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Related papers: Decomposability of multiparameter CAR flows

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Recently it is proved in arXiv:1906.05493v1 [math.OA] that CCR flows over convex cones are cocycle conjugate if and only if the associated isometric representations are conjugate. We provide a very short, simple and direct proof of that.…

Operator Algebras · Mathematics 2019-08-02 R. Srinivasan

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

Let $P$ be a pointed, closed convex cone in $\mathbb{R}^d$. We prove that for two pure isometric representations $V^{(1)}$ and $V^{(2)}$ of $P$, the associated CAR flows $\beta^{V^{(1)}}$ and $\beta^{V^{(2)}}$ are cocycle conjugate if and…

Operator Algebras · Mathematics 2023-12-12 C. H. Namitha , S. Sundar

In [8], Arveson proved that a $1$-parameter decomposable product system is isomorphic to the product system of a CCR flow. We show that the structure of a generic decomposable product system, over higher dimensional cones, modulo twists by…

Operator Algebras · Mathematics 2022-12-20 C. H. Namitha , S. Sundar

In this paper using one of the necessary conditions obtained for extendability in [BISSar], we prove that the CAR flows ([Amo01]) on type III factors arising from most quasi-free states are not extendable. As a consequence we find the super…

Operator Algebras · Mathematics 2014-02-04 Panchugopal Bikram

In this paper, we revisit Arveson's characterisation of CCR flows in terms of decomposibility of the product system in the multiparameter context. We show that a multiparameter $E_0$-semigroup is a CCR flow if and only if it is decomposable…

Operator Algebras · Mathematics 2019-12-03 S. Sundar

In this paper we show that the chain recurrent set of a flow of automorphisms on a connected Lie group coincides with the central subgroup of the flow, if the group is decomposable. Moreover, in the decomposable case, the flow satisfies the…

Dynamical Systems · Mathematics 2025-01-07 Adriano Da Silva , Jhon Eddy Pariapaza Mamani

We consider the multiparameter CAR flows and describe its opposite. We also characterize the symmeticity of CAR flows in terms of associated isometric representations.

Operator Algebras · Mathematics 2021-01-05 Anbu Arjunan

We initiate a study of E-semigroups over convex cones. We prove a structure theorem for E-semigroups which leave the algebra of compact operators invariant. Then we study in detail the CCR flows, E$_0$semigroups constructed from isometric…

Operator Algebras · Mathematics 2018-07-31 Anbu Arjunan , R. Srinivasan , S. Sundar

In this paper, we construct uncountably many examples of multiparameter CCR flows, which are not pullbacks of $1$-parameter CCR flows, with index one. Moreover, the constructed CCR flows are type I in the sense that the associated product…

Operator Algebras · Mathematics 2021-08-12 Piyasa Sarkar , S. Sundar

In this note, we exhibit an example of a multiparameter CCR flow which is not cocycle conjugate to its opposite. This is in sharp contrast to the one parameter situation

Operator Algebras · Mathematics 2020-01-03 S. Sundar

A planar set $P$ is said to be cover-decomposable if there is a constant $k=k(P)$ such that every $k$-fold covering of the plane with translates of $P$ can be decomposed into two coverings. It is known that open convex polygons are…

Metric Geometry · Mathematics 2014-03-12 István Kovács , Géza Tóth

The existence of decompositions of the nonlinear integrable systems not only permits us to establish so-called linear superposition solutions but also to derive new nonlinear integrable coupled systems. Restricting our attention to the…

Exactly Solvable and Integrable Systems · Physics 2022-05-18 Xiazhi Hao , S. Y. Lou

We introduce a cohomology theory for spatial super- product systems and compute the $2-$cocycles for some basic examples called as Clifford super-product systems, thereby distinguish them up to isomorphism. This consequently proves that a…

Operator Algebras · Mathematics 2019-07-17 Oliver T. Margetts , R Srinivasan

The 3-Decomposition Conjecture states that every connected cubic graph can be decomposed into a spanning tree, a 2-regular subgraph and a matching. We show that this conjecture holds for the class of connected plane cubic graphs.

Combinatorics · Mathematics 2017-10-31 Arthur Hoffmann-Ostenhof , Tomáš Kaiser , Kenta Ozeki

Suppose a link K in a 3-manifold M is in bridge position with respect to two different bridge surfaces P and Q, both of which are c-weakly incompressible in the complement of K. Then either P and Q can be properly isotoped to intersect in a…

Geometric Topology · Mathematics 2007-05-23 Martin Scharlemann , Maggy Tomova

It is well known that each nonnegative integral flow on a graph can be decomposed into a sum of nonnegative graphic circuit flows, which cannot be further decomposed into nonnegative integral sub-flows. This is equivalent to saying that the…

Combinatorics · Mathematics 2021-06-21 Beifang Chen , Jue Wang , Thomas Zaslavsky

Let $P$ be a closed convex cone in $\mathbb{R}^{n}$. Assume that $P$ is spanning i.e. $P-P=\mathbb{R}^{n}$ and pointed i.e. $P \cap -P=\{0\}$. Let $\alpha:=\{\alpha_{x}:x \in P\}$ be a $\sigma$-weakly continuous family of unital normal…

Operator Algebras · Mathematics 2017-06-14 S. P. Murugan , S. Sundar

An unsplittable multiflow routes the demand of each commodity along a single path from its source to its sink node. As our main result, we prove that in series-parallel digraphs, any given multiflow can be expressed as a convex combination…

Combinatorics · Mathematics 2025-07-22 Mohammed Majthoub Almoghrabi , Martin Skutella , Philipp Warode

Let $G$ be the circulant graph $C_n(S)$ with $S\subseteq\{ 1,\ldots,\left \lfloor\frac{n}{2}\right \rfloor\}$ and let $\Delta$ be its independence complex. We describe the well-covered circulant graphs with 2-dimensional $\Delta$ and…

Commutative Algebra · Mathematics 2018-07-17 Francesco Romeo , Giancarlo Rinaldo
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