English
Related papers

Related papers: Evaluating backreaction with the ellipsoidal colla…

200 papers

Understanding the impact of environment on the formation and evolution of dark matter halos and galaxies is a crucial open problem. Studying statistical correlations in large simulated populations sheds some light on these impacts, but the…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 Corentin Cadiou , Andrew Pontzen , Hiranya V. Peiris , Luisa Lucie-Smith

The molecular evolution that occurs in collapsing prestellar cores is investigated. To model the dynamics, we adopt the Larson-Penston (L-P) solution and analogues with slower rates of collapse. For the chemistry, we utilize the new…

Astrophysics · Physics 2009-11-07 Yuri Aikawa , Nagayoshi Ohashi , Eric Herbst

We investigate the virialization of cosmic structures in the framework of flat FLRW cosmological models, in which the vacuum energy density evolves with time. In particular, our analysis focuses on the study of spherical matter…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 S. Basilakos , M. Plionis , J. Sola

We investigate the cosmological dynamics of interacting dark energy within the framework of $\alpha$-attractor models. Specifically, we analyze the associated autonomous system, focusing on its fixed points that represent dark energy and…

General Relativity and Quantum Cosmology · Physics 2025-12-04 L. K. Duchaniya , B. Mishra , G. Otalora , M. Gonzalez-Espinoza

Large-scale structure has been shown as a promising cosmic probe for distinguishing and constraining dark energy models. Using the growth index parametrization, we obtain an analytic formula for the growth rate of structures in a coupled…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-07 Rafael J. F. Marcondes , Ricardo C. G. Landim , André A. Costa , Bin Wang , Elcio Abdalla

We perform a linear perturbation analysis of expanding shells driven by expansions of HII regions. The ambient gas is assumed to be uniform. As an unperturbed state, we develop a semi-analytic method for deriving the time evolution of the…

Astrophysics of Galaxies · Physics 2015-05-27 Kazunari Iwasaki , Shu-ichiro Inutsuka , Toru Tsuribe

The angular momentum of galaxies is routinely ascribed to a process of tidal torques acting during the early stages of gravitational collapse, and is predicted from the initial mass distribution using second-order perturbation theory and…

Astrophysics · Physics 2009-10-31 Ben Sugerman , F. J. Summers , Marc Kamionkowski

The excursion set approach allows one to estimate the abundance and spatial distribution of virialized dark matter haloes efficiently and accurately. The predictions of this approach depend on how the nonlinear processes of collapse and…

Astrophysics · Physics 2009-11-06 Ravi K. Sheth , Giuseppe Tormen

We calculate merger rates of dark matter haloes using the Extended Press-Schechter approximation (EPS) for the Spherical Collapse (SC) and the Ellipsoidal Collapse (EC) models. Merger rates have been calculated for masses in the range…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-03 Nicos Hiotelis

With the era of precision cosmology upon us, and upcoming surveys expected to further improve the precision of our observations below the percent level, ensuring the accuracy of our theoretical cosmological model is of the utmost…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-30 Hayley J. Macpherson

Feedback loops are essential for regulating cell proliferation and maintaining the delicate balance between cell division and cell death. Thanks to the exact solution of a few simple models of cell growth it is by now clear that stochastic…

Populations and Evolution · Quantitative Biology 2023-03-07 Antonio Francesco Zirattu , Marta Biondo , Matteo Osella , Michele Caselle

We explore the cosmological implications at effective level of matter creation effects in a dissipative fluid for a FLRW geometry; we also perform a statistical analysis for this kind of model. By considering an inhomogeneous Ansatz for the…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe

We evaluate the effect of inhomogeneity energy on the expansion rate of the universe. Our method is to expand to Newtonian order in potential and velocity but to take into account fully nonlinear density inhomogeneities. To linear order in…

Astrophysics · Physics 2009-11-11 E. R. Siegel , J. N. Fry

The Hubble tension may introduce a new course of action to revise the standard $\Lambda$CDM model to unravel dark energy and dark matter physics. The Hubble parameter can be reconstructed by late-time observations of the background…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Hamed Kameli , Shant Baghram

A coarse-grained model of dense hard sphere colloids building on simple notions of particle mobility and spatial coherence is presented and shown to reproduce results of experiments and simulations for key quantities such as the…

Soft Condensed Matter · Physics 2018-07-06 Nikolaj Becker , Paolo Sibani , Stefan Boettcher , Skanda Vivek

Decaying dark matter models generically modify the equation of state around the time of dark matter decay, and this in turn modifies the expansion rate of the Universe through the Friedmann equation. Thus, a priori, these models could solve…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Andreas Nygaard , Emil Brinch Holm , Thomas Tram , Steen Hannestad

We report the first detection of the halo ellipticities of galaxy clusters by applying the halo-shear-shear correlations (HSSC), without the necessity of major axis determination. We use the Fourier\_Quad shear catalog based on the Hyper…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-30 Zhenjie Liu , Jun Zhang , Cong Liu , Hekun Li

An analytical study is taken to investigate the relationship between material softening and structural softening through the use of a model problem in one dimension. With general nonlinear assumptions on the constitutive relations, it turns…

Biological Physics · Physics 2010-07-30 Hui-Hui Dai , Xiaowu Zhu , Zhen Chen

We examine the implementation of Buchert's and Green & Wald's averaging formalisms in exact spherically symmetric and plane symmetric dust-filled cosmological models. We find that, given a cosmological space-time, Buchert's averaging scheme…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Timothy Clifton , Roberto A. Sussman

Analytic models based on spherical and ellipsoidal gravitational collapse have been used to derive the mass functions of dark matter halos and their progenitors (the conditional mass function). The ellipsoidal model generally provides a…

Astrophysics · Physics 2010-12-16 Jun Zhang , Chung-Pei Ma , Onsi Fakhouri