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We propose in this work a practical approach to address the longstanding and challenging problem of quantum separability, leveraging the correlation matrices of generic observables. General separability conditions are obtained by dint of…

Quantum Physics · Physics 2025-05-07 Ma-Cheng Yang , Cong-Feng Qiao

Preconjugate variables X have commutation relations with the energy-momentum P of the respective system which are of a more general form than just the Hamiltonian one. Since they have been proven useful in their own right for finding new…

High Energy Physics - Theory · Physics 2016-12-21 Albert Much , Steffen Pottel , Klaus Sibold

We consider the variational principle in the covariant formulation of modified teleparallel theories with second order field equations. We vary the action with respect to the spin connection and obtain a consistency condition relating the…

General Relativity and Quantum Cosmology · Physics 2017-08-15 Martin Krssak

The teleparallel formulation of gravity theories reveals close structural analogies to electrodynamics, which are more hidden in their usual formulation in terms of the curvature of spacetime. We show how every locally Lorentz invariant…

General Relativity and Quantum Cosmology · Physics 2018-06-05 Manuel Hohmann , Laur Järv , Martin Krššák , Christian Pfeifer

We discuss complementarity relations in a bipartite continuous variable system. Building up from the work done on discrete d-dimensional systems, we prove that for symmetric two-mode states, quantum complementarity relations can be put in a…

Quantum Physics · Physics 2009-11-13 S. Springer , M. Paternostro

A construction of covariant quantum phase observables, for Hamiltonians with a finite number of energy eigenvalues, has been recently given by D. Arsenovic et al. [Phys. Rev. A 85, 044103 (2012)]. For Hamiltonians generating periodic…

Quantum Physics · Physics 2012-11-15 Michael J. W. Hall , David T. Pegg

This paper provides necessary and sufficient conditions for constructing a universal quantum computer over continuous variables. As an example, it is shown how a universal quantum computer for the amplitudes of the electromagnetic field…

Quantum Physics · Physics 2009-10-31 Seth Lloyd , Samuel L. Braunstein

Complete characterization of the state of a quantum system made up of subsystems requires determination of relative phase, because of interference effects between the subsystems. For a system of qubits used as a quantum computer this is…

Quantum Physics · Physics 2013-01-15 E. C. Behrman , J. E. Steck

Variational quantum algorithms (VQAs) are prominent candidates for near-term quantum advantage but lack rigorous guarantees of convergence and generalization. By contrast, quantum phase estimation (QPE) provides provable performance under…

Quantum Physics · Physics 2025-10-09 Tuyen Nguyen , Mária Kieferová

Due to its underlying gauge structure, teleparallel gravity achieves a separation between inertial and gravitational effects. It can, in consequence, describe the isolated gravitational interaction without resorting to the equivalence…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. Aldrovandi , L. C. T. Guillen , J. G. Pereira , K. H. Vu

Classical phase-space variables are normally chosen to promote to quantum operators in order to quantize a given classical system. While classical variables can exploit coordinate transformations to address the same problem, only one set of…

High Energy Physics - Theory · Physics 2020-06-30 John R. Klauder

In this article we propose a `second quantization' scheme especially suitable to deal with non-trivial, highly symmetric phase spaces, implemented within a more general Group Approach to Quantization, which recovers the standard Quantum…

High Energy Physics - Theory · Physics 2016-12-28 M. Calixto , V. Aldaya , M. Navarro

We give a quantum benchmark for teleportation and quantum storage experiments suited for pure and mixed test states. The benchmark is based on the average fidelity over a family of phase-covariant states and certifies that an experiment can…

Quantum Physics · Physics 2009-05-11 J. Calsamiglia , M. Aspachs , R. Munoz-Tapia , E. Bagan

Using the position as an independent variable, and time as the dependent variable, we derive the function ${\cal P}^{(\pm)}$, which generates the space evolution under the potential ${\cal V}(q)$ and Hamiltonian ${\cal H}$. Canonically…

Quantum Physics · Physics 2023-07-31 Marcus W Beims , Arlans JS Lara

A general theory based upon 7 postulates is introduced. The basical notions are theoretical variables that are associated with an observer or with a group of communicating observers. These variables may be accessible or inaccessible. From…

Quantum Physics · Physics 2025-02-12 Inge S. Helland

In a metric variable based Hamiltonian quantization, we give a prescription for constructing semiclassical matter-geometry states for homogeneous and isotropic cosmological models. These "collective" states arise as infinite linear…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Viqar Husain , Oliver Winkler

A study of the $\lambda$- and $N$-atomic configurations under dipolar interaction with $2$ modes of electromagnetic radiation is presented. The corresponding quantum phase diagrams are obtained by means of a variational procedure. Both…

Quantum Physics · Physics 2016-07-06 S. Cordero , O. Castaños , R. López-Peña , E. Nahmad-Achar

For many years coherent states have been a useful tool for understanding fundamental questions in quantum mechanics. Recently, there has been work on developing a consistent way of including constraints into the phase space path integral…

Quantum Physics · Physics 2009-10-30 M. C. Ashworth

Affine coherent states are generated by affine kinematical variables much like canonical coherent states are generated by canonical kinematical variables. Although all classical and quantum formalisms normally entail canonical variables, it…

High Energy Physics - Theory · Physics 2015-05-30 John R. Klauder

Phase is a basic ingredient for quantum states since quantum mechanics uses complex numbers to describe quantum states. In this letter, we introduce a rigorous framework to quantify the phase of quantum states. To do so, we regard phase as…

Quantum Physics · Physics 2023-08-10 Jianwei Xu