English
Related papers

Related papers: Quintessence or Phoenix?

200 papers

It is shown that the absence of an objective existence of the results of quantum measurements cannot be proved by known experiments. There are also general arguments confirming this conclusion.

Quantum Physics · Physics 2019-05-28 Alexander Belinsky

We study the perturbations on both "radial" and "angular" components of the quintessence with an internal abelian and non-abelian symmetry. The properties of the perturbation on the "radial" component depend on the specific potential of the…

Astrophysics · Physics 2009-11-10 Xin-zhou Li , Jian-gang Hao , Dao-jun Liu , Xiang-hua Zhai

Modern scientific cosmology pushes the boundaries of knowledge and the knowable. This is prompting questions on the nature of scientific knowledge. A central issue is what defines a 'good' model. When addressing global properties of the…

History and Philosophy of Physics · Physics 2018-12-12 Martin Sahlén

We study the dynamics of a quintessence model based on two interacting scalar fields. The model can account for the (recent) accelerated expansion of the Universe suggested by astronomical observations. Acceleration can be permanent or…

Astrophysics · Physics 2010-05-28 M. C. Bento , O. Bertolami , N. C. Santos

A constructive realization of Skyrme's conjecture that an effective pion mass ``may arise as a self consistent quantal effect'' based on an ab initio quantum treatment of the Skyrme model is presented. In this quantum mechanical Skyrme…

Nuclear Theory · Physics 2008-11-26 A. Acus , E. Norvaisas , D. O. Riska

In this article, we derive a unique procedure for quantum state estimation from a simple, self-evident principle: an experimentalist's estimate of the quantum state generated by an apparatus should be constrained by honesty. A skeptical…

Quantum Physics · Physics 2007-05-23 Robin Blume-Kohout , Patrick Hayden

As an alternative to the popular parametrisations of the dark energy equation of state, we construct a quintessence model where the scalar field has a linear dependence on the number of e-folds. Constraints on more complex models are…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-17 Vitor da Fonseca , Tiago Barreiro , Nelson J. Nunes

We present an approach to estimate the operational distinguishability between an entangled state and any separable state directly from measuring an entanglement witness. We show that this estimation also implies bounds on a variety of other…

Quantum Physics · Physics 2024-04-01 Liang-Liang Sun , Xiang Zhou , Armin Tavakoli , Zhen-Peng Xu , Sixia Yu

We study the convergence properties of state estimates of an oscillating qubit being monitored by a sequence of \textit{discrete}, unsharp measurements. Our method derives a differential equation determining the evolution of the estimation…

Quantum Physics · Physics 2017-05-31 Humairah Bassa , Lajos Diósi , Thomas Konrad , Hermann Uys

We derive new approximations for quintessence solutions that are simpler and an order of magnitude more accurate than anything available in the literature, which from an observational perspective \emph{makes numerical calculations…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Artur Alho , Claes Uggla

Gibbs states are familiar from statistical mechanics, yet their use is not limited to that domain. For instance, they also feature in the maximum entropy reconstruction of quantum states from incomplete measurement data. Outside the…

Quantum Physics · Physics 2011-07-04 Jochen Rau

We test the cosmological implications of a varying absolute magnitude of Type Ia supernovae using the Pantheon compilation, by reconstructing different phenomenological approaches that could justify a varying absolute magnitude, but also…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-11 Domenico Sapone , Savvas Nesseris , Carlos A. P. Bengaly

The possibility of reconstructing the dark energy equation of state from variations in the fine structure constant is investigated for a class of models where the quintessence field is non-minimally coupled to the electromagnetic field. For…

Astrophysics · Physics 2009-11-10 N. J. Nunes , James E. Lidsey

We explore the cosmological consequences of the recently released Union2 sample of 557 Type Ia supernovae (SNIa). Combining this latest SNIa dataset with the Cosmic microwave background (CMB) anisotropy data from the Wilkinson Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Shuang Wang , Xiao-Dong Li , Miao Li

Our knowledge of the Universe remains discovery-led: in the absence of adequate physics-based theory, interpretation of new results requires a scientific methodology. Commonly, scientific progress in astrophysics is motivated by the…

Astrophysics · Physics 2015-05-13 Gerard Gilmore

We present an Effective Field Theory based reconstruction of quintessence models of dark energy directly from cosmological data. We show that current cosmological data possess enough constraining power to test several quintessence model…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 Minsu Park , Marco Raveri , Bhuvnesh Jain

We address several estimation problems in quantum optics by means of the maximum-likelihood principle. We consider Gaussian state estimation and the determination of the coupling parameters of quadratic Hamiltonians. Moreover, we analyze…

Quantum Physics · Physics 2009-11-06 G. Mauro D'Ariano , Matteo G. A. Paris , Massimiliano F. Sacchi

I argue that, contrary to the standard view, one cannot understand the structure and nature of our knowledge in physics without an analysis of the way that observers (and, more generally, measuring instruments and experimental arrangements)…

History and Philosophy of Physics · Physics 2020-06-05 Erik Curiel

We obtain constraints on quintessence models from magnitude-redshift measurements of 176 type Ia Supernovae. The considered quintessence models are ordinary quintessence, with Ratra-Peebles and SUGRA potentials, and extended quintessence…

Astrophysics · Physics 2009-11-10 Paolo Caresia , Sabino Matarrese , Lauro Moscardini

We show, by explicit examples, that the Jaynes inference scheme based on maximization of entropy can produce inseparable states even if there exists a separable state compatible with the measured data. It can lead to problems with…

Quantum Physics · Physics 2008-02-03 Ryszard Horodecki , Michal Horodecki , Pawel Horodecki