Zobrazeno 1 - 10
of 36
pro vyhledávání: '"Amrutam, Tattwamasi"'
Autor:
Amrutam, Tattwamasi, Jiang, Yongle
Let $G$ be a discrete group. Given unital $G$-$C^*$-algebras $\mathcal{A}$ and $\mathcal{B}$, we give an abstract condition under which every $G$-subalgebra $\mathcal{C}$ of the form $\mathcal{A}\subset \mathcal{C}\subset \mathcal{A}\otimes_{\text{mi
Externí odkaz:
http://arxiv.org/abs/2408.08635
Let $G$ be a locally compact second countable group equipped with an admissible non-degenerate Borel probability measure $\mu$. We generalize the notion of $\mu$-stationary systems to $\mu$-stationary $G$-factor maps $\pi: (X,\nu)\to (Y,\eta)$. For t
Externí odkaz:
http://arxiv.org/abs/2405.17122
Given a dynamical system $(X, \Gamma)$, the corresponding crossed product $C^*$-algebra $C(X)\rtimes_{r}\Gamma$ is called reflecting, when every intermediate $C^*$-algebra $C^*_r(\Gamma)<\mathcal{A} < C(X)\rtimes_{r}\Gamma$ is of the form $\mathcal{A
Externí odkaz:
http://arxiv.org/abs/2404.09803
Autor:
Amrutam, Tattwamasi, Bassi, Jacopo
Publikováno v:
Pacific J. Math. 331 (2024) 1-22
Let $\Gamma$ be a discrete group acting on a compact Hausdorff space $X$. Given $x\in X$, and $\mu\in\text{Prob}(X)$, we introduce the notion of contraction of $\mu$ towards $x$ with respect to unitary elements of a group von Neumann algebra not nece
Externí odkaz:
http://arxiv.org/abs/2403.05948
Given a unital $C(X)$-algebra $A$ discrete group $\Gamma$ and an action $\alpha: \Gamma\to \text{aut}(A)$ which leaves $C(X)$ invariant and such that $C(X)\rtimes_{\alpha,r} \Gamma$ is simple, and a $2$-cocycle $\omega$, we obtain a bijective corresp
Externí odkaz:
http://arxiv.org/abs/2312.07702
Let $B$ be a separable $C^*$-algebra, let $\Gamma$ be a discrete countable group, let $\alpha: \Gamma \to \text{Aut}(B)$ be an action, and let $A$ be an invariant subalgebra. We find certain freeness conditions which guarantee that any intermediate $
Externí odkaz:
http://arxiv.org/abs/2311.01524
Publikováno v:
Journal of Functional Analysis, 2024
We approach the study of sub-von Neumann algebras of the group von Neumann algebra $L\Gamma$ for countable groups $\Gamma$ from a dynamical perspective. It is shown that $L(\Gamma)$ admits a maximal invariant amenable subalgebra. The notion of invari
Externí odkaz:
http://arxiv.org/abs/2309.10494
Let $\Gamma$ be a countable group and $(X, \Gamma)$ a compact topological dynamical system. We study the question of the existence of an intermediate $C^*$-subalgebra $\mathcal{A}$ $$C^{*}_{r}(\Gamma)<\mathcal{A}
Externí odkaz:
http://arxiv.org/abs/2306.14278
Autor:
Amrutam, Tattwamasi, Hartman, Yair
This paper concerns the non-commutative analog of the Normal Subgroup Theorem for certain groups. Inspired by Kalantar-Panagopoulos, we show that all $\Gamma$-invariant subalgebras of $L\Gamma$ and $C^*_r(\Gamma)$ are ($\Gamma$-) co-amenable. The gro
Externí odkaz:
http://arxiv.org/abs/2208.06019
Autor:
Amrutam, Tattwamasi, Jiang, Yongle
We say that a countable discrete group $\Gamma$ satisfies the invariant von Neumann subalgebras rigidity (ISR) property if every $\Gamma$- invariant von Neumann subalgebra $\mathcal{M}$ in $L(\Gamma)$ is of the form $L(\Lambda)$ for some normal subgr
Externí odkaz:
http://arxiv.org/abs/2205.10700