English
Related papers

Related papers: Anisotropic separate universe simulations

200 papers

We study the two-point correlation function of density perturbations in a spherically symmetric void universe model which does not employ the Copernican principle. First we solve perturbation equations in the inhomogeneous universe model…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-25 Ryusuke Nishikawa , Chul-Moon Yoo , Ken-ichi Nakao

These lectures deal with our current knowledge of the matter distribution in the universe, focusing on how this is studied via the large-scale structure seen in galaxy surveys. We first assemble the necessary basics needed to understand the…

Astrophysics · Physics 2007-05-23 J. A. Peacock

Traditional N-body methods introduce localised perturbations in the gravitational forces governing their evolution. These perturbations lead to an artificial fragmentation in the filamentary network of the Large Scale Structure, often…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-28 Robert A. Mostoghiu Paun , Darren Croton , Chris Power , Alexander Knebe , Adam J. Ussing , Alan R. Duffy

The presence of complex hierarchical gravitational structures is one of the main features of the observed universe. Here, structure formation is studied both for the standard ($\Lambda \rm CDM$) cosmological model and for the Dirac-Milne…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-02 Giovanni Manfredi , Jean-Louis Rouet , Bruce N. Miller , Gabriel Chardin

Astronomical observations strongly suggest that our universe is now accelerating and contains a substantial admixture of dark vacuum energy. Using numerical simulations to study this newly consolidated cosmological model (with a constant…

Astrophysics · Physics 2009-11-10 Fred C. Adams , Michael T. Busha , August E. Evrard , Risa H. Wechsler

Future galaxy surveys will provide accurate measurements of the matter power spectrum across an unprecedented range of scales and redshifts. The analysis of these data will require one to accurately model the imprint of non-linearities of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Linda Blot , Pier-Stefano Corasaniti , Yann Rasera , Shankar Agarwal

In a landscape of compactifications with different numbers of macroscopic dimensions, it is possible that our universe has nucleated from a vacuum where some of our four large dimensions were compact while other, now compact, directions…

High Energy Physics - Theory · Physics 2012-01-11 Julian Adamek , David Campo , Jens C. Niemeyer

We discuss the effect of the time evolution of extra dimensions on CMB anisotropies and large-scale structure formation. We study the impact of scalar fields in a low-energy effective description of a general class of brane world models on…

Astrophysics · Physics 2009-11-07 C. S. Rhodes , C. van de Bruck , Ph. Brax , A. C. Davis

We present a field-level emulator for large-scale structure, capturing the cosmology dependence and the time evolution of cosmic structure formation. The emulator maps linear displacement fields to their corresponding nonlinear…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Drew Jamieson , Yin Li , Francisco Villaescusa-Navarro , Shirley Ho , David N. Spergel

The theory of structure formation predicts that galaxies form within extended massive dark matter halos built from smaller pieces that collided and merged, resulting in the hierarchy of galaxies, groups, and clusters observed today. Here we…

We investigate the evolution of a universe with a decaying cosmological term (vacuum energy) that is assumed to be a function of the scale factor. In this model, while the cosmological term increases to the early universe, the radiation…

Astrophysics · Physics 2008-11-26 Riou Nakamura , Masa-aki Hashimoto , Kiyotomo Ichiki

A cosmological model with anisotropic dark energy is analyzed. The amount of deviation from isotropy of the equation of state of dark energy, the skewness \delta, generates an anisotropization of the large-scale geometry of the Universe,…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-28 L. Campanelli , P. Cea , G. L. Fogli , L. Tedesco

Metamaterials and metasurfaces are designed by periodically arranged subwavelength geometries, allowing a tailored manipulation of the electromagnetic response of matter. Here, we exploit temporal variations of permittivity inside…

Optics · Physics 2025-09-24 Victor Pacheco-Peña , Nader Engheta

The large scale geometry of the late Universe can be decomposed as R$\times {\Sigma}_3$, where R stands for cosmic time and ${\Sigma}_3$ is the three dimensional spatial manifold. We conjecture that the spatial geometry of the Universe's…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-08 Yassir Awwad , Tomislav Prokopec

Anisotropic cosmological models are constructed in $f(R,T)$ gravity theory to investigate the dynamics of universe concerning the late time cosmic acceleration. Using a more general and simple approach, the effect of the coupling constant…

General Physics · Physics 2018-10-05 B. Mishra , Sankarsan Tarai , S. K. Tripathy

The apparent anisotropies of the galaxy clustering in observable redshift space provide a unique opportunity to simultaneously probe cosmic expansion and gravity on cosmological scales via the Alcock--Paczynski effect and redshift-space…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-25 Yong-Seon Song , Atsushi Taruya , Akira Oka

Understanding the universe is hampered by the elusiveness of its most common constituent, cold dark matter. Almost impossible to observe, dark matter can be studied effectively by means of simulation and there is probably no other research…

In this work we present cosmological N-body simulations of the Local Universe with initial conditions constrained by the Two-Micron Redshift Survey (2MRS) within a cubic volume of 180 Mpc/h side-length centred at the Local Group. We use a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Steffen Heß , Francisco-Shu Kitaura , Stefan Gottloeber

Tides are the main driving force behind the long-term evolution of planetary systems. The associated energy dissipation and momentum exchanges are commonly described by Love numbers, which relate the exciting potential to the tidally…

Earth and Planetary Astrophysics · Physics 2025-02-05 Pierre Auclair-Desrotour , Gwenaël Boué , Baptiste Loire

High-precision cosmological observations have revealed persistent tensions within the standard $\Lambda$CDM paradigm, most notably the discrepancy in the Hubble constant and the lower than predicted amplitude of late-time matter clustering…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-28 Biswajit Pandey