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Related papers: Spectral flow for nonunital spectral triples

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The Vafa-Witten equations (with or without a mass term) constitute a non-linear, first order system of differential equations on a given oriented, compact, Riemannian 4-manifold. Because these are the variational equations of a functional,…

Differential Geometry · Mathematics 2024-07-12 Clifford Henry Taubes

We show that continuous group homomorphisms between unitary groups of unital C*-algebras induce maps between spaces of continuous real-valued affine functions on the trace simplices. Under certain $K$-theoretic regularity conditions, these…

Operator Algebras · Mathematics 2023-11-22 Pawel Sarkowicz

We define the notion of von Neumann spectral triple and consider the associated index problem. We compute the analytic Chern-Connes character of such a von Neumann spectral triple and prove the corresponding local formula for its Hochschild…

K-Theory and Homology · Mathematics 2011-04-26 M-T. Benameur , T. Fack

The author's recent results on spectral invariant dense subalgebras of C*-algebras associated with dynamical systems are summarized. If G is a compactly generated polynomial growth Type R Lie group, and the action of G on S(M) (Schwartz…

funct-an · Mathematics 2016-02-15 Larry B. Schweitzer

The notion of good spectral triple is initiated. We prove firstly that any regular spectral triple may be embedded in a good spectral triple, so that, in non-commutative geometry, we can restricts to deal only with good spectral triples.…

Mathematical Physics · Physics 2007-05-23 J. Marion , K. Valavane

We consider smooth flows preserving a smooth invariant measure, or, equivalently, locally Hamiltonian flows on compact orientable surfaces and show that almost every such locally Hamiltonian flow with only simple saddles has singular…

Dynamical Systems · Mathematics 2025-05-20 Krzysztof Frączek , Adam Kanigowski , Corinna Ulcigrai

In this paper, we continue to study the fractional harmonic gradient flow on $S^{n-1}$ taking values in a general closed manifold $N \subset \mathbb{R}^n$, addressing global existence and uniqueness of solutions of energy class with…

Analysis of PDEs · Mathematics 2021-09-24 Jerome Wettstein

We propose a construction for spectral triple on algebras associated with subshifts. One-dimensional subshifts provide concrete examples Z-actions on Cantor sets. The C*-algebra of this dynamical system is generated by functions in C(X) and…

Operator Algebras · Mathematics 2015-11-18 Antoine Julien , Ian F. Putnam

In an attempt to propose more general conditions for decoherence to occur, we study spectral and ergodic properties of unital, completely positive maps on not necessarily unital $C^*$-algebras, with a particular focus on gapped maps for…

Operator Algebras · Mathematics 2021-10-14 Francesco Fidaleo , Federico Ottomano , Stefano Rossi

In 2005 a new topological invariant defined in terms of the Brouwer degree of a determinant map, was introduced by Musso, Pejsachowicz and the first name author for counting the conjugate points along a semi-Riemannian geodesic. This…

Classical Analysis and ODEs · Mathematics 2020-06-02 Alessandro Portaluri , Li Wu

This paper describes a topological method to compute the spectral flow of a family of twisted Dirac operators, it includes two detailed examples. Briefly, a formula of Atiyah, Patodi and Singer expresses the spectral flow in terms of…

Geometric Topology · Mathematics 2007-05-23 Dave Auckly

The Effros-Shen algebra corresponding to an irrational number $\theta$ can be described by an inductive sequence of direct sums of matrix algebras, where the continued fraction expansion of $\theta$ encodes the dimensions of the summands,…

Operator Algebras · Mathematics 2025-10-22 Konrad Aguilar , Samantha Brooker , Jack Spielberg

We construct a spectral triple for the C$^*$-algebra of continuous functions on the space of $p$-adic integers by using a rooted tree obtained from coarse-grained approximation of the space, and the forward derivative on the tree.…

Operator Algebras · Mathematics 2015-06-19 Slawomir Klimek , Matt McBride , Sumedha Rathnayake

The definition of the spectral action involves the trace operator over states in the physical Hilbert space. We show that in the presence of chiral fermions there are consistency conditions on the fermionic representations. These conditions…

High Energy Physics - Theory · Physics 2007-05-23 Ali H. Chamseddine

It is shown that any bundle of KMS state spaces which can occur for a flow on a unital separable C*-algebra with a trace state can also be realized by a flow on any given unital infinite-dimensional simple AF algebra with a tracial state…

Operator Algebras · Mathematics 2021-10-13 George A. Elliott , Klaus Thomsen

We consider the relationship between derivations $d$ and $g$ of a Banach algebra $B$ that satisfy $\s(g(x)) \subseteq \s(d(x))$ for every $x\in B$, where $\s(\, . \,)$ stands for the spectrum. It turns out that in some basic situations, say…

Operator Algebras · Mathematics 2012-04-24 M. Brešar , B. Magajna , Š. Špenko

Continuing our study of spectral triples on quantum domains, we look at unbounded invariant and covariant derivations in the quantum annulus. In particular, we investigate whether such derivations can be implemented by operators with…

Operator Algebras · Mathematics 2018-03-06 Slawomir Klimek , Matt McBride , Sumedha Rathnayake

We give a functional analytical proof of the equality between the Maslov index of a semi-Riemannian geodesic and the spectral flow of the path of self-adjoint Fredholm operators obtained from the index form. This fact, together with recent…

Differential Geometry · Mathematics 2007-05-23 Paolo Piccione , Alessandro Portaluri , Daniel V. Tausk

For tri-diagonal matrices arising in the simplified Jaynes--Cummings model, we give an asymptotics of the eigenvalues, prove a trace formula and show that the Spectral Riemann Surface is irreducible.

Mathematical Physics · Physics 2007-05-23 Plamen Djakov , Boris Mityagin

This article investigates spectral redundancy, a concept initially introduced by Alberto Seeger. Spectral redundancy arises when different connected induced subgraphs of a graph share the same spectral radius in their adjacency spectrum.…

Combinatorics · Mathematics 2025-07-17 Pawan Kumar , S. Pirzada , S. Merajuddin
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