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Related papers: Lueders Theorem for Coherent-State POVMs

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Statistical ensemble formalism of Kim, Mandel and Wolf (J. Opt. Soc. Am. A 4, 433 (1987)) offers a realistic model for characterizing the effect of stochastic non-image forming optical media on the state of polarization of transmittedlight.…

Optics · Physics 2007-06-26 Sudha , A. V. Gopala Rao , A. R. Usha Devi , A. K. Rajagopal

In order to study the "problem of time", Rovelli proposed a model of a two harmonic oscillator system where one of the oscillators can be thought of as a 'clock' for the other oscillator. In this paper we examine a model where the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yoshiaki Ohkuwa

For a time-dependent harmonic oscillator with an inverse squared singular term, we find the generalized invariant using the Lie algebra of $SU(2)$ and construct the number-type eigenstates and the coherent states using the…

Quantum Physics · Physics 2007-05-23 Jung Kon Kim , Sang Pyo Kim

A pair of Hilbert space linear operators $(V_1,V_2)$ is said to be $q$-commutative, for a unimodular complex number $q$, if $V_1V_2=qV_2V_1$. A concrete functional model for $q$-commutative pairs of isometries is obtained. The functional…

Functional Analysis · Mathematics 2022-07-05 Joseph A. Ball , Haripada Sau

Current quantum theories of an elementary free particle assume unitary space inversion and anti-unitary time reversal operators. In so doing robust classes of possible theories are discarded. The present work shows that consistent theories…

Mathematical Physics · Physics 2023-03-06 Giuseppe Nisticò

We study various optimality criteria for quantum observables. Observables are represented as covariant positive operator valued measures and we consider the case when the symmetry group is compact. Phase observables are examined as an…

Quantum Physics · Physics 2009-04-08 Claudio Carmeli , Teiko Heinosaari , Juha-Pekka Pellonpää , Alessandro Toigo

Based on a recent proof of free choices in linking equations to the experiments they describe, I clarify relations among some purely mathematical entities featured in quantum mechanics (probabilities, density operators, partial traces, and…

Quantum Physics · Physics 2014-09-15 John M. Myers

We prove that every bounded, positive, irreducible, stochastically continuous semigroup on the space of bounded, measurable functions which is strong Feller, consists of kernel operators and possesses an invariant measure converges…

Functional Analysis · Mathematics 2012-02-03 Moritz Gerlach , Robin Nittka

Quantum theory combines density matrices, Born probabilities, tensor-product composites, positive-operator-valued measures (POVMs), and quantum channels. In a finite-dimensional causal operational theory, we prove that two postulates…

Quantum Physics · Physics 2026-05-25 Kenji Nakahira

It is well-known in quantum information theory that a positive operator valued measure (POVM) is the most general kind of quantum measurement. Mathematically, a quantum probability is a normalised POVM, namely a function on certain subsets…

Quantum Physics · Physics 2022-12-06 Kyler S. Johnson , Michael J. Kozdron

Quantum coherence is one of the most significant theories in quantum physics. Ordering states with various coherence measures is an intriguing task in quantification theory of coherence. In this paper, we study this problem by use of four…

Quantum Physics · Physics 2018-03-08 Long-Mei Yang , Bin Chen , Shao-Ming Fei , Zhi-Xi Wang

The relativistic equivalent of the Schr\"odinger equation for a two particle bound state having the total angular momentum $S$ is written in the form of a Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P)…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. Micu

It is well known that, in the description of quantum observables, positive operator valued measures (POVMs) generalize projection valued measures (PVMs) and they also turn out be more optimal in many tasks. We show that a commutative POVM…

Quantum Physics · Physics 2011-07-12 Teiko Heinosaari , Juha-Pekka Pellonpää

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

For the models of $N$-body identical harmonic oscillators interacting through potentials of homogeneous degree -2, the unitary operator that transforms a system of time-dependent parameters into that of unit spring constant and unit mass of…

Quantum Physics · Physics 2007-05-23 Dae-Yup Song

A group of symmetric operators are introduced to carry out the separability criterion for bipartite and multipartite quantum states. Every symmetric operator, represented by a symmetric matrix with only two nonzero elements, and their…

Quantum Physics · Physics 2012-12-04 Jie-Hui Huang , Li-Yun Hu , Lei Wang , Shi-Yao Zhu

Inspired by an old idea of von Neumann, we seek a pair of commuting operators X,P which are, in a specific sense, "close" to the canonical non-commuting position and momentum operators, x,p. The construction of such operators is related to…

Quantum Physics · Physics 2009-11-11 J. J. Halliwell

We study the Lie and Noether point symmetries of a class of systems of second-order differential equations with $n$ independent and $m$ dependent variables ($n\times m$ systems). We solve the symmetry conditions in a geometric way and…

Differential Geometry · Mathematics 2016-06-22 Andronikos Paliathanasis , Michael Tsamparlis

We derive the class of covariant measurements which are optimal according to the maximum likelihood criterion. The optimization problem is fully resolved in the case of pure input states, under the physically meaningful hypotheses of…

We study the known coherent states of a quantum harmonic oscillator from the standpoint of the original developed noncommutative integration method for linear partial differential equations. The application of the method is based on the…

Quantum Physics · Physics 2022-11-22 A. I. Breev , A. V. Shapovalov