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Related papers: Phase space observables and isotypic spaces

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This paper is concerned with frame decompositions of $\alpha$-modulation spaces. These spaces can be obtained as coorbit spaces for square-integrable representations of the affine Weyl-Heisenberg group modulo suitable subgroups. The theory…

Functional Analysis · Mathematics 2014-08-22 Peter Balazs , Dominik Bayer , Michael Speckbacher

We obtain several results concerning the concept of isotypic structures. Namely we prove that any field of finite transcendence degree over a prime subfield is defined by types; then we construct isotypic but not isomorphic structures with…

Logic · Mathematics 2025-06-18 Pavel Gvozdevsky

The aim of this paper is twofold. Firstly, we give easy-to-handle criteria to determine whether a given family of subsets of a vector space is a neighbourhood basis of the origin for a complete vector topology. Then, we apply these criteria…

Functional Analysis · Mathematics 2025-02-20 José L. Ansorena , Alejandro Marcos

A combinatorial property of prositive group presentations, called completeness, is introduced, with an effective criterion for recognizing complete presentations, and an iterative method for completing an incomplete presentation. We show…

Group Theory · Mathematics 2007-05-23 Patrick Dehornoy

We study various ways of characterising the quantum optical number and phase as complementary observables.

Quantum Physics · Physics 2009-11-07 Paul Busch , Pekka Lahti , Juha-Pekka Pellonpaa , Kari Ylinen

This paper presents two general criteria to determine spaceability results in the complements of unions of subspaces. The first criterion applies to countable unions of subspaces under specific conditions and is closely related to the…

Functional Analysis · Mathematics 2024-11-15 Gustavo Araújo , Anderson Barbosa , Anselmo Raposo , Geivison Ribeiro

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

In this paper, we study phase retrievable sequences and give a characterization of phase retrievability of a sequence of bounded linear operators on a Hilbert space $H$; in particular, for $H=\ell_2^d(\Bbb{C})$. We also give several…

Functional Analysis · Mathematics 2023-08-29 F. Javadi , M. J. Mehdipour

Defining the observable ${\bf \phi}$ canonically conjugate to the number observable ${\bf N}$ has long been an open problem in quantum theory. The problem stems from the fact that ${\bf N}$ is bounded from below. In a previous work we have…

Quantum Physics · Physics 2007-05-23 Gilad Gour

As a foundation of modern physics, uncertainty relations describe an ultimate limit for the measurement uncertainty of incompatible observables. Traditionally, uncertain relations are formulated by mathematical bounds for a specific state.…

Quantum Physics · Physics 2019-09-18 Jie Xie , Songtao Huang , Li Zhou , Aonan Zhang , Huichao Xu , Man-Hong Yung , Nengkun Yu , Lijian Zhang

We show that there exist informationally incomplete phase space observables such that the Cartesian margins are informationally equivalent with position and momentum. This shows that it is possible to reconstruct the position and momentum…

Quantum Physics · Physics 2015-06-04 Jussi Schultz

The necessary and sufficient conditions for a three-dimensional Riemannian metric to admit a transitive group of isometries are obtained. These conditions are Intrinsic, Deductive, Explicit and ALgorithmic, and they offer an IDEAL labeling…

General Relativity and Quantum Cosmology · Physics 2020-12-04 Joan Josep Ferrando , Juan Antonio Sáez

This paper is concerned with the construction of phase operators, phase states, vector phase states, and coherent states for a generalized Weyl-Heisenberg algebra. This polynomial algebra (that depends on real parameters) is briefly…

Quantum Physics · Physics 2012-10-17 Maurice Robert Kibler , Mohammed Daoud

The theory of holomorphic functions of several complex variables is applied in proving a multidimensional variant of a theorem involving an exponential boundedness criterion for the classical moment problem. A theorem of Petersen concerning…

Quantum Physics · Physics 2009-11-07 Anatolij Dvurecenskij , Pekka Lahti , Kari Ylinen

Noncommutative phase space of an arbitrary dimension is considered. The both of operators coordinates and momenta in noncommutative phase space may be noncommutative. In this paper, we introduce momentum-momentum noncommutativity in…

High Energy Physics - Theory · Physics 2014-03-20 H. Kakuhata , M. Nakamura

Let $G$ be a connected reductive group. We find a necessary and sufficient condition for a quasiaffine homogeneous space of $G$ to be embeddable into an irreducible $G$-module. In addition, for an affine homogeneous space we find a…

Representation Theory · Mathematics 2010-06-03 Ivan V. Losev

We provide general bounds of phase estimation sensitivity in linear two-mode interferometers. We consider probe states with a fluctuating total number of particles. With incoherent mixtures of state with different total number of particles,…

Quantum Physics · Physics 2015-06-22 Luca Pezzè , Philipp Hyllus , Augusto Smerzi

In a recent paper, two multi-representations for the measurable sets in a computable measure space have been introduced, which prove to be topologically complete w.r.t. certain topological properties. In this contribution, we show them…

Computational Complexity · Computer Science 2010-06-03 Yongcheng Wu

The Hilbert spaces for stable scattering states and particles are determined by the representations of the characterizing Euclidean and Poincar\'e group and given, respectively, by the square integrable functions on the momentum 2-spheres…

High Energy Physics - Theory · Physics 2007-05-23 Heinrich Saller

Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements. The existing methods to quantify a phase distribution rely on complex devices and structures. Here we experimentally…

Optics · Physics 2020-03-25 Tengfeng Zhu , Junyi Huang , Zhichao Ruan