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Related papers: Spectral flow for nonunital spectral triples

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We use the notion of generalized signatures at a singularity of a smooth curve of symmetric bilinear forms to determine a formula for the computation of the Maslov index in the case of a real-analytic path having possibly non transversal…

Differential Geometry · Mathematics 2007-05-23 R. Giambo , P. Piccione , A. Portaluri

In this article, we give a general construction of spectral triples from certain Lie group actions on unital C*-algebras. If the group G is compact and the action is ergodic, we actually obtain a real and finitely summable spectral triple…

Operator Algebras · Mathematics 2013-02-05 Olivier Gabriel , Martin Grensing

In the setting of a proper, cocompact action by a locally compact, unimodular group $G$ on a Riemannian manifold, we construct equivariant spectral flow of paths of Dirac-type operators. This takes values in the $K$-theory of the group…

Operator Algebras · Mathematics 2025-02-04 Peter Hochs , Aquerman Yanes

We introduce the notion of the joint spectral flow, which is a generalization of the spectral flow, by using Segal's model of the connective $K$-theory spectrum. We apply it for some localization results of indices motivated by Witten's…

K-Theory and Homology · Mathematics 2016-01-20 Yosuke Kubota

We show that the SU(3) Casson invariant for spliced sums along certain torus knots equals 16 times the product of their SU(2) Casson knot invariants. The key step is a splitting formula for su(n) spectral flow for closed 3-manifolds split…

Geometric Topology · Mathematics 2014-11-11 Hans U. Boden , Benjamin Himpel

This work explores the spectra of quantum graphs where the Schr\"odinger operator on the edges is equipped with a potential. The scattering approach, which was originally introduced for the potential free case, is extended to this case and…

Mathematical Physics · Physics 2015-06-11 Ralf Rueckriemen , Uzy Smilansky

It has been shown recently that spectral flow admits a natural integer-valued extension to essential spectrum. This extension admits four different interpretations; two of them are singular spectral shift function and total resonance index.…

Spectral Theory · Mathematics 2016-07-29 Nurulla Azamov

In \cite{APSIII} Atiyah, Patodi and Singer introduced spectral flow for elliptic operators on odd dimensional compact manifolds. They argued that it could be computed from the Fredholm index of an elliptic operator on a manifold of one…

Functional Analysis · Mathematics 2022-06-22 Alan Carey , Galina Levitina , Denis Potapov , Fedor Sukochev

This paper is comprised of two related parts. First we discuss which k-graph algebras have faithful gauge invariant traces, where the gauge action of $\T^k$ is the canonical one. We give a sufficient condition for the existence of such a…

Operator Algebras · Mathematics 2007-05-23 David Pask , Adam Rennie , Aidan Sims

We give an elementary proof of a celebrated theorem of Cappell, Lee and Miller which relates the Maslov index of a pair of paths of Lagrangian subspaces to the spectral flow of an associated path of selfadjoint first-order operators. We…

Dynamical Systems · Mathematics 2019-04-19 Marek Izydorek , Joanna Janczewska , Nils Waterstraat

We prove that unital surjective spectral isometries on certain non-simple unital C*-algebras are Jordan isomorphisms. Along the way, we establish several general facts in the setting of semisimple Banach algebras.

Functional Analysis · Mathematics 2011-11-01 Martin Mathieu , Ahmed R. Sourour

We prove an abstract compactness result for gradient flow lines of a non-local unregularized gradient flow equation on a scale Hilbert space. This is the first step towards Floer theory on scale Hilbert spaces.

Functional Analysis · Mathematics 2022-12-29 Peter Albers , Urs Frauenfelder , Felix Schlenk

We develop spectral theorems for nonautonomous linear difference systems, considering different types of $\mu$-dichotomies, both uniform and nonuniform. In the nonuniform case, intriguing scenarios emerge -- that have been employed but…

Dynamical Systems · Mathematics 2025-01-09 Álvaro Castañeda , Claudio A. Gallegos , Néstor Jara

A characterization is given for directed graphs that yield graph $C^*$-algebras with continuous trace. This is established for row-finite graphs with no sources first using a groupoid approach, and extended to the general case via the…

Operator Algebras · Mathematics 2015-12-15 Danny Crytser

We formulate a noncommutative generalization of the Ricci flow theory in the framework of spectral action approach to noncommutative geometry. Grisha Perelman's functionals are generated as commutative versions of certain spectral…

Mathematical Physics · Physics 2011-06-02 Sergiu I. Vacaru

Associative spectra of graph algebras are examined with the help of homomorphisms of DFS trees. Undirected graphs are classified according to the associative spectra of their graph algebras; there are only three distinct possibilities:…

Combinatorics · Mathematics 2021-05-20 Erkko Lehtonen , Tamás Waldhauser

We define a notion of equivariant non-degeneracy of $G$-maps to introduce the class of equivariantly non-degenerate flows on smooth compact manifolds with compact Lie group action. We prove genericity of this class and use this result to…

Dynamical Systems · Mathematics 2013-01-31 Philipp Wruck

We construct a spectral-triple framework for a noncommutative planar system associated with a fixed nondegenerate irreducible unitary sector of the kinematical symmetry group $G_{\mathrm{NC}}$, labelled by central parameters…

Mathematical Physics · Physics 2026-05-12 Md. Rafsanjany Jim , Tanmoy Kumar Sarkar , S. Hasibul Hassan Chowdhury

We consider a continuous curve of linear elliptic formally self-adjoint differential operators of first order with smooth coefficients over a compact Riemannian manifold with boundary together with a continuous curve of global elliptic…

Differential Geometry · Mathematics 2014-06-04 Bernhelm Booss-Bavnbek , Chaofeng Zhu

It is recently shown by Asahara-Funakawa-Seki-Tanaka that existing index theory for chirally symmetric (discrete-time) quantum walks can be extended to the setting of non-unitary quantum walks. More precisely, they consider a certain…

Mathematical Physics · Physics 2022-05-24 Chusei Kiumi , Kei Saito , Yohei Tanaka