Effects of the variation of fundamental constants on Pop III stellar evolution (2009)
Ekstrom, Sylvia, Coc, Alain, Descouvemont, Pierre, Meynet, Georges, Olive, Keith A., Uzan, Jean-Philippe, ...
A variation of the fundamental constants is expected to affect the thermonuclear rates important for stellar nucleosynthesis. In particular, because of the very small resonant energies of Be8 and...
Tests of General Relativity on Astrophysical Scales (2009)
While tested to a high level of accuracy in the Solar system, general relativity is under the spotlight of both theoreticians and observers on larger scales, mainly because of the need to introduce...
The tests of the constancy of the fundamental constants are tests of the local position invariance and thus of the equivalence principle. We summarize the various constraints that have been obtained...
Quantum Corrections to the Cosmological Evolution of Conformally Coupled Fields (2009)
Cembranos, Jose A. R., Olive, Keith A., Peloso, Marco, Uzan, Jean-Philippe
Because the source term for the equations of motion of a conformally coupled scalar field, such as the dilaton, is given by the trace of the matter energy momentum tensor, it is commonly assumed to...
Non-universal scalar-tensor theories and big bang nucleosynthesis (2008)
Coc, Alain, Olive, Keith A., Uzan, Jean-Philippe, Vangioni, Elisabeth
We investigate the constraints that can be set from big-bang nucleosynthesis on two classes of models: extended quintessence and scalar-tensor theories of gravity in which the equivalence principle...
CFHTLS weak-lensing constraints on the neutrino masses (2008)
Tereno, Ismael, Schimd, Carlo, Uzan, Jean-Philippe, Kilbinger, Martin, Vincent, Frederic H., Fu, Liping
We use measurements of cosmic shear from CFHTLS, combined with WMAP-5 cosmic microwave background anisotropy data, baryonic acoustic oscillations from SDSS and 2dFGRS and supernovae data from SNLS...
Cosmic microwave background bispectrum on small angular scales (2008)
Pitrou, Cyril, Uzan, Jean-Philippe, Bernardeau, Francis
This article investigates the non-linear evolution of cosmological perturbations on sub-Hubble scales in order to evaluate the unavoidable deviations from Gaussianity that arise from the non-linear...
Predictions from an anisotropic inflationary era (2008)
Pitrou, Cyril, Pereira, Thiago S., Uzan, Jean-Philippe
This article investigates the predictions of an inflationary phase starting from a homogeneous and anisotropic universe of the Bianchi I type. After discussing the evolution of the background...
Time drift of cosmological redshifts as a test of the Copernican principle (2007)
Uzan, Jean-Philippe, Clarkson, Chris, Ellis, George F. R.
We present the time drift of the cosmological redshift in a general spherically symmetric spacetime. We demonstrate that its observation would allow us to test the Copernican principle and so...
Cosmological Perturbations seeded by Topological Defects: Setting the Initial Conditions (2007)
Nathalie Deruelle, David Langlois, Jean-Philippe Uzan
We consider a perfectly homogeneous and isotropic universe which undergoes a sudden phase transition. If the transition produces topological defects, which we assume, perturbations in the geometry...
Time drift of cosmological redshifts and its variance (2007)
Uzan, Jean-Philippe, Bernardeau, Francis, Mellier, Yannick
The contribution of cosmological perturbations to the time drift of the cosmological redshift is derived. It is shown that the dominant correction arises from the local acceleration of both the...
Theory of cosmological perturbations in an anisotropic universe (2007)
Pereira, Thiago S., Pitrou, Cyril, Uzan, Jean-Philippe
This article describes the theory of cosmological perturbations around a homogeneous and anisotropic universe of the Bianchi I type. Starting from a general parameterisation of the perturbed...
Theory and Numerics of Gravitational Waves from Preheating after Inflation (2007)
Dufaux, Jean Francois, Bergman, Amanda, Felder, Gary N., Kofman, Lev, Uzan, Jean-Philippe
Preheating after inflation involves large, time-dependent field inhomogeneities, which act as a classical source of gravitational radiation. The resulting spectrum might be probed by direct detection...
Weak Lensing of Baryon Acoustic Oscillations (2007)
Vallinotto, Alberto, Dodelson, Scott, Schimd, Carlo, Uzan, Jean-Philippe
Baryon Acoustic Oscillations (BAO) have recently been observed in the distribution of distant galaxies. The height and location of the BAO peak are strong discriminators of cosmological parameters....
Carter, Brandon, Uzan, Jean-Philippe
This article synthesises and extends recent work on the cosmological consequences of dropping the usual Z_2 reflection symmetry postulate in brane world scenarios. It is observed that for a...
Quantization of perturbations during inflation in the 1+3 covariant formalism (2007)
Pitrou, Cyril, Uzan, Jean-Philippe
This note derives the analogue of the Mukhanov-Sasaki variables both for scalar and tensor perturbations in the 1+3 covariant formalism. The possibility of generalizing them to non-flat...
Stability of six-dimensional hyperstring braneworlds (2007)
Ringeval, Christophe, Peter, Patrick, Uzan, Jean-Philippe
We study a six-dimensional braneworld model with infinite warped extra dimensions in the case where the four-dimensional brane is described by a topological vortex of a U(1) symmetry-breaking Abelian...
Gravitational waves generated by second order effects during inflation (2006)
Osano, Bob, Pitrou, Cyril, Dunsby, Peter, Uzan, Jean-Philippe, Clarkson, Chris
The generation of gravitational waves during inflation due to the non-linear coupling of scalar and tensor modes is discussed. Two methods describing gravitational wave perturbations are used and...
This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion on the role of fundamental constants, of their definition and link...
A Dynamical Study of the Friedmann Equations (2006)
Uzan, Jean-Philippe, Lehoucq, Roland
Cosmology is an attracting subject for students but usually difficult to deal with if general relativity is not known. In this article, we first recall the Newtonian derivation of the Friedmann...
Lensing at cosmological scales: a test of higher dimensional gravity (2006)
Uzan, Jean-Philippe, Bernardeau, Francis
Recent developments in gravitational lensing astronomy have paved the way to genuine mappings of the gravitational potential at cosmological scales. We stress that comparing these data with...
New Developments in the Search for the Topology of the Universe (2006)
Uzan, Jean-Philippe, Lehoucq, Roland, Luminet, Jean-Pierre
Multi-connected Universe models with space idenfication scales smaller than the size of the observable universe produce topological images in the catalogs of cosmic sources. In this review, we...
Coupled Variations of Fundamental Couplings and Primordial Nucleosynthesis (2006)
Coc, Alain, Nunes, Nelson J., Olive, Keith A., Uzan, Jean-Philippe, Vangioni, Elisabeth
The effect of variations of the fundamental nuclear parameters on big-bang nucleosynthesis are modeled and discussed in detail taking into account the interrelations between the fundamental...
The acceleration of the universe and the physics behind it (2006)
Using a general classification of dark enegy models in four classes, we discuss the complementarity of cosmological observations to tackle down the physics beyond the acceleration of our universe. We...
Models of inflation with primordial non-Gaussianities (2006)
Bernardeau, Francis, Brunier, Tristan, Uzan, Jean-Philippe
We present a class of models in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which non-Gaussianity is first...
Schimd, Carlo, Tereno, Ismael, Uzan, Jean-Philippe, Mellier, Yannick, Van Waerbeke, Ludovic, Semboloni, Elisabetta, ...
Dark energy can be investigated in two complementary ways, by considering either general parameterizations or physically well-defined models. Following the second route, we explore the constraints on...
Big bang nucleosynthesis constraints on scalar-tensor theories of gravity (2006)
Coc, Alain, Olive, Keith A., Uzan, Jean-Philippe, Vangioni, Elisabeth
We investigate BBN in scalar-tensor theories of gravity with arbitrary matter couplings and self-interaction potentials. We first consider the case of a massless dilaton with a quadratic coupling to...
Martin, Jerome, Schimd, Carlo, Uzan, Jean-Philippe
In scalar-tensor theories of gravity, the equation of state of dark energy, w, can become smaller than -1 without violating any energy condition. The value of w today is tied to the level of...
High order correlation functions for self interacting scalar field in de Sitter space (2005)
Bernardeau, Francis, Brunier, Tristan, Uzan, Jean-Philippe
We present the expressions of the three- and four-point correlation functions of a self interacting light scalar field in a de Sitter spacetime at tree order respectively for a cubic and a quartic...
Finite volume effects for non-Gaussian multi-field inflationary models (2005)
Bernardeau, Francis, Uzan, Jean-Philippe
Models of multi-field inflation exhibiting primordial non-Gaussianity have recently been introduced. This is the case in particular if the fluctuations of a light field scalar field, transverse to...
Inflationary models inducing non-Gaussian metric fluctuations (2005)
Bernardeau, Francis, Uzan, Jean-Philippe
We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which...
Cosmic Strings Lens Phenomenology Revisited (2005)
Bernardeau, Francis, Uzan, Jean-Philippe
We present investigations of lens phenomenological properties of cosmic strings for deep galaxy surveys. General results that have obtained for lineic energy distribution are presented first. We...
Cosmic Strings Lens Phenomenology: Model of Poisson Energy Distribution (2005)
Bernardeau, Francis, Uzan, Jean-Philippe
We present a novel approach for investigating lens phenomenology of cosmic strings in order to elaborate detection strategies in galaxy deep field images. To account for the complexity of the...
The distance duality relation from X-ray and SZ observations of clusters (2005)
Uzan, Jean-Philippe, Aghanim, Nabila, Mellier, Yannick
X-ray and Sunyaev-Zel\'dovich data of clusters of galaxies enable to construct a test of the distance duality relation between the angular and luminosity distances. We argue that such a test on large...
Weak lensing in scalar-tensor theories of gravity (2004)
Schimd, Carlo, Uzan, Jean-Philippe, Riazuelo, Alain
This article investigates the signatures of various models of dark energy on weak gravitational lensing, including the complementarity of the linear and non-linear regimes. It investigates...
Variation of the constants in the late and early universe (2004)
Recent key observational results on the variation of fine structure constant, the proton to electron mass ratio and the gravitational constant are reviewed. The necessity to substantiate the dark...
Constraints on mode couplings and modulation of the CMB with WMAP data (2004)
Prunet, Simon, Uzan, Jean-Philippe, Bernardeau, Francis, Brunier, Tristan
We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation....
The distance duality relation from X-ray and SZ observations of clusters (2004)
Uzan, Jean-Philippe, Aghanim, Nabila, Mellier, Yannick
X-ray and Sunyaev-Zel'dovich data of clusters of galaxies enable to construct a test of the distance duality relation between the angular and luminosity distances. We argue that such a test on large...
Modulated fluctuations from hybrid inflation (2004)
Bernardeau, Francis, Kofman, Lev, Uzan, Jean-Philippe
Inflation universally produces classical almost scale free Gaussian inhomogeneities of any light scalars. Assuming the coupling constants at the time of inflation depend on some light moduli fields,...
The distance duality relation from X-ray and SZ observations of clusters (2004)
Uzan, Jean-Philippe, Aghanim, Nabila, Mellier, Yannick
X-ray and Sunyaev-Zel\'dovich data of clusters of galaxies enable to construct a test of the distance duality relation between the angular and luminosity distances. We argue that such a test on large...
The distance duality relation from X-ray and SZ observations of clusters (2004)
Uzan, Jean-Philippe, Aghanim, Nabila, Mellier, Yannick
X-ray and Sunyaev-Zel\'dovich data of clusters of galaxies enable to construct a test of the distance duality relation between the angular and luminosity distances. We argue that such a test on large...
Finite volume effects for non-Gaussian multi-field inflationary models (2003)
Bernardeau, Francis, Uzan, Jean-Philippe
Models of multi-field inflation exhibiting primordial non-Gaussianity have recently been introduced. This is the case in particular if the fluctuations of a light field scalar field, transverse to...
High order correlation functions for self interacting scalar field in de Sitter space (2003)
Bernardeau, Francis, Brunier, Tristan, Uzan, Jean-Philippe
We present the expressions of the three- and four-point correlation functions of a self interacting light scalar field in a de Sitter spacetime at tree order respectively for a cubic and a quartic...
Cosmic microwave background anisotropies in multi-connected flat spaces (2003)
Riazuelo, Alain, Weeks, Jeffrey, Uzan, Jean-Philippe, Lehoucq, Roland, Luminet, Jean-Pierre
This article investigates the signature of the seventeen multi-connected flat spaces in cosmic microwave background (CMB) maps. For each such space it recalls a fundamental domain and a set of...
`c' is the speed of light, isn't it? (2003)
Ellis, George F. R., Uzan, Jean-Philippe
Theories proposing a varying speed of light have recently been widely promoted under the claim that they offer an alternative way of solving the standard cosmological problems. Recent observational...
Cosmic microwave background constraints on multi-connected spherical spaces (2003)
Uzan, Jean-Philippe, Riazuelo, Alain, Lehoucq, Roland, Weeks, Jeffrey
This article describes the Cosmic Microwave Background anisotropies expected in a closed universe with the topology of a lens space L(p,q) and with density parameter Omega_0 close to 1. It provides...
Eigenmodes of lens and prism spaces (2003)
Lehoucq, Roland, Uzan, Jean-Philippe, Weeks, Jeffrey
Cosmologists are taking a renewed interest in multiconnected spherical 3-mani\-folds (spherical spaceforms) as possible models for the physical universe. To understand the formation of large scale...
WMAP data and the curvature of space (2003)
Uzan, Jean-Philippe, Kirchner, Ulrich, Ellis, George F. R.
Inter alia, the high precision WMAP data on Cosmic Microwave Background Radiation marginally indicate that the universe has positively curved (and hence spherical) spatial sections. In this paper, we...
Stability of six-dimensional hyperstring braneworlds (2003)
Ringeval, Christophe, Peter, Patrick, Uzan, Jean-Philippe
We study a six-dimensional braneworld model with infinite warped extra dimensions in the case where the four-dimensional brane is described by a topological vortex of a U(1) symmetry-breaking Abelian...
High order correlation functions for self interacting scalar field in de Sitter space (2003)
Bernardeau, Francis, Brunier, Tristan, Uzan, Jean-Philippe
We present the expressions of the three- and four-point correlation functions of a self interacting light scalar field in a de Sitter spacetime at tree order respectively for a cubic and a quartic...
Finite volume effects for non-Gaussian multi-field inflationary models (2003)
Bernardeau, Francis, Uzan, Jean-Philippe
Models of multi-field inflation exhibiting primordial non-Gaussianity have recently been introduced. This is the case in particular if the fluctuations of a light field scalar field, transverse to...
High order correlation functions for self interacting scalar field in de Sitter space (2003)
Bernardeau, Francis, Brunier, Tristan, Uzan, Jean-Philippe
We present the expressions of the three- and four-point correlation functions of a self interacting light scalar field in a de Sitter spacetime at tree order respectively for a cubic and a quartic...
Finite volume effects for non-Gaussian multi-field inflationary models (2003)
Bernardeau, Francis, Uzan, Jean-Philippe
Models of multi-field inflation exhibiting primordial non-Gaussianity have recently been introduced. This is the case in particular if the fluctuations of a light field scalar field, transverse to...
Simulating Cosmic Microwave Background maps in multi-connected spaces (2002)
Riazuelo, Alain, Uzan, Jean-Philippe, Lehoucq, Roland, Weeks, Jeffrey
This article describes the computation of cosmic microwave background anisotropies in a universe with multi-connected spatial sections and focuses on the implementation of the topology in standard...
Trans-Planckian Dark Energy? (2002)
Lemoine, Martin, Martin, Jerome, Uzan, Jean-Philippe
It has recently been proposed by Mersini et al. 01, Bastero-Gil and Mersini 02 that the dark energy could be attributed to the cosmological properties of a scalar field with a non-standard dispersion...
Detecting Topology in a Nearly Flat Spherical Universe (2002)
Weeks, Jeffrey, Lehoucq, Roland, Uzan, Jean-Philippe
When the density parameter is close to unity, the universe has a large curvature radius independently of its being hyperbolic, flat, or spherical. Whatever the curvature, the universe may have either...
Inflationary models inducing non-Gaussian metric fluctuations (2002)
Bernardeau, Francis, Uzan, Jean-Philippe
We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which...
Non-Gaussianity in multi-field inflation (2002)
Bernardeau, Francis, Uzan, Jean-Philippe
This article investigates the generation of non-Gaussianity during inflation. In the context of multi-field inflation, we detail a mechanism that can create significant primordial non-Gaussianities...
This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion on the role of fundamental constants, of their definition and link...
Eigenmodes of 3-dimensional spherical spaces and their application to cosmology (2002)
Lehoucq, Roland, Weeks, Jeffrey, Uzan, Jean-Philippe, Gausmann, Evelise, Luminet, Jean-Pierre
This article investigates the computation of the eigenmodes of the Laplacian operator in multi-connected three-dimensional spherical spaces. General mathematical results and analytical solutions for...
Gradient formula for linearly self-interacting branes (2002)
Carter, Brandon, Battye, Richard A., Uzan, Jean-Philippe
The computation of long range linear self-interaction forces in string and higher dimensional brane models requires the evaluation of the gradients of regularised values of divergent self-interaction...
Eigenmodes of Lens and Prism Spaces (2002)
Lehoucq, Roland, Uzan, Jean-Philippe, Weeks, Jeffrey
Cosmologists are taking a renewed interest in multiconnected spherical 3-manifolds (spherical spaceforms) as possible models for the physical universe. To understand the formation of large scale...
Inflationary models inducing non-Gaussian metric fluctuations (2002)
Bernardeau, Francis, Uzan, Jean-Philippe
We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which...
Inflationary models inducing non-Gaussian metric fluctuations (2002)
Bernardeau, Francis, Uzan, Jean-Philippe
We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which...
Dimming of Supernovae by Photon-Pseudoscalar Conversion and the Intergalactic Plasma (2001)
Deffayet, Cédric, Harari, Diego, Uzan, Jean-Philippe, Zaldarriaga, Matias
Recently Csaki, Kaloper and Terning (hep-ph/0111311) suggested that the observed dimming of distant type Ia supernovae may be a consequence of mixing of the photons with very light axions. We point...
The stress-energy tensor for trans-Planckian cosmology (2001)
Lemoine, Martin, Lubo, Musongela, Martin, Jerome, Uzan, Jean-Philippe
This article presents the derivation of the stress-energy tensor of a free scalar field with a general non-linear dispersion relation in curved spacetime. This dispersion relation is used as a...
A Dynamical Study of the Friedmann Equations (2001)
Uzan, Jean-Philippe, Lehoucq, Roland
Cosmology is an attracting subject for students but usually difficult to deal with if general relativity is not known. In this article, we first recall the Newtonian derivation of the Friedmann...
Cosmological observations in scalar-tensor quintessence (2001)
Riazuelo, Alain, Uzan, Jean-Philippe
The framework for considering the astronomical and cosmological observations in the context of scalar-tensor quintessence in which the quintessence field also accounts for a time dependence of the...
Topological Lensing in Spherical Spaces (2001)
Gausmann, Evelise, Lehoucq, Roland, Luminet, Jean-Pierre, Uzan, Jean-Philippe, Weeks, Jeffrey
This article gives the construction and complete classification of all three-dimensional spherical manifolds, and orders them by decreasing volume, in the context of multiconnected universe models...
Simulated gravity without true gravity in asymmetric brane-world scenarios (2001)
Carter, Brandon, Uzan, Jean-Philippe, Battye, Richard A., Mennim, Andrew
This article investigates asymmetric brane-world scenarios in the limit when the bulk gravity is negligible. We show that, even when true self gravity is negligible, local mass concentrations will be...
Einstein equations for an asymmetric brane-world (2001)
Battye, Richard A., Carter, Brandon, Mennim, Andrew, Uzan, Jean-Philippe
We consider a brane-world of co-dimension one without the reflection symmetry that is commonly imposed between the two sides of the brane. Using the coordinate-free formalism of the Gauss-Codacci...
Carter, Brandon, Uzan, Jean-Philippe
This article synthesises and extends recent work on the cosmological consequences of dropping the usual Z_2 reflection symmetry postulate in brane world scenarios. It is observed that for a...
Lensing at cosmological scales: a test of higher dimensional gravity (2000)
Uzan, Jean-Philippe, Bernardeau, Francis
Recent developments in gravitational lensing astronomy have paved the way to genuine mappings of the gravitational potential at cosmological scales. We stress that comparing these data with...
Cosmic Strings Lens Phenomenology Revisited (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present investigations of lens phenomenological properties of cosmic strings for deep galaxy surveys. General results that have obtained for lineic energy distribution are presented first. We...
Twin paradox and space topology (2000)
Uzan, Jean-Philippe, Luminet, Jean-Pierre, Lehoucq, Roland, Peter, Patrick
If space is compact, then a traveller twin can leave Earth, travel back home without changing direction and find her sedentary twin older than herself. We show that the asymmetry between their...
New Developments in the Search for the Topology of the Universe (2000)
Uzan, Jean-Philippe, Lehoucq, Roland, Luminet, Jean-Pierre
Multi-connected Universe models with space idenfication scales smaller than the size of the observable universe produce topological images in the catalogs of cosmic sources. In this review, we...
Limits of crystallographic methods for detecting space topology (2000)
Lehoucq, Roland, Uzan, Jean-Philippe, Luminet, Jean-Pierre
We investigate to what extent the cosmic crystallographic methods aimed to detect the topology of the universe using catalogues of cosmic objects would be damaged by various observational...
Skewness as a probe of non-Gaussian initial conditions (2000)
Durrer, Ruth, Juszkiewicz, Roman, Kunz, Martin, Uzan, Jean-Philippe
We compute the skewness of the matter distribution arising from non-linear evolution and from non-Gaussian initial perturbations. We apply our result to a very generic class of models with...
Quintessence and Gravitational Waves (2000)
Riazuelo, Alain, Uzan, Jean-Philippe
We investigate some aspects of quintessence models with a non-minimally coupled scalar field and in particular we show that it can behave as a component of matter with $-3 \lesssim P/\rho \lesssim...
Cosmic Strings Lens Phenomenology: Model of Poisson Energy Distribution (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present a novel approach for investigating lens phenomenology of cosmic strings in order to elaborate detection strategies in galaxy deep field images. To account for the complexity of the...
Cosmic Strings Lens Phenomenology: General Properties of Distortion Fields (2000)
Uzan, Jean-Philippe, Bernardeau, Francis
We reconsider the general properties of gravitational lensing effects induced by cosmic string systems, taking into account their equation of state and motion equations. We explicitly show that the...
Photon mixing in universes with large extra-dimensions (2000)
Deffayet, Cedric, Uzan, Jean-Philippe
In presence of a magnetic field, photons can mix with any particle having a two-photon vertex. In theories with large compact extra-dimensions, there exists a hierachy of massive Kaluza-Klein...
Cosmic Strings Lens Phenomenology Revisited (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present investigations of lens phenomenological properties of cosmic strings for deep galaxy surveys. General results that have obtained for lineic energy distribution are presented first. We...
Cosmic Strings Lens Phenomenology: Model of Poisson Energy Distribution (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present a novel approach for investigating lens phenomenology of cosmic strings in order to elaborate detection strategies in galaxy deep field images. To account for the complexity of the...
Cosmic Strings Lens Phenomenology Revisited (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present investigations of lens phenomenological properties of cosmic strings for deep galaxy surveys. General results that have obtained for lineic energy distribution are presented first. We...
Cosmic Strings Lens Phenomenology: Model of Poisson Energy Distribution (2000)
Bernardeau, Francis, Uzan, Jean-Philippe
We present a novel approach for investigating lens phenomenology of cosmic strings in order to elaborate detection strategies in galaxy deep field images. To account for the complexity of the...
A New Crystallographic Method for Detecting Space Topology (1999)
Uzan, Jean-Philippe, Lehoucq, Roland, Luminet, Jean-Pierre
Multi-connected universe models with space identification scales smaller than the size of the observable universe produce topological images of cosmic sources. We generalise to locally hyperbolic...
Cosmological scaling solutions of non-minimally coupled scalar fields (1999)
We study the existence and stability of cosmological scaling solutions of a non-minimally coupled scalar field evolving in either an exponential or inverse power law potential. We show that for...
Topological lens effects in universes with non-Euclidean compact spatial sections (1998)
Lehoucq, R., Luminet, Jean-Pierre, Uzan, Jean-Philippe
Universe models with compact spatial sections smaller than the observable universe produce a topological lens effect. Given a catalog of cosmic sources, we estimate the number of topological images...
Uzan, Jean-Philippe, Deruelle, Nathalie, Riazuelo, Alain
We consider a perfectly homogeneous, isotropic and spatially flat universe which undergoes a sudden phase transition producing topological defects. We assume that these defects form a coherent...
The No-defect Conjecture: Cosmological Implications (1998)
When the topology of the universe is non trivial, it has been shown that there are constraints on the network of domain walls, cosmic strings and monopoles. I generalize these results to textures and...
Conservation Laws and Cosmological Perturbations in Curved Universes (1998)
Uzan, Jean-Philippe, Deruelle, Nathalie, Turok, Neil
When working in synchronous gauges, pseudo-tensor conservation laws are often used to set the initial conditions for cosmological scalar perturbations, when those are generated by topological defects...
Conservation Laws for Cosmological Perurbations (1998)
Deruelle, Nathalie, Uzan, Jean-Philippe
We briefly recall the problem of defining conserved quantities such as energy in general relativity, and the solution by introducing a symmetric background. We apply the general formalism to...
Dynamics of Relativistic Interacting Gases : from a Kinetic to a Fluid Description (1998)
Starting from a microscopic approach, we develop a covariant formalism to describe a set of interacting gases. For that purpose, we model the collision term entering the Boltzmann equation for a...
Cosmological Perturbations seeded by Topological Defects: Setting the Initial Conditions (1997)
Deruelle, Nathalie, Langlois, David, Uzan, Jean-Philippe
We consider a perfectly homogeneous and isotropic universe which undergoes a sudden phase transition. If the transition produces topological defects, which we assume, perturbations in the geometry...
Integral Constraints On cosmological Perturbations and their Energy (1996)
Deruelle, Nathalie, Katz, Joseph, Uzan, Jean-Philippe
We show the relation between Traschen's integral equations and the energy, and ``position of the centre of mass'', of the matter perturbations in a Robertson-Walker spacetime. When the perturbations...
The no-defect conjecture in cosmic crystallography (1996)
Uzan, Jean-Philippe, Peter, Patrick
The topology of space is usually assumed simply connected, but could be multi-connected. We review in the latter case the possibility that topological defects arising at high energy phase transitions...