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The accelerated expansion of the universe is a rather established fact in cosmology and many different models have been proposed as a viable explanation. Many of these models are based on the standard general relativistic framework of…

General Relativity and Quantum Cosmology · Physics 2016-05-20 N. Nazari-Pooya , M. Malekjani , F. Pace , D. Mohammad-Zadeh Jassur

We calculate the power spectrum of density fluctuations in the statistical non-equilibrium field theory for classical, microscopic degrees of freedom to first order in the interaction potential. We specialise our result to cosmology by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-07 Matthias Bartelmann , Felix Fabis , Daniel Berg , Elena Kozlikin , Robert Lilow , Celia Viermann

Great attention is given to the first star formation and the epoch of reionization as main targets of planned large radio interferometries (e.g. Square Kilometre Array). Recently, it is claimed that the supersonic relative velocity between…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-03 Shinsuke Asaba , Kiyotomo Ichiki , Hiroyuki Tashiro

Estimation of the covariance structure of spatial processes is of fundamental importance in spatial statistics. In the literature, several non-parametric and semi-parametric methods have been developed to estimate the covariance structure…

Methodology · Statistics 2016-11-06 Shu Yang , Zhengyuan Zhu

In this work we derive the evolution equation for the density contrast considering open system cosmology, where the influence of adiabatic particle production process on the dynamic of a homogeneous and isotropic is investigated within a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. de Campos , N. Tomimura

We study structure formation using relativistic cosmological linear perturbation theory in the presence of intrinsic and relative (with respect to matter) non-adiabatic dark energy perturbations. For different dark energy models we assess…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Hermano Velten , Raquel Fazolo

Understanding the formation of binary and multiple stellar systems largely comes down to studying the circumstances for the fragmentation of a condensing core during the first stages of the collapse. However, the probability of…

Solar and Stellar Astrophysics · Physics 2015-02-11 Evangelia Ntormousi , Patrick Hennebelle

Application of nonparametric and semiparametric regression techniques to high-dimensional time series data has been hampered due to the lack of effective tools to address the ``curse of dimensionality.'' Under rather weak conditions, we…

Statistics Theory · Mathematics 2009-09-29 Li Wang , Lijian Yang

Structure formation provides a strong test of any cosmic acceleration model because a successful dark energy model must not inhibit {\black or overpredict} the development of observed large-scale structures. Traditional approaches to…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. Prescod-Weinstein , N. Afshordi

We present a new fast and efficient approach to model structure formation with Augmented Lagrangian Perturbation Theory (ALPT). Our method is based on splitting the displacement field into a long and a short-range component. The long-range…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Francisco-Shu Kitaura , Steffen Heß

The pseudo-spectral method is proposed for following the evolution of density and velocity fluctuations at the weakly non-linear stage in the expanding universe with a good accuracy. In this method, the evolution of density and velocity…

Astrophysics · Physics 2017-02-01 Naoteru Gouda

A recently proposed schematic model for the non--linear rheology of dense colloidal dispersions is compared to flow curves measured in suspensions that consist of thermosensitive particles. The volume fraction of this purely repulsive model…

Soft Condensed Matter · Physics 2009-11-11 Matthias Fuchs , Matthias Ballauff

Spatial structure can arise in spatial point process models via a range of mechanisms, including neighbour-dependent directionally biased movement. This spatial structure is neglected by mean-field models, but can have important effects on…

Cell Behavior · Quantitative Biology 2019-11-06 Michael J Plank

A variety of researchers have successfully obtained the parameters of low dimensional diffusion models using the data that comes out of atomistic simulations. This naturally raises a variety of questions about efficient estimation,…

Statistical Mechanics · Physics 2015-11-06 Christopher P. Calderon

Collapse models are phenomenological models introduced to solve the measurement problem in quantum mechanics. They modify the Schr\"odinger equation by adding non-linear and stochastic terms, which induce the wavefunction collapse in space.…

Quantum Physics · Physics 2025-08-27 Matteo Carlesso , Sandro Donadi

The molecular component of the Galaxy is comprised of turbulent, magnetized clouds, many of which are self-gravitating and form stars. To understand how these clouds' evolution may depend on their level of turbulence, mean magnetization,…

Astrophysics · Physics 2009-10-31 Eve C. Ostriker , Charles F. Gammie , James M. Stone

This work is concerned with the development of a space-time adaptive numerical method, based on a rigorous a posteriori error bound, for a semilinear convection-diffusion problem which may exhibit blow-up in finite time. More specifically,…

Numerical Analysis · Mathematics 2015-02-12 Andrea Cangiani , Emmanuil H. Georgoulis , Irene Kyza , Stephen Metcalfe

Using the classical top-hat profile, we study the non-linear growth of spherically symmetric density perturbation and structure formation in $f(T)$ gravities. In particular, three concrete models, which have been tested against the…

General Relativity and Quantum Cosmology · Physics 2017-03-24 Rui-hui Lin , Xiang-hua Zhai , Xin-zhou Li

When a self-gravitating spherical gas cloud collapses or accretes onto a central mass, the inner region of the cloud develops a density profile $\rho\propto r^{-3/2}$ and the velocity approaches free-fall. We show that in this region,…

Astrophysics · Physics 2009-10-31 Dong Lai , Peter Goldreich

We combine the physics of the ellipsoidal collapse model with the excursion set theory to study the shapes of dark matter halos. In particular, we develop an analytic approximation to the nonlinear evolution that is more accurate than the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Graziano Rossi , Ravi K. Sheth , Giuseppe Tormen