401 citations · 3.6k across the 126 of their papers we have counts for
40 papers · 1 filter
Propagators in Lagrangian space
Francis Bernardeau, Patrick Valageas
It has been found recently that propagators, e.g. the cross-correlation spectra of the cosmic fields with the initial density field, decay exponentially at large-k in an Eulerian d…
Expansion schemes for gravitational clustering: computing two-point and three-point functions
P. Valageas
We describe various expansion schemes that can be used to study gravitational clustering. Obtained from the equations of motion or their path-integral formulation, they provide sev…
Using the Zeldovich dynamics to test expansion schemes
Patrick Valageas
We apply various expansion schemes that may be used to study gravitational clustering to the simple case of the Zeldovich dynamics. Using the well-known exact solution of the Zeldo…
Cosmology with Weak Lensing Surveys
D. Munshi, P. Valageas, L. Van Waerbeke +1
Weak gravitational lensing is responsible for the shearing and magnification of the images of high-redshift sources due to the presence of intervening matter. The distortions are d…
Large-N expansions applied to gravitational clustering
Patrick Valageas
We develop a path-integral formalism to study the formation of large-scale structures in the universe. Starting from the equations of motion of hydrodynamics (single-stream approxi…
Relaxation of a 1-D gravitational system
Patrick Valageas
We study the relaxation towards thermodynamical equilibrium of a 1-D gravitational system. This OSC model shows a series of critical energies where new equilibria appear a…
How many SNeIa do we need to detect the effect of weak lensing ?
Dipak Munshi, Patrick Valageas
We show that as many as 4000 SNeIa may be required to detect the effect of weak lensing on their flux distribution with a high level of significance. However, if the intrinsic SNeI…
Thermodynamics and dynamics of a 1-D gravitational system
Patrick Valageas
We describe a one-dimensional self-gravitating system derived from the problem of large-scale structure formation in cosmology. Considering small times so that the expansion can be…
Do measurements of the one-point distribution of aperture-mass improve constraints on cosmology ?
Dipak Munshi, Patrick Valageas
We study the possibility of using the entire probability distribution function (PDF) of the aperture mass Map and its related cumulative probability distribution function (CPDF) to…
Cosmological Constraints from Weak Lensing Surveys
Dipak Munshi, Patrick Valageas
Focusing on the well motivated aperture mass statistics $\Map$, we study the possibility of constraining cosmological parameters using future space based SNAP class weak lensing mi…
Cosmology with Weak Lensing Surveys
Dipak Munshi, Patrick Valageas
Weak gravitational lensing surveys measure the distortion of the image of distant sources due to the deflections of light rays by the fluctuations of the gravitational potential al…
Covariance of Weak Lensing Observables
Dipak Munshi, Patrick Valageas
Analytical expressions for covariances of weak lensing statistics related to the aperture mass $\Map$ are derived for realistic survey geometries such as SNAP for a range of smooth…
On Cross-correlating Weak Lensing Surveys
Dipak Munshi, Patrick Valageas
The present generation of weak lensing surveys will be superseded by surveys run from space with much better sky coverage and high level of signal to noise ratio, such as SNAP. How…
Evolution of the Cosmological Density Distribution Function: A New Analytical Model
Patrick Valageas, Dipak Munshi
The one-point probability distribution function (pdf) of the large-scale density field is an important tool to follow the evolution of cosmological structures. In this paper we pre…
On the estimation of gravity-induced non-Gaussianities from weak lensing surveys
Patrick Valageas, Dipak Munshi, Andrew J. Barber
We study various measures of weak lensing distortions in future surveys, taking into account the noise arising from the finite survey size and the intrinsic ellipticity of galaxies…
Weak lensing shear and aperture-mass from linear to non-linear scales
Dipak Munshi, Patrick Valageas, Andrew J. Barber
In this paper we describe the predictions for the smoothed weak lensing shear and aperture-mass of two simple analytical models of the density field: the minimal tree-model and the…
A new approach to gravitational clustering: a path-integral formalism and large-N expansions
P. Valageas
We show that the formation of large-scale structures through gravitational instability in the expanding universe can be fully described through a path-integral formalism. We derive…
From linear to non-linear scales: analytical and numerical predictions for the weak lensing convergence
Andrew J. Barber, Dipak Munshi, Patrick Valageas
Weak lensing convergence can be used directly to map and probe the dark mass distribution in the universe. Building on earlier studies, we recall how the statistics of the converge…
Analytical Predictions for Statistics of Cosmic Shear: Tests Against Simulations
Patrick Valageas, Andrew J. Barber, Dipak Munshi
Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies…
The phase-diagram of the IGM and the entropy floor of groups and clusters: are clusters born warm?
P. Valageas, R. Schaeffer, J. Silk
We point out that two problems of observational cosmology, the facts i) that > 60% of the baryonic content of the universe is not observed at z=0 and ii) that the properties of sma…
Transients from Zel'dovich initial conditions
P. Valageas
We investigate the error implied by the use of the Zel'dovich approximation to set up the initial conditions at a finite redshift zi in numerical simulations. Using a steepest-desc…
Dynamics of gravitational clustering V. Subleading corrections in the quasi-linear regime
P. Valageas
We investigate the properties of the standard perturbative expansions which describe the early stages of the dynamics of gravitational clustering. We show that for hierarchical sce…
Dynamics of gravitational clustering IV. The probability distribution of rare events
P. Valageas
Using a non-perturbative method developed in a previous article (paper II) we investigate the tails of the probability distribution of the overdensity within spherical cel…
Dynamics of gravitational clustering III. The quasi-linear regime for some non-Gaussian initial conditions
P. Valageas
Using a non-perturbative method developed in a previous work (paper II), we derive the probability distribution of the density contrast within spherical cells in the quasi…