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Related papers: On the noncommutative spectral flow

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In this paper we study spectra and Fredholm properties of Ornstein-Uhlenbeck operators $$\mathcal{L}v(x)=A\triangle v(x)+\langle Sx,\nabla v(x)\rangle+Df(v_{\star}(x))v(x),\,x\in\mathbb{R}^d,\,d\geqslant 2$$ where…

Analysis of PDEs · Mathematics 2016-12-23 Wolf-Jürgen Beyn , Denny Otten

Modular flow is a symmetry of the algebra of observables associated to spacetime regions. Being closely related to entanglement, it has played a key role in recent connections between information theory, QFT and gravity. However, little is…

High Energy Physics - Theory · Physics 2021-02-03 Johanna Erdmenger , Pascal Fries , Ignacio A. Reyes , Christian P. Simon

We present a method for linearising classes of matrix-valued nonlinear partial differential equations with local and nonlocal nonlinearities. Indeed we generalise a linearisation procedure originally developed by P\"oppe based on solving…

Analysis of PDEs · Mathematics 2020-10-05 Anastasia Doikou , Simon J. A. Malham , Ioannis Stylianidis

We give a mathematically rigorous analysis which confirms the surprising results in a recent paper of Benilov, O'Brien and Sazonov about the spectrum of a highly singular non-self-adjoint operator that arises in a problem in fluid…

Spectral Theory · Mathematics 2007-05-23 E B Davies

We argue that there should exist a "noncommutative Fourier transform" which should identify functions of noncommutative variables (say, of matrices of indeterminate size) and ordinary functions or measures on the space of paths. Some…

Quantum Algebra · Mathematics 2007-05-23 M. Kapranov

The spectral flow is ubiquitous in the physics of soliton-fermion interacting systems. We study the spectral flows related to a continuous deformation of background soliton solutions, which enable us to develop insight into the emergence of…

High Energy Physics - Theory · Physics 2024-05-09 Yuki Amari , Nobuyuki Sawado , Shintaro Yamamoto

In this paper, we define an analytical index for a continuous family of Fredholm operators parameterized by a topological space $\mathbb{X}$ into a Hilbert space $H,$ as a sequence of integers, extending naturally the usual definition of…

Spectral Theory · Mathematics 2020-10-28 Mohammed Berkani

We extend the spectral theory of commutative C*-categories to the non full-case, introducing a suitable notion of spectral spaceoid provinding a duality between a category of "non-trivial" *-functors of non-full commutative C*-categories…

Operator Algebras · Mathematics 2025-11-04 Paolo Bertozzini , Roberto Conti , Wicharn Lewkeeratiyutkul , Kasemsun Rutamorn

We show how many classes of partial differential systems with local and nonlocal nonlinearities are linearisable in the sense that they are realisable as Fredholm Grassmannian flows. In other words, time-evolutionary solutions to such…

Analysis of PDEs · Mathematics 2022-01-17 Anastasia Doikou , Simon J. A. Malham , Ioannis Stylianidis , Anke Wiese

We study the spectral properties of a class of many channel Hamiltonians which contains those of systems of particles interacting through k-body and field type forces which do not preserve the number of particles. Our results concern the…

Mathematical Physics · Physics 2008-06-05 Mondher Damak , Vladimir Georgescu

We introduce a semigroup framework for Laplacians on directed hypergraphs, extending the classical heat flow models on graphs and establishing hypergraphs as prototypical models for non-Markovian diffusion. We apply spectral surgery methods…

Dynamical Systems · Mathematics 2025-10-31 Delio Mugnolo

In this paper the concept of unbounded Fredholm operators on Hilbert C*- modules over an arbitrary C*-algebra is discussed and the Atkinson theorem is generalized for bounded and unbounded Feredholm operators on Hilbert C*-modules over…

Operator Algebras · Mathematics 2015-06-26 Assadollah Niknam , Kamran Sharifi

We consider Hamiltonian PDEs that can be split into a linear unbounded operator and a regular non linear part. We consider abstract splitting methods associated with this decomposition where no discretization in space is made. We prove a…

Numerical Analysis · Mathematics 2008-11-26 Erwan Faou , Benoit Grebert , Eric Paturel

The paper gives first quantitative estimates on the modulus of continuity of the spectral measure for weak mixing suspension flows over substitution automorphisms, which yield information about the "fractal" structure of these measures. The…

Dynamical Systems · Mathematics 2014-07-28 Alexander I. Bufetov , Boris Solomyak

We study operator-splitting schemes for approximating Koopman generators of linear semigroups induced by nonlinear flows, a framework originating with Dorroh and Neuberger. Building on ideas of Lie, Kowalewski, and Gr\"{o}bner, we analyze…

Numerical Analysis · Mathematics 2025-12-17 A. Banjara , I. AlJabea , T. Papamarkou , F. Neubrander

We study the spectrum of one dimensional integral operators in bounded real intervals of length $2L$, for value of $L$ large. The integral operators are obtained by linearizing a non local evolution equation for a non conserved order…

Mathematical Physics · Physics 2017-01-16 Enza Orlandi , Carlangelo Liverani

We study the parametrized Hamiltonian action functional for finite-dimensional families of Hamiltonians. We show that the linearized operator for the $L^2$-gradient lines is Fredholm and surjective, for a generic choice of Hamiltonian and…

Symplectic Geometry · Mathematics 2009-09-24 Frédéric Bourgeois , Alexandru Oancea

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

If $A \colon D(A) \subset \mathcal{H} \to \mathcal{H}$ is an unbounded Fredholm operator of index $0$ on a Hilbert space $\mathcal{H}$ with a dense domain $D(A)$, then its spectrum is either discrete or the entire complex plane. This…

Spectral Theory · Mathematics 2025-10-10 Simon Becker , Izak Oltman , Martin Vogel

We propose to build a combinatorial invariant, called the spectral monodromy, from the spectrum of a single non-selfadjoint h-pseudodifferential operator with two degrees of freedom in the semi-classical limit. Our inspiration comes from…

Mathematical Physics · Physics 2015-06-15 Quang Sang Phan