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Related papers: Equivariant Lorentzian Spectral Triples

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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 construct a canonical geometrically realised Connes spectral triple or `Dirac operator' $D\!\!\!/$ from the data of a quantum metric $g\in \Omega^1\otimes_A\Omega^1$ and quantum Levi-Civita bimodule connection, at the pre-Hilbert space…

Quantum Algebra · Mathematics 2023-05-16 Shahn Majid

In this article we develop some elementary aspects of a theory of symmetry in sub-Lorentzian geometry. First of all we construct invariants characterizing isometric classes of sub-Lorentzian contact 3 manifolds. Next we characterize vector…

Differential Geometry · Mathematics 2015-04-20 Marek Grochowski , Ben Warhurst

We construct spectral triples in a sense of noncommutative differential geometry, associated with a Riemannian foliation on a compact manifold, and describe its dimension spectrum.

dg-ga · Mathematics 2008-02-03 Yuri A. Kordyukov

A proper etale Lie groupoid is modelled as a (noncommutative) spectral geometric space. The spectral triple is built on the algebra of smooth functions on the groupoid base which are invariant under the groupoid action. Stiefel-Whitney…

Mathematical Physics · Physics 2014-12-16 Antti J. Harju

The central notion in Connes' formulation of non commutative geometry is that of a spectral triple. Given a homogeneous space of a compact quantum group, restricting our attention to all spectral triples that are `well behaved' with respect…

Quantum Algebra · Mathematics 2014-06-05 Partha Sarathi Chakraborty , Arup Kumar Pal

We formulate the notion of equivariance of an operator with respect to a covariant representation of a C^*-dynamical system. We then use a combinatorial technique used by the authors earlier in characterizing spectral triples for SU_q(2) to…

Quantum Algebra · Mathematics 2007-05-23 Partha Sarathi Chakraborty , Arupkumar Pal

We consider Lie groups equipped with a left-invariant cyclic Lorentzian metric. As in the Riemannian case, in terms of homogeneous structures, such metrics can be considered as different as possible from bi-invariant metrics. We show that…

Differential Geometry · Mathematics 2015-04-30 M. Castrillon Lopez , G. Calvaruso

Let G be a finitely generated discrete group. The standard spectral triple on the group C*-algebra C*(G) is shown to admit the quantum group of orientation preserving isometries. This leads to new examples of compact quantum groups. In…

Operator Algebras · Mathematics 2015-05-18 Jyotishman Bhowmick , Adam Skalski

Equivariance under the action of Uq(so(5)) is used to compute the left regular and (chiral) spinorial representations of the algebra of the orthogonal quantum 4-sphere S^4_q. These representations are the constituents of a spectral triple…

Quantum Algebra · Mathematics 2008-02-28 Francesco D'Andrea , Ludwik Dabrowski , Giovanni Landi

In this paper, we give a geometric expression for the multiplicities of the equivariant index of a spin-c Dirac operator.

Differential Geometry · Mathematics 2015-12-23 Paul-Emile Paradan , Michele Vergne

We review recent progress in the analytic study of random matrix models suggested by noncommutative geometry. One considers fuzzy spectral triples where the space of possible Dirac operators is assigned a probability distribution. These…

High Energy Physics - Theory · Physics 2022-10-12 Hamed Hessam , Masoud Khalkhali , Nathan Pagliaroli , Luuk Verhoeven

We introduce a new class of natural, explicitly defined, transversally elliptic differential operators over manifolds with compact group actions. Under certain assumptions, the symbols of these operators generate all the possible values of…

Differential Geometry · Mathematics 2021-01-28 Igor Prokhorenkov , Ken Richardson

We study equivariant birationality from the perspective of derived categories. We produce examples of nonlinearizable but stably linearizable actions of finite groups on smooth cubic fourfolds.

Algebraic Geometry · Mathematics 2023-04-19 Christian Böhning , Hans-Christian Graf von Bothmer , Yuri Tschinkel

We review the motivation, construction and physical interpretation of a semi-finite spectral triple obtained through a rearrangement of central elements of loop quantum gravity. The triple is based on a countable set of oriented graphs and…

High Energy Physics - Theory · Physics 2009-08-05 Johannes Aastrup , Jesper M. Grimstrup , Ryszard Nest

We solve for quantum-geometrically realised spectral triples or `Dirac operators' on the noncommutative torus $\Bbb C_\theta[T^2]$ and on the algebra $M_2(\Bbb C)$ of $2\times 2$ matrices with their standard quantum metrics and associated…

Quantum Algebra · Mathematics 2023-06-21 E. Lira-Torres , S. Majid

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

We give a geometrical construction of Connes spectral triples or noncommutative Dirac operators $D$ starting with a bimodule connection on the proposed spinor bundle. The theory is applied to the example of $M_2(\Bbb C)$, and also applies…

Quantum Algebra · Mathematics 2015-09-04 Edwin Beggs , Shahn Majid

We investigate examples of quasi-spectral triples over two-dimensional commutative sphere, which are obtained by modifying the order-one condition. We find equivariant quasi-Dirac operators and prove that they are in a topologically…

Mathematical Physics · Physics 2018-06-04 Andrzej Sitarz

We study sub-Dirac operators that are associated with left-invariant bracket-generating sub-Riemannian structures on compact quotients of nilpotent semi-direct products $G=\mathbb{R}^n\rtimes_A\mathbb{R}$. We will prove that these operators…

Spectral Theory · Mathematics 2013-11-12 Ines Kath , Oliver Ungermann