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We obtain estimates of several hadron mass ratios, for Wilson quarks in the valence (quenched) approximation, extrapolated to physical quark mass, infinite volume and zero lattice spacing.

High Energy Physics - Lattice · Physics 2009-10-22 F. Butler , H. Chen , A. Vaccarino , J. Sexton , D. Weingarten

We study the accelerated expansion phase of the universe by using the {\textit{kinematic approach}}. In particular, the deceleration parameter $q$ is parametrized in a model-independent way. Considering a generalized parametrization for…

General Relativity and Quantum Cosmology · Physics 2018-10-22 Abdulla Al Mamon , Kazuharu Bamba

Quantum tomography has become a key tool for the assessment of quantum states, processes, and devices. This drives the search for tomographic methods that achieve greater accuracy. In the case of mixed states of a single 2-dimensional…

Quantum Physics · Physics 2021-07-14 Leonardo Zambrano , Luciano Pereira , Sebastian Niklitschek , Aldo Delgado

A cosmological model with perfect fluid and self-interacting quintessence field is considered in the framework of the spatially flat Friedmann-Robertson-Walker (FRW) geometry. By assuming that all physical quantities depend on the volume…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. K. Mak , T. Harko

A quantum theory of multiphase estimation is crucial for quantum-enhanced sensing and imaging and may link quantum metrology to more complex quantum computation and communication protocols. In this letter we tackle one of the key…

The imaginary part of the quantum geometric tensor is the Berry curvature, while the real part is the quantum metric. Dirac fermions derived from a tight-binding model naturally contains a mass term $m(k)$ with parabolic dispersion, $m(k)=$…

Mesoscale and Nanoscale Physics · Physics 2024-11-28 Motohiko Ezawa

We present a universal technique for quantum state estimation based on the maximum-likelihood method. This approach provides a positive definite estimate for the density matrix from a sequence of measurements performed on identically…

Quantum Physics · Physics 2009-10-31 K. Banaszek , G. M. D'Ariano , M. G. A. Paris , M. F. Sacchi

We estimate the teleported and the gained parameters by means of Fisher information in a non-inertial frame. The sender and the receiver share an accelerated maximum or partial entangled state. The estimation degree of these parameters…

Quantum Physics · Physics 2017-03-27 N. Metwally

We solve a continuing controversy when dealing with density fluctuations in open Friedman-Robertson-Walker universes, on the physical relevance of a class of exponential modes. We show explicitly and rigorously that these modes enter the…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Ugo Moschella , Richard Schaeffer

In order to try explaining the present accelerated expansion of the universe, we consider the most complete noncommutativity, of a certain type, in a Friedmann-Robertson-Walker cosmological model, coupled to a perfect fluid. We use the ADM…

General Relativity and Quantum Cosmology · Physics 2021-06-23 G. Oliveira-Neto , L. Fazza Marcon

We propose a quantum-enhanced lidar system to estimate a target's radial velocity which employs squeezed and frequency entangled signal and idler beams. We compare its performance against a classical protocol using a coherent state with the…

Quantum Physics · Physics 2022-12-21 Maximilian Reichert , Roberto Di Candia , Moe Z. Win , Mikel Sanz

We use chiral perturbation theory to study the extrapolations necessary to make physical predictions from lattice QCD data for the electromagnetic form factors of pseudoscalar mesons. We focus on the quark mass, momentum, lattice spacing,…

High Energy Physics - Lattice · Physics 2014-11-17 T. B. Bunton , F. -J. Jiang , B. C. Tiburzi

A recently-proposed technique, called the dimensional expansion, uses the space-time dimension $D$ as an expansion parameter to extract nonperturbative results in quantum field theory. Here we apply dimensional-expansion methods to examine…

High Energy Physics - Theory · Physics 2009-10-22 Carl M. Bender , Stefan Boettcher

The goal of quantum metrology is the exploitation of quantum resources, like entanglement or quantum coherence, in the fundamental task of parameter estimation. Here we consider the question of the estimation of the Unruh temperature in the…

Quantum Physics · Physics 2020-01-27 Danilo Borim , Lucas C. Céleri , Vasileios I. Kiosses

The possibility of using the optimized $\delta$ expansion for studying medium effects on hadronic properties in quark or nuclear matter is investigated. The $\delta$ expansion is employed to study density effects with two commonly used…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. Krein , D. P. Menezes , M. Nielsen , M. B. Pinto

The importance of the energy spectrum of bound states and their restrictions in quantum mechanics due to the different methods have been used for calculating and determining the limit of them. Comparison of Schrodinger-like equation…

Quantum Physics · Physics 2018-07-09 Zahra Bakhshi

We study the quantum Fisher information (QFI) of acceleration, in the open quantum systems, for a two-level atom with the circular motion coupled to a massless scalar field in the Minkowski vacuum without and with a reflecting boundary in…

General Relativity and Quantum Cosmology · Physics 2021-05-05 Zixu Zhao , Shuhang Zhang , Qiyuan Pan , Jiliang Jing

We study the estimation of parameters in a quantum metrology scheme based on entangled many-body Unruh-DeWitt detectors. It is found that the precision for the estimation of Unruh effect can be enhanced via initial state preparations and…

General Relativity and Quantum Cosmology · Physics 2020-02-04 Jieci Wang , Li Zhang , Songbai Chen , Jiliang Jing

We study the performance of a single qubit-laser as a quantum sensor to measure the amplitude and phase of a driving field. By using parameter estimation theory we show that certain suitable field quadratures are optimal observables in the…

Quantum Physics · Physics 2017-07-19 Samuel Fernández-Lorenzo , Diego Porras

We develop techniques to determine the mass scale of invisible particles pair-produced at hadron colliders. We employ the constrained mass variable m_2C, which provides an event-by-event lower-bound to the mass scale given a mass…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alan J. Barr , Graham G. Ross , Mario Serna