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Related papers: On the structure of covariant phase observables

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Covariant phase observables are obtained by defining simple conditions for mappings from the set of phase wave functions (unit vectors of the Hardy space) to the set of phase probability densities. The existence of phase probability density…

Quantum Physics · Physics 2015-06-26 Juha-Pekka Pellonpaa

In this paper we investigate the coupling properties of pairs of quadrature observables, showing that, apart from the Weyl relation, they share the same coupling properties as the position-momentum pair. In particular, they are…

Quantum Physics · Physics 2015-05-14 Pekka Lahti , Juha-Pekka Pellonpaa

Coherent-state representations are a standard tool to deal with continuous-variable systems, as they allow one to efficiently visualize quantum states in phase space. Here, we work out an alternative basis consisting of monomials on the…

Quantum Physics · Physics 2024-06-05 A. Z. Goldberg , A. B. Klimov , G. Leuchs , L. L. Sanchez-Soto

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

Covariant phase difference observables are determined in two different ways, by a direct computation and by a group theoretical method. A characterization of phase difference observables which can be expressed as difference of two phase…

Quantum Physics · Physics 2015-06-26 T. Heinonen , P. Lahti , J. -P. Pellonpaa

Combining elements of twistor-space, phase space and Clifford algebras, we propose a framework for the construction and quantization of certain (quadric) varieties described by Lorentz-covariant multivector coordiantes. The correspondent…

High Energy Physics - Theory · Physics 2018-04-11 Mauricio Valenzuela

The general formalism of quantum mechanics for the description of statistical experiments is briefly reviewed, introducing in particular position and momentum observables as POVM characterized by their covariance properties with respect to…

Quantum Physics · Physics 2009-10-27 Bassano Vacchini

We describe all the localization observables of a quantum particle in a one-dimensional box in terms of sequences of unit vectors in a Hilbert space. An alternative representation in terms of positive semidefinite complex matrices is…

Quantum Physics · Physics 2015-06-26 G. Cassinelli , E. De Vito , P. Lahti , J. -P. Pellonpaa

We covariantize calculations over the manifold of phase space, establishing Stokes' theorem for differential cross sections and providing new definitions of familiar observable properties like infrared and collinear safety. Through the…

High Energy Physics - Phenomenology · Physics 2020-11-25 Andrew J. Larkoski , Tom Melia

The structure of covariant instruments is studied and a general structure theorem is derived. A detailed characterization is given to covariant instruments in the case of an irreducible representation of a locally compact group.

Mathematical Physics · Physics 2009-10-16 Claudio Carmeli , Teiko Heinosaari , Alessandro Toigo

The forms of the generalized quantities that we have recently introduced are dependent on the phase of the probability amplitudes for spin-projection measurements. In this paper, we show explicitly that changing the phase gives different…

Quantum Physics · Physics 2007-05-23 Habatwa Vincent Mweene

We interpret the probabilistic notion of unimodularity for measures on the space of rooted locally finite connected graphs in terms of the theory of measured equivalence relations. It turns out that the right framework for this consists in…

Probability · Mathematics 2015-12-29 Vadim A. Kaimanovich

Using a recent result of Albini et al. to represent quantum homodyne tomography in terms of a single observable (as a normalized positive operator measure) we construct a generalized Markov kernel which transforms (the measurement outcome…

Quantum Physics · Physics 2015-05-13 Pekka Lahti , Juha-Pekka Pellonpää

Countable $\mathcal{L}$-structures $\mathcal{N}$ whose isomorphism class supports a permutation invariant probability measure in the logic action have been characterized by Ackerman-Freer-Patel to be precisely those $\mathcal{N}$ which have…

Logic · Mathematics 2026-02-18 Clinton Conley , Colin Jahel , Aristotelis Panagiotopoulos

This article primarily aims to unify the various formalisms of multivariate coefficients of variation, leveraging advanced concepts of generalized means, whether weighted or not, applied to the eigenvalues of covariance matrices. We…

Instrumentation and Detectors · Physics 2024-03-13 Elise Colin , Razvigor Ossikovski

The moment operators of a semispectral measure having the structure of the convolution of a positive measure and a semispectral measure are studied, with paying attention to the natural domains of these unbounded operators. The results are…

Quantum Physics · Physics 2009-11-13 Jukka Kiukas , Pekka Lahti , Kari Ylinen

We propose a general procedure for estimating the variance-covariance matrix of two-step estimates of structural parameters in latent variable models. The method is partially simulation-based, in that it includes drawing simulated values of…

Methodology · Statistics 2025-07-23 Roberto Di Mari , Jouni Kuha

We show that coorbit spaces can be characterized in terms of arbitrary phase-space covers, which are families of phase-space multipliers associated with partitions of unity. This generalizes previously known results for time-frequency…

Functional Analysis · Mathematics 2015-04-27 José Luis Romero

Stochastic dynamics is generated by a matrix of transition probabilities. Certain eigenvectors of this matrix provide observables, and when these are plotted in the appropriate multi-dimensional space the phases (in the sense of phase…

Statistical Mechanics · Physics 2007-11-08 B. Gaveau , L. S. Schulman

It is shown that the simplest multiplicative random complex matrix model generalizes the large-N phase structure found in the unitary case: A perturbative regime is joined to a nonperturbative regime at a point of nonanalyticity.

High Energy Physics - Lattice · Physics 2010-01-21 Robert Lohmayer , Herbert Neuberger , Tilo Wettig
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