Zur Algebra der Funktionaloperationen und Theorie der normalen Operatoren

  title={Zur Algebra der Funktionaloperationen und Theorie der normalen Operatoren},
  author={John von Neumann},
  journal={Mathematische Annalen},
  • J. Neumann
  • Published 1 December 1930
  • Mathematics
  • Mathematische Annalen

Complex powers of abstract pseudodifferential operators

Under suitable assumptions, we show that the abstract pseudodifferential operators introduced by Connes and Moscovici possess complex powers that belong to this class of operators. We analyse several


. We use standard notation and terminology of Banach space theory,see J.Lindenstrauss and L.Tzafriri [LT]. By a subspace we mean a linear, but notnecessarily closed, subspace. We also assume some

W*-algebras and noncommutative integration

This text is a detailed overview of the theories of W*-algebras and noncommutative integration, up to the Falcone-Takesaki theory of noncommutative Lp spaces over arbitrary W*-algebras, and its

Relative annihilators and relative commutants in non‐selfadjoint operator algebras

We extend von Neumann's Double Commutant Theorem to the setting of non‐selfadjoint operator algebras 𝒜, while restricting the notion of commutants of a subset 𝒮 of 𝒜 to those operators in 𝒜 that

a Unitary Invariant in Riemannian Geometry

We introduce an invariant of Riemannian geometry which measures the relative position of two von Neumann algebras in Hilbert space, and which, when combined with the spectrum of the Dirac operator,

Berger-Coburn-Lebow representation for pure isometric representations of product system over $\mathbb N^2_0$

. We obtain Berger-Coburn-Lebow (BCL) representation for pure isometric covariant representation of product system over N 20 . Then the corresponding unitary invariants are studied and the

Snowmass White Paper: The Quest to Define QFT

This article provides a review of the literature on rigorous definitions and constructions in Quantum Field Theory, spanning the period of seven decades. Comparing with the ideas and constructions

Rota-Baxter $C^{\ast}$-algebras

This paper introduces the notion of Rota-Baxter C∗-algebras. Here a RotaBaxter C∗-algebra is a C∗-algebra with a Rota-Baxter operator. Symmetric Rota-Baxter operators, as special cases of Rota-Baxter

Quantum tomography and the quantum Radon transform

<p style='text-indent:20px;'>A general framework for the tomographical description of states, that includes, among other tomographical schemes, the classical Radon transform, quantum state tomography

Pairwise coexistence of effects versus coexistence

  • W. Stulpe
  • Mathematics
    Journal of Physics: Conference Series
  • 2020
The concept of coexistence of quantum mechanical effects is reviewed. We distinguish between coexistence and pairwise coexistence and give an example showing the non-equivalence the two concepts. A