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Related papers: Linear Density Perturbations in Multifield Coupled…

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We review the results of large scale simulations of noncompact quenched $QED$ which use spectrum and Equation of State calculations to determine the theory's phase diagram, critical indices, and continuum limit. The resulting anomalous…

High Energy Physics - Lattice · Physics 2009-10-22 Mp Lombardo , J. B. Kogut , A. Kocic , K. C. Wang

We check quantitatively the validity of some popular phenomenological approaches of QCD in simple models. Dispersion sum rules are considered within the ladder approximation of a field-theoretic model with OPE given by ordinary loop…

High Energy Physics - Phenomenology · Physics 2008-02-03 A. A. Penin , A. A. Pivovarov

The analogy between the intermittency and scaling in statistical physics is extended to the case of more variables. It is shown that the inclusive densities predicted by the perturbative QCD obey generalized homogeneity principle which…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Wosiek

In this paper, we fully investigate cosmological scenarios in which dark matter is non-minimally coupled to an extra scalar degree of freedom. The interaction is realized by means of conformal and disformal terms in the transformed…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-02 Fabio Chibana , Rampei Kimura , Masahide Yamaguchi , Daisuke Yamauchi , Shuichiro Yokoyama

A method of resummation of truncated perturbation series, related to diagonal Pad\'e approximants but giving results independent of the renormalization scale, was developed more than ten years ago by us with a view of applying it in…

High Energy Physics - Phenomenology · Physics 2015-05-28 Gorazd Cvetič , Reinhart Kögerler

In this brief note we present a set of equations describing the evolution of perturbed scalar fields in a cosmological spacetime with multiple scalar fields. We take into account of the simultaneously excited full metric perturbations in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Hwang

Quintessence, a scalar field model, has been proposed to account for the acceleration of the Universe at present. We discuss how accurately quintessence models are discriminated by future cosmological surveys, which include experiments of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Yoshitaka Takeuchi , Kiyotomo Ichiki , Tomo Takahashi , Masahide Yamaguchi

Bayesian inference is central to modern cosmology, yet comprehensive model comparison and tension quantification remain computationally prohibitive for many researchers. To address this, we release $\texttt{unimpeded}$, a publicly available…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Dily Duan Yi Ong , Will Handley

We explore quintessence models of dark energy which exhibit non-minimal coupling between the dark matter and the dark energy components of the cosmic fluid. The kind of coupling chosen is inspired in scalar-tensor theories of gravity. We…

Astrophysics · Physics 2009-11-13 Tame Gonzalez , Genly Leon , Israel Quiros

In this work we study the growth of cold dark matter density perturbations in the nonlinear regime on a conformally coupled quintessence model in which the background is designed to mimic a $\Lambda$CDM cosmology. The spherical collapse of…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-03 Bruno J. Barros , Tiago Barreiro , Nelson J. Nunes

We study the change of the effective fine structure constant in the cosmological models of a scalar field with a non-vanishing coupling to the electromagnetic field. Combining cosmological data and terrestrial observations we place…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. J. Copeland , N. J. Nunes , M. Pospelov

Multiscale correlation functions in high Reynolds number experimental turbulence, numerical simulations and synthetic signals are investigated. Fusion Rules predictions as they arise from multiplicative, almost uncorrelated, random…

chao-dyn · Physics 2009-10-31 R. Benzi , L. Biferale , G. Ruiz-Chavarria , S. Ciliberto , F. Toschi

We critically examine how well the evolution of large-scale density perturbations is followed in cosmological $N$-body simulations. We first run a large volume simulation and perform a mode-by-mode analysis in three-dimensional Fourier…

Models where the accelerated expansion of our Universe is caused by a quintessence scalar field are reviewed. In the framework of high energy physics, the physical nature of this field is discussed and its interaction with ordinary matter…

Astrophysics · Physics 2009-06-23 Jerome Martin

We investigate the scalar perturbations in a class of spatially covariant gravity theory with a dynamical lapse function. Generally, there are two scalar degrees of freedom due to the presence of the velocity of the lapse function. We treat…

General Relativity and Quantum Cosmology · Physics 2022-08-10 Xue-Zheng Zhu , Yang Yu , Xian Gao

Realistic models of particle physics include many scalar fields. These fields generically have nonminimal couplings to the Ricci curvature scalar, either as part of a generalized Einstein theory or as necessary counterterms for…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-27 David I. Kaiser , Audrey T. Todhunter

We provide a concise review on multi-field inflation and cosmological perturbations. We discuss convenient and physically meaningful bases in terms of which perturbations can be systematically studied. We give formal accounts on the gauge…

General Relativity and Quantum Cosmology · Physics 2017-02-08 Jinn-Ouk Gong

We study the energy level spacing of perturbed conformal minimal models in finite volume, considering perturbations of such models that are massive but not necessarily integrable. We compute their spectrum using a renormalization group…

Statistical Mechanics · Physics 2015-05-18 G. P. Brandino , R. M. Konik , G. Mussardo

We study the growth of linear perturbations induced by a generic causal scaling source as a function of the cosmological parameters $h$, $\Omega^m_0$ and $\Omega^\Lambda_0$. We show that for wavenumbers $k \gsim 0.01 h/Mpc$ the spectrum of…

Astrophysics · Physics 2009-10-31 P. P. Avelino , J. P. M. de Carvalho

I review the linear and second-order perturbation theory in dark energy models with explicit interaction to matter in view of applications to N-body simulations and non-linear phenomena. Several new or generalized results are obtained: the…

Astrophysics · Physics 2009-11-10 Luca Amendola