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Related papers: Flows on uniform Roe algebras

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We establish uniqueness and structural stability of a class of parallel flows in a 2D straight, infinite channel, under perturbations with either globally or locally bounded Dirichlet integrals. The significant feature of our result is that…

Analysis of PDEs · Mathematics 2026-02-19 Giovanni P. Galdi , Filippo Gazzola , Mikhail V. Korobkov , Xiao Ren , Gianmarco Sperone

We consider the Hamiltonian renormalisation group flow of discretised one-dimensional physical theories. In particular, we investigate the influence the choice of different embedding maps has on the RG flow and the resulting continuum…

General Relativity and Quantum Cosmology · Physics 2023-05-05 Benjamin Bahr , Klaus Liegener

Roe algebras are C*-algebras built using large-scale (or 'coarse') aspects of a metric space (X,d). In the special case that X=G is a finitely generated group and d is a word metric, the simplest Roe algebra associated to (G,d) is…

Operator Algebras · Mathematics 2013-09-24 Jan Spakula , Rufus Willett

We study the cohomological equation $Xu=f$ for smooth locally Hamiltonian flows on compact surfaces. The main novelty of the proposed approach is that it is used to study the regularity of the solution $u$ when the flow has saddle loops,…

Dynamical Systems · Mathematics 2024-03-19 Krzysztof Frączek , Minsung Kim

We initiate the treatment of KMS states on uniform Roe algebras $\mathrm{C}^*_u(X)$ for a class of naturally occurring flows on these algebras. We show that KMS states on $\mathrm{C}^*_u(X)$ always factor through the diagonal operators…

Operator Algebras · Mathematics 2023-09-12 Bruno de Mendonça Braga , Ruy Exel

We propose an abstract framework of a kind of representation theory for $C^*$-flows, i.e., $C^*$-algebras equipped with one-parameter automorphism groups, as a proper generalization of Olshanski's formalism of unitary representation theory…

Operator Algebras · Mathematics 2024-03-01 Yoshimichi Ueda

Spectral flow was first studied by Atiyah and Lusztig, and first appeared in print in the work of Atiyah-Patodi-Singer (APS). For a norm-continuous path of self-adjoint Fredholm operators in the multiplier algebra $\mathcal{M}(\mathcal{B})$…

Operator Algebras · Mathematics 2024-01-12 Ping Wong Ng , Arindam Sutradhar , Cangyuan Wang

We introduce the notion of a generalized flow on a graph with coefficients in a R-representation and show that the module of flows is isomorphic to the first derived functor of the colimit. We generalize Kirchhoff's laws and build an exact…

Category Theory · Mathematics 2023-06-27 A. A. Husainov , H. Calisici

A compact metric space $X$ and a discrete topological acting group $T$ give a flow $(X,T)$. Robert Ellis had initiated the study of dynamical properties of the flow $(X,T)$ via the algebraic properties of its "Enveloping Semigroup" $E(X)$.…

Dynamical Systems · Mathematics 2023-01-03 Anima Nagar , Manpreet Singh

It is well known that in the commutative case, i.e. for $A=C(X)$ being a commutative C*-algebra, compact selfadjoint operators acting on the Hilbert C*-module $H_A$ (= continuous families of such operators $K(x)$, $x\in X$) can be…

funct-an · Mathematics 2015-06-25 V. M. Manuilov

We introduce Neural Conjugate Flows (NCF), a class of neural network architectures equipped with exact flow structure. By leveraging topological conjugation, we prove that these networks are not only naturally isomorphic to a continuous…

Machine Learning · Computer Science 2024-11-14 Arthur Bizzi , Lucas Nissenbaum , João M. Pereira

It is shown that certain quasi-free flows on the Cuntz algebra $O_\infty$ have the Rohlin property and therefore are cocycle-conjugate with each other. This, in particular, shows that any unital separable nuclear purely infinite simple…

Operator Algebras · Mathematics 2007-05-23 Ola Bratteli , Akitaka Kishimoto , Derek W. Robinson

When $\alpha$ is an approximately inner flow on a C$^*$-algebra $A$ and commutes with an automorphism $\gamma$ of $A$ we may extend $\alpha$ to a flow $\bar{\alpha}$ on the crossed product $A\times_\gamma Z$ by setting $\bar{\alpha}_t(U)=U$…

Operator Algebras · Mathematics 2014-10-31 A. Kishimoto

Steady fluid flows have very special topology. In this paper we describe necessary and sufficient conditions on the vorticity function of a 2D ideal flow on a surface with or without boundary, for which there exists a steady flow among…

Symplectic Geometry · Mathematics 2015-11-19 Anton Izosimov , Boris Khesin

We consider flows $(X,T)$, given by actions $(t, x) \to tx$, on a compact metric space $X$ with a discrete $T$ as an acting group. We study a new class of flows - the \textsc{Strongly Rigid} ($ \mathbf {SR} $) \ flows, that are properly…

Dynamical Systems · Mathematics 2021-11-30 Anima Nagar , Manpreet Singh

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

This paper explores the effect of various graphical constructions upon the associated graph $C^*$-algebras. The graphical constructions in question arise naturally in the study of flow equivalence for topological Markov chains. We prove…

Operator Algebras · Mathematics 2016-09-07 Teresa Bates , David Pask

We discuss general properties of perturbative RG flows in AdS with a focus on the treatment of boundary conditions and infrared divergences. In contrast with flat-space boundary QFT, general covariance in AdS implies the absence of…

High Energy Physics - Theory · Physics 2024-03-05 Edoardo Lauria , Michael N. Milam , Balt C. van Rees

We give a definition of the spectral flow for paths of bounded essentially hyperbolic operators on a Banach space. The spectral flow induces a group homomorphism on the fundamental group of every connected component of the space of…

Functional Analysis · Mathematics 2011-03-10 Garrisi Daniele

We study the classification of the pairs $(N, \,X)$ where $N$ is a Stein surface and $X$ is a complete holomorphic vector field with isolated singularities on $N$. We describe the role of transverse sections in the classification of $X$ and…

Complex Variables · Mathematics 2014-07-18 T. Ito , B. Scardua , Y. Yamagishi