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Related papers: Generalized CCR Flows

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We show that the Markov semigroup obtained by Floricel in [Flo08] compressing the $E_0$-semigroup of Skeide [Ske06], does not consist of endomorphisms. It, therefore, cannot be the tail flow of an $E_0$-semigroup. As a corollary of our…

Operator Algebras · Mathematics 2013-11-20 Michael Skeide

A new infinitesimal characterization of completely positive but not necessarily homomorphic Markov flows from a C^*-algebra to bounded operators on the boson Fock space over L^2(R) is given. Contrarily to previous characterizations, based…

Quantum Physics · Physics 2007-05-23 L. Accardi , S. V. Kozyrev

Product systems have been originally introduced to classify E$_0$-semigroups on type I factors by Arveson. We develop the classification theory of E$_0$-semigroups on a general von Neumann algebra and the dilation theory of…

Operator Algebras · Mathematics 2019-04-23 Yusuke Sawada

We analyze $f$-frequently hypercyclic, $q$-frequently hypercyclic ($q> 1$) and frequently hypercyclic $C_{0}$-semigroups ($q=1$) defined on complex sectors, working in the setting of separable infinite-dimensional Fr\'echet spaces. Some…

Functional Analysis · Mathematics 2018-08-06 Belkacem Chaouchi , Marko Kosti\' c , Stevan Pilipovi\' c , Daniel Velinov

In this note we study the generation of $C_0$-semigroups by first order differential operators on $\mathrm{L}^p (\mathbb{R}_+,\mathbb{C}^{\ell})\times \mathrm{L}^p ([0,1],\mathbb{C}^{m})$ with general boundary conditions. In many cases we…

Analysis of PDEs · Mathematics 2021-10-19 Klaus-Jochen Engel , Marjeta Kramar Fijavž

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

Weierstrass semigroups are well-known along the literature. We present a new family of non-Weierstrass semigroups which can be written as an intersection of Weierstrass semigroups. In addition, we provide methods for calculating…

Algebraic Geometry · Mathematics 2020-05-27 J. I. García-García , D. Marín-Aragón , F. Torres , A. Vigneron-Tenorio

'A semigroup is completely regular if and only if it is a union of groups'- an analogue of this structure theorem of completely regular semigroup has been obtained in the setting of seminearrings in [[16], Mukherjee (Pal) et al., Semigroup…

Rings and Algebras · Mathematics 2025-07-10 Rajlaxmi Mukherjee , Tuhin Manna , Kamalika Chakraborty , Sujit Kumar Sardar

This article is a survey of the author's research. It consists of three sections concerned three kinds of cohomologies of semigroups. Section 1 considers `classic' cohomology as it was introduced by Eilenberg and MacLane. Here the attention…

Rings and Algebras · Mathematics 2008-03-05 B. V. Novikov

A one-parameter generalization of the hierarchy of negative flows is introduced for integrable hierarchies of evolution equations, which yields a wider (new) class of non-evolutionary integrable nonlinear wave equations. As main results,…

Exactly Solvable and Integrable Systems · Physics 2017-01-24 Stephen C. Anco , Shahid Mohammad , Thomas Wolf , Chunrong Zhu

W. Arveson has described a cocycle conjugacy class $U(\alpha)$ of $E_0$-semigroup $\alpha$ on B(H) which is a factor of type $\rm I$. Under some conditions on $\alpha$, there is a $E_0$-semigroup $\beta \in U(\alpha)$ being a flow of shifts…

Operator Algebras · Mathematics 2007-05-23 G. G. Amosov

Let $P$ be a closed convex cone in $\mathbb{R}^{d}$ which we assume to be spanning and pointed i.e. $P-P=\mathbb{R}^{d}$ and $P \cap -P=\{0\}$. In this article, we consider CCR flows over $P$ associated to isometric representations that…

Operator Algebras · Mathematics 2019-07-12 Anbu Arjunan , S. Sundar

This paper presents the complete classification of E_0-semigroups by product systems in the case of von Neumann correspondences, and under countability assumptions in the case of C*-correspondences.

Operator Algebras · Mathematics 2016-07-29 Michael Skeide

Impulsive semiflows modeled by continuous flows and continuous impulsive functions, defined over an impulsive region, are piecewise continuous semiflows with piecewise smooth trajectories. In this paper we contribute to the topological…

Dynamical Systems · Mathematics 2026-04-01 Mario Bessa , Jaqueline Siqueira , Maria Joana Torres , Paulo Varandas

Product systems are the classifying structures for semigroups of endomorphisms of B(H), in that two $E_0$-semigroups are cocycle conjugate iff their product systems are isomorphic. Thus it is important to know that every abstract product…

Operator Algebras · Mathematics 2007-05-23 William Arveson

We continue the work started in parts (I) and (II). In this part we classify which continuous type A quivers are derived equivalent and introduce the new continuous cluster category with E-clusters, which are a generalization of clusters.…

Representation Theory · Mathematics 2025-06-19 Kiyoshi Igusa , Job D. Rock , Gordana Todorov

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 derive general Novikov-Morse type inequalities in a Conley type framework for flows carrying cocycles, therefore generalizing our results in [FJ2] derived for integral cocycle. The condition of carrying a cocycle expresses the…

Geometric Topology · Mathematics 2007-05-23 Huijun Fan , Juergen Jost

Based on the study of non-invertible symmetries, we propose there exist infinitely many new renormalization group flows between Virasoro minimal models $\mathcal{M}(kq + I, q) \to\mathcal{M}(kq-I, q)$ induced by $\phi_{(1,2k+1)}$. They…

High Energy Physics - Theory · Physics 2025-06-19 Takahilo Tanaka , Yu Nakayama

We generalise to signed graphs a classical result of Tutte [Canad. J. Math. 8 (1956), 13--28] stating that every integer flow can be expressed as a sum of characteristic flows of circuits. In our generalisation, the r\^ole of circuits is…

Combinatorics · Mathematics 2014-07-22 Edita Macajova , Martin Skoviera