorentzian signature…

Mathematical Physics · Physics 2025-05-07 Gaston Nieuviarts

We analyse the spectral edge regularity of a large class of magnetic Hamiltonians when the perturbation is generated by a globally bounded magnetic field. We can prove Lipschitz regularity of spectral edges if the magnetic field…

Spectral Theory · Mathematics 2015-07-23 Horia D. Cornean , Radu Purice

We classify and construct all real spectral triples over noncommutative Bieberbach manifolds, which are restrictions of irreducible real equivariant spectral triple over the noncommutative three-torus. We show that in the classical case the…

Quantum Algebra · Mathematics 2019-03-08 Piotr Olczykowski , Andrzej Sitarz

We consider the algebra $A$ of bounded operators on $L^2(\mathbb{R}^n)$ generated by quantizations of isometric affine canonical transformations. The algebra $A$ includes as subalgebras all noncommutative tori and toric orbifolds. We define…

Operator Algebras · Mathematics 2022-08-04 Anton Savin , Elmar Schrohe

Any oriented Riemannian manifold with a Spin-structure defines a spectral triple, so the spectral triple can be regarded as a noncommutative Spin-manifold. Otherwise for any unoriented Riemannian manifold there is the two-fold covering by…

Operator Algebras · Mathematics 2017-12-12 Petr Ivankov

A Dirac operator is presented that will yield a 1+ summable regular even spectral triple for all noncommutative compact surfaces defined as subalgebras of the Toeplitz algebra. Connes' conditions for noncommutative spin geometries are…

Operator Algebras · Mathematics 2020-02-26 Fredy Díaz García , Elmar Wagner

We propose a definition of a modular spectral triple which covers existing examples arising from KMS-states, Podles sphere and quantum SU(2). The definition also incorporates the notion of twisted commutators appearing in recent work of…

Operator Algebras · Mathematics 2011-11-29 Jens Kaad

We introduce a notion of an algebra of generalized pseudo-differential operators and prove that a spectral triple is regular if and only if it admits an algebra of generalized pseudo-differential operators. We also provide a self-contained…

Operator Algebras · Mathematics 2011-11-11 Otgonbayar Uuye

In the noncommutative geometry approach to the standard model we discuss the possibility to derive the extra scalar field sv- initially suggested by particle physicist to stabilize the electroweak vacuum - from a "grand algebra" that…

High Energy Physics - Theory · Physics 2015-09-02 Agostino Devastato

We extend to twisted spectral triples the fluctuations of the metric, as well as their gauge transformations. The former are bounded perturbations of the Dirac operator that arise when a spectral triple is exported between Morita equivalent…

Mathematical Physics · Physics 2018-05-23 Giovanni Landi , Pierre Martinetti