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We refute the widely held belief that the quantum weak value necessarily pertains to weak measurements. To accomplish this, we use the transverse position of a beam as the detector for the conditioned von Neumann measurement of a system…

Quantum Physics · Physics 2013-01-16 J. Dressel , A. N. Jordan

Using convex Grothendieck fibrations, we characterize the von Neumann entropy as a functor from finite-dimensional non-commutative probability spaces and state-preserving *-homomorphisms to real numbers. Our axioms reproduce those of Baez,…

Quantum Physics · Physics 2022-03-22 Arthur J. Parzygnat

We develop a version of quantum mechanics that can handle nonassociative algebras of observables and which reduces to standard quantum theory in the traditional associative setting. Our algebraic approach is naturally probabilistic and is…

Quantum Physics · Physics 2024-05-10 Peter Schupp , Richard J. Szabo

Calder\'on-Zygmund theory has been traditionally developed on metric measure spaces satisfying additional regularity properties. In the lack of good metrics, we introduce a new approach for general measure spaces which admit a Markov…

Functional Analysis · Mathematics 2019-07-18 Marius Junge , Tao Mei , Javier Parcet , Runlian Xia

In this paper, we use the tools of nonabelian duality to formulate and prove a far-reaching generalization of the Stone-von Neumann Theorem to modular representations of actions and coactions of locally compact groups on elementary $…

Operator Algebras · Mathematics 2022-06-22 Lucas Hall , Leonard Huang , John Quigg

From the viewpoint of higher dimensional Auslander-Reiten theory, we introduce a new class of finite dimensional algebras of global dimension n, which we call n-representation infinite. They are a certain analog of representation infinite…

Representation Theory · Mathematics 2012-05-08 Martin Herschend , Osamu Iyama , Steffen Oppermann

The decompositions of an element of a finite von Neumann algebra into the sum of a normal operator plus an s.o.t.-quasinilpotent operator, obtained using the Haagerup--Schultz hyperinvariant projections, behave well with respect to…

Operator Algebras · Mathematics 2013-10-10 Ken Dykema , Fedor Sukochev , Dmitriy Zanin

In recent years, many new developments in theoretical physics, and in practical applications rely on different techniques of noncommutative algebras. In this review, we introduce the basic concepts and techniques of noncommutative physics…

High Energy Physics - Theory · Physics 2023-06-08 Shi-Dong Liang , Matthew J. Lake

We prove that the relative commutant of a diffuse von Neumann subalgebra in a hyperbolic group von Neumann algebra is always injective. It follows that any non-injective subfactor in a hyperbolic group von Neumann algebra is non-Gamma and…

Operator Algebras · Mathematics 2007-05-23 Narutaka Ozawa

We show that certain C*-algebras which have been studied among others by Arzumanian, Vershik, Deaconu, and Renault in connection to a measure preserving transformation of a measure space and/or to a covering map of a compact space are…

Operator Algebras · Mathematics 2007-05-23 R. Exel , A. Vershik

In this paper we set up a representation theorem for tracial gauge norms on finite von Neumann algebras satisfying the weak Dixmier property in terms of Ky Fan norms. Examples of tracial gauge norms on finite von Neumann algebras satisfying…

Operator Algebras · Mathematics 2008-04-29 Junsheng Fang , Don Hadwin , Eric Nordgren , Junhao Shen

For a von Neumann algebra M on a Hilbert space, A. Connes has constructed a module S and a derivation of M into S, such that M is approximately finite dimensional if and only if that derivation is inner. The paper contains a generalization…

funct-an · Mathematics 2008-02-03 Erik Christensen , Allan M. Sinclair

The representation theory of deformed oscillator algebras, defined in terms of an arbitrary function of the number operator~$N$, is developed in terms of the eigenvalues of a Casimir operator~$C$. It is shown that according to the nature of…

q-alg · Mathematics 2008-02-03 C. Quesne , N. Vansteenkiste

The goal of this paper is to prove Riemann-Roch type theorems for Deligne-Mumford algebraic stacks. To this end, we introduce a "cohomology with coefficients in representations" and a Chern character, and we prove a…

Algebraic Geometry · Mathematics 2007-05-23 B. Toen

Noncommutative functions are graded functions between sets of square matrices of all sizes over two vector spaces that respect direct sums and similarities. They possess very strong regularity properties (reminiscent of the regularity…

Functional Analysis · Mathematics 2020-05-20 Dmitry Kaliuzhnyi-Verbovetskyi , Leonard Stevenson , Victor Vinnikov

We address a Jordan version of Johnson theorem on (associative) algebras of quotients, namely whether a strongly nonsingular (the Jordan version of nonsingularity) has a von Neumann regular algebra of quotients. Although the answer is…

Rings and Algebras · Mathematics 2020-08-18 Fernando Montaner

Let H be a subgroup of some locally compact group G. Assume H is approximable by discrete subgroups and G admits neighborhood bases which are "almost-invariant" under conjugation by finite subsets of H. Let $m: G \to \mathbb{C}$ be a…

Classical Analysis and ODEs · Mathematics 2014-07-10 Martijn Caspers , Javier Parcet , Mathilde Perrin , Éric Ricard

Reduced HNN extensions of von Neumann algebras (as well as $C^*$-algebras) will be introduced, and their modular theory, factoriality and ultraproducts will be discussed. In several concrete settings, detailed analysis on them will be also…

Operator Algebras · Mathematics 2019-05-21 Yoshimichi Ueda

Let $\M$ be a finite von Neumann algebra acting on a Hilbert space $\H$ and $\AA$ be a transitive algebra containing $\M'$. In this paper we prove that if $\AA$ is 2-fold transitive, then $\AA$ is strongly dense in $\B(\H)$. This implies…

Operator Algebras · Mathematics 2007-07-30 Junsheng Fang , Don Hadwin , Mohan Ravichandran

Expanding on previous work of the author, we initiate the model theoretic study of W$^*$-dynamical systems. We axiomatize continuous weight-preserving group actions of $G$ on von Neumann algebras for $G$ a given locally compact Hausdorff…

Operator Algebras · Mathematics 2025-12-02 Jananan Arulseelan