Concept

Conformal cyclic cosmology

Related publications (71)

Technically natural dark energy from Lorentz breaking

We construct a model of dark energy with a technically natural small contribution to cosmic acceleration, i.e. this contribution does not receive corrections from other scales in the theory. The proposed acceleration mechanism appears generically in the lo ...

2011

Non-linear matter power spectrum from Time Renormalisation Group: efficient computation and comparison with one-loop

Julien Lesgourgues, Benjamin Audren

We address the issue of computing the non-linear matter power spectrum on mildly non-linear scales with efficient semi-analytic methods. We implemented M. Pietroni's Time Renormalization Group (TRG) method and its Dynamical 1-Loop (D1L) limit in a numerica ...

2011

The Cosmic Linear Anisotropy Solving System (CLASS). Part II: Approximation schemes

Julien Lesgourgues, Diego Blas Temino

Boltzmann codes are used extensively by several groups for constraining cosmological parameters with Cosmic Microwave Background and Large Scale Structure data. This activity is computationally expensive, since a typical project requires from 104 to 105 Bo ...

2011

Universal Properties of Dark Matter Halos

Alexey Boyarsky, Oleg Ruchayskiy, Igor Tkachev

We discuss the universal relation between density and size of observed dark matter halos that was recently shown to hold on a wide range of scales, from dwarf galaxies to galaxy clusters. Predictions of cold dark matter (Lambda CDM) N-body simulations are ...

2010

Optimising Boltzmann codes for the PLANCK era

Julien Lesgourgues, Jan Hamann

High precision measurements of the Cosmic Microwave Background (CMB) anisotropies, as can be expected from the PLANCK satellite, will require high-accuracy theoretical predictions as well. One possible source of theoretical uncertainty is the numerical err ...

2009

Simulation of the cosmic evolution of atomic and molecular hydrogen in galaxies

Danail Obreschkow

We present a simulation of the cosmic evolution of the atomic and molecular phases of the cold hydrogen gas in about 3x10^7 galaxies, obtained by postprocessing the virtual galaxy catalog produced by De Lucia & Blaizot on the Millennium Simulation of cosmi ...

American Astronomical Society2009

A virtual sky with extragalactic HI and CO lines for the Square Kilometre Array (SKA) and the Atacama Large Millimeter/submillimeter Array (ALMA)

Danail Obreschkow

We present a sky simulation of the atomic HI-emission line and the first 10 rotational CO emission lines of molecular gas in galaxies beyond the Milky Way. The simulated sky field has a comoving diameter of 500 Mpc/h; hence, the actual field-of-view depend ...

American Astronomical Society2009

Cosmological Perturbation Theory

Sylvain Bréchet

Firstly, a dynamical analysis of adiabatic perturbations of a perfect fluid is performed to first-order about a general FLRW background using the 1 + 3 covariant and gauge-invariant formalism. The 1 + 3 covariant analog of the Mukhanov-Sasaki and Grishchuk ...

University of Cambridge2009

Cosmological applications of a wavelet analysis on the sphere

Yves Wiaux, Jason Douglas McEwen

The cosmic microwave background (CMB) is a relic radiation of the Big Bang and as such it contains a wealth of cosmological information. Statistical analyses of the CMB, in conjunction with other cosmological observables, represent some of the most powerfu ...

2007

Global universe anisotropy probed by the alignment of structures in the cosmic microwave background

Pierre Vandergheynst, Yves Wiaux

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the sphere. The analysis ...

2006

Graph Chatbot

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.