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Related papers: Joint measurability through Naimark's theorem

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We consider first-order differential operators with locally bounded measurable coefficients on vector bundles with measurable coefficient metrics. Under a mild set of assumptions, we demonstrate the equivalence between the essential…

Functional Analysis · Mathematics 2019-07-04 Lashi Bandara , Hemanth Saratchandran

In this work we explore the self-adjointness of the GUP-modified momentum and Hamiltonian operators over different domains. In particular, we utilize the theorem by von-Newmann for symmetric operators in order to determine whether the…

High Energy Physics - Theory · Physics 2015-05-26 Venkat Balasubramanian , Saurya Das , Elias C. Vagenas

In the article, we find new dilatation results on non-commutative $L_p$ spaces. We prove that any selfadjoint, unital, positive measurable Schur multiplier on some $B(L^2(\Sigma))$ admits, for all $1\leq p<\infty$, an invertible isometric…

Functional Analysis · Mathematics 2022-09-20 Charles Duquet

Density operators are one of the key ingredients of quantum theory. They can be constructed in two ways: via a convex sum of 'doubled kets' (i.e. mixing), and by tracing out part of a 'doubled' two-system ket (i.e. dilation). Both…

Quantum Physics · Physics 2018-03-05 Maaike Zwart , Bob Coecke

A Positive Operator Valued Measure (POVM) is a map $F:\mathcal{B}(X)\to\mathcal{L}_s^+(\mathcal{H})$ from the Borel $\sigma$-algebra of a topological space $X$ to the space of positive self-adjoint operators on a Hilbert space…

Functional Analysis · Mathematics 2018-04-03 Roberto Beneduci

A theory of joint nonideal measurement of incompatible observables is used in order to assess the relative merits of quantum tomography and certain measurements of generalized observables, with respect to completeness of the obtained…

Quantum Physics · Physics 2007-05-23 Willem M. de Muynck

Density operators are one of the key ingredients of quantum theory. They can be constructed in two ways: via a convex sum of `doubled kets' (i.e. mixing), and by tracing out part of a `doubled' two-system ket (i.e. dilation). Both…

Quantum Physics · Physics 2017-04-10 Maaike Zwart , Bob Coecke

A commutative POV measure $F$ with real spectrum is characterized by the existence of a PV measure $E$ (the sharp reconstruction of $F$) with real spectrum such that $F$ can be interpreted as a randomization of $E$. This paper focuses on…

Mathematical Physics · Physics 2010-05-18 Roberto Beneduci

This talk is a survey of the question of joint measurability of coexistent observables and its is based on the monograph Operational Quantum Physics [1] and on the papers [2,3,4].

Quantum Physics · Physics 2007-05-23 Pekka Lahti

We consider symmetry operators a from the group ring C[S_N] which act on the Hilbert space H of the 1D spin-1/2 Heisenberg magnetic ring with N sites. We investigate such symmetry operators a which are self-adjoint (in a sence defined in…

Combinatorics · Mathematics 2015-05-14 Bernd Fiedler

We propose a scheme that can realize a class of positive-operator-valued measures (POVMs) by performing a sequence of projective measurements on the original system, in the sense that for an arbitrary input state the probability…

Quantum Physics · Physics 2007-05-23 Guoming Wang , Mingsheng Ying

Observables of a quantum system, described by self-adjoint operators in a von Neumann algebra or affiliated with it in the unbounded case, form a conditionally complete lattice when equipped with the spectral order. Using this…

Mathematical Physics · Physics 2013-12-06 Andreas Doering , Barry Dewitt

A finite set of quantum observables (positive operator valued measures) is called compatible if these observables are marginals of a some observable, called a joint observable of them. For a given set of compatible observables, their joint…

Quantum Physics · Physics 2019-01-23 Teiko Heinosaari , Yui Kuramochi

Local operators in the bulk of AdS can be represented as smeared operators in the dual CFT. We show how to construct these bulk observables by requiring that the bulk operators commute at spacelike separation. This extends our previous work…

High Energy Physics - Theory · Physics 2011-06-08 Daniel Kabat , Gilad Lifschytz , David A. Lowe

Three notions of complementarity - operational, probabilistic, and value complementarity - are reanalysed with respect to the question of joint measurements and compared with reference to some examples of canonically conjugate observables.…

Quantum Physics · Physics 2011-01-04 P. Busch , P. J. Lahti

In this article, the self-adjoint extensions of symmetric operators satisfying anti-commutation relations are considered. It is proven that an anti-commutative type of the Glimm-Jaffe-Nelson commutator theorem follows. Its application to an…

Functional Analysis · Mathematics 2014-01-28 Toshimitsu Takaesu

Quantum measurements can be interpreted as a generalisation of probability vectors, in which non-negative real numbers are replaced by positive semi-definite operators. We extrapolate this analogy to define a generalisation of doubly…

Quantum Physics · Physics 2023-05-11 Leonardo Guerini , Alexandre Baraviera

We address the generalized measurement of the two-boson operator $Z_\gamma= a_1 + \gamma a_2^\dag$ which, for $|\gamma|^2 \neq 1$, is not normal and cannot be detected by a joint measurement of quadratures on the two bosons. We explicitly…

Quantum Physics · Physics 2007-06-12 Matteo G A Paris , Giulio Landolfi , Giulio Soliani

We calculate experimentally measurable signatures of quantum correlations in a coupled molecular dimer that strongly interacts with its vibrational environment. We investigate intensity and mode-resolved photon coincidences for different…

Quantum Physics · Physics 2025-12-16 Priyankar Banerjee , Adam Burgess , Julian Wiercinski , Moritz Cygorek , Erik M. Gauger

Let $A$ be a $\nu$-vector of self-adjoint, pairwise commuting operators and $B$ a bounded operator of class $C^{n_0}(A)$. We prove a Taylor-like expansion of the commutator $[B,f(A)]$ for a large class of functions $f\colon\mathbm{R}^\nu…

Functional Analysis · Mathematics 2012-12-07 Morten Grud Rasmussen