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We show that a recent spectral flow approach proposed by Berkolaiko-Cox-Marzuola for analyzing the nodal deficiency of the nodal partition associated to an eigenfunction can be extended to more general partitions. To be more precise, we…

Spectral Theory · Mathematics 2021-03-16 Bernard Helffer , Mikael Persson Sundqvist

We discuss some general properties of $\mathrm{TR}$ and its $K(1)$-localization. We prove that after $K(1)$-localization, $\mathrm{TR}$ of $H\mathbb{Z}$-algebras is a truncating invariant in the sense of Land--Tamme, and deduce $h$-descent…

K-Theory and Homology · Mathematics 2021-02-10 Akhil Mathew

First, we prove a local spectral flow formula (Theorem 3.7) for a differentiable curve of selfadjoint Fredholm operators. This formula enables us to prove in a simple way a general spectral flow formula. Secondly, we prove a splitting…

Differential Geometry · Mathematics 2007-05-23 Kenro Furutani , Nobukazu Otsuki

We discuss several natural metrics on spaces of unbounded self--adjoint operators and their relations, among them the Riesz and the graph metric. We show that the topologies of the spaces of Fredholm operators resp. invertible operators…

Functional Analysis · Mathematics 2007-05-23 Matthias Lesch

We generalise the local index formula of Connes and Moscovici to the case of spectral triples for a *-subalgebra \A of a general semifinite von Neumann algebra. In this setting it gives a formula for spectral flow along a path joining an…

Operator Algebras · Mathematics 2007-05-23 Alan L. Carey , John Phillips , Adam Rennie , Fyodor A. Sukochev

In this article we study generalised Dirac-Schr\"odinger operators in arbitrary signatures (with or without gradings), providing a general KK-theoretic framework for the study of index pairings and spectral flow. We provide a general…

K-Theory and Homology · Mathematics 2025-09-30 Koen van den Dungen

In this article we give a comprehensive treatment of a `Clifford module flow' along paths in the skew-adjoint Fredholm operators on a real Hilbert space that takes values in KO${}_{*}(\mathbb{R})$ via the Clifford index of…

K-Theory and Homology · Mathematics 2020-07-01 Chris Bourne , Alan L. Carey , Matthias Lesch , Adam Rennie

We study the relation between spectral flow and index theory within the framework of (unbounded) KK-theory. In particular, we consider a generalised notion of 'Dirac-Schr\"odinger operators', consisting of a self-adjoint elliptic…

K-Theory and Homology · Mathematics 2019-12-18 Koen van den Dungen

The spectral flow is a well-known quantity in spectral theory that measures the variation of spectra about $0$ along paths of selfadjoint Fredholm operators. The aim of this work is twofold. Firstly, we consider homotopy invariance…

Functional Analysis · Mathematics 2019-10-14 Maciej Starostka , Nils Waterstraat

We present a fairly general construction of unbounded representatives for the interior Kasparov product. As a main tool we develop a theory of C^1-connections on operator * modules; we do not require any smoothness assumptions; our…

Operator Algebras · Mathematics 2013-09-12 Jens Kaad , Matthias Lesch

We generalise the even local index formula of Connes and Moscovici to the case of spectral triples for a *-subalgebra \A of a general semifinite von Neumann algebra. The proof is a variant of that for the odd case which appears in Part I.…

Operator Algebras · Mathematics 2007-05-23 Alan L. Carey , John Phillips , Adam Rennie , Fyodor A. Sukochev

We extend the notion of a spectral triple to that of a higher-order relative spectral triple, which accommodates several types of hypoelliptic differential operators on manifolds with boundary. The bounded transform of a higher-order…

K-Theory and Homology · Mathematics 2024-06-05 Magnus Fries

In this paper, we study the convergence of the spectral embeddings obtained from the leading eigenvectors of certain similarity matrices to their population counterparts. We opt to study this convergence in a uniform (instead of average)…

Statistics Theory · Mathematics 2023-04-26 Ruofei Zhao , Songkai Xue , Yuekai Sun

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

We define complexes analogous to Goncharov's complexes for the K-theory of discrete valuation rings of characteristic zero. Under suitable assumptions in K-theory, there is a map from the cohomology of those complexes to the K-theory of the…

Algebraic Geometry · Mathematics 2007-05-23 Amnon Besser , Rob de Jeu

We prove a generalization of the fundamental theorem of algebraic K-theory for Verdier-localizing functors by extending the proof for algebraic K-theory of spaces to the realm of stable $\infty$-categories. The formula behaves much better…

K-Theory and Homology · Mathematics 2023-12-06 Victor Saunier

In [CPR2], we presented a K-theoretic approach to finding invariants of algebras with no non-trivial traces. This paper presents a new example that is more typical of the generic situation. This is the case of an algebra that admits only…

Operator Algebras · Mathematics 2015-05-13 A. L. Carey , A. Rennie , K. Tong

A basic problem in spectral clustering is the following. If a solution obtained from the spectral relaxation is close to an integral solution, is it possible to find this integral solution even though they might be in completely different…

Data Structures and Algorithms · Computer Science 2015-10-20 Ali Kemal Sinop

The spectral flow is an integer-valued homotopy invariant for paths of selfadjoint Fredholm operators. Lesch as well as Pejsachowicz, Fitzpatrick and Ciriza independently showed that it is uniquely characterised by its elementary…

Functional Analysis · Mathematics 2026-03-27 Marek Izydorek , Joanna Janczewska , Maciej Starostka , Nils Waterstraat

We study the logarithmic topological Hochschild homology of ring spectra with logarithmic structures and establish localization sequences for this theory. Our results apply, for example, to connective covers of periodic ring spectra like…

Algebraic Topology · Mathematics 2015-10-20 John Rognes , Steffen Sagave , Christian Schlichtkrull