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Related papers: Geodesic-light-cone coordinates and the Bianchi I …

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Most of cosmological observables are light-propagated. I will present coordinates adapted to the propagation of null-like signals as observed by a geodesic observer. These "geodesic light-cone (GLC) coordinates" are general, adapted to…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-01 Fabien Nugier

The remarkable properties of the geodesic light-cone (GLC) coordinates allow analytic expressions for the light-cone observables, providing a new non-perturbative way for calculating the effects of inhomogeneities in our Universe. However,…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Fulvio Scaccabarozzi , Jaiyul Yoo

The remarkable properties of the recently proposed geodesic light-cone (GLC) gauge allow to explicitly solve the geodetic-deviation equation, and thus to derive an exact expression for the Jacobi map J^A_B(s,o) connecting a generic source s…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-13 G. Fanizza , M. Gasperini , G. Marozzi , G. Veneziano

We discuss the interpretation of the angles in the Geodesic Light-Cone (GLC) coordinates. In particular, we clarify the way in which these angles can be identified with the observed ones. We show that, although this identification is always…

General Relativity and Quantum Cosmology · Physics 2018-04-18 Ermis Mitsou , Fulvio Scaccabarozzi , Giuseppe Fanizza

We show that the angular directions locally measured by a static geodesic observer in a generic cosmological background and expressed in the system of Fermi Normal Coordinates always coincide with those expressed in the Geodesic-Light-Cone…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-08 Giuseppe Fanizza , Maurizio Gasperini , Giovanni Marozzi , Gabriele Veneziano

We present in this paper a new application of the geodesic light-cone (GLC) gauge for weak lensing calculations. Using interesting properties of this gauge, we derive an exact expression of the amplification matrix - involving convergence,…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-03 Giuseppe Fanizza , Fabien Nugier

Inspired by the fully non-linear Geodesic Light-Cone (GLC) gauge, we consider its analogous set of coordinates which describes the unperturbed Universe. Given this starting point, we then build a cosmological perturbation theory on top of…

General Relativity and Quantum Cosmology · Physics 2021-02-15 Giuseppe Fanizza , Giovanni Marozzi , Matheus Medeiros , Gloria Schiaffino

We present a new method to compute the deflection of light rays in a perturbed FLRW geometry. We exploit the properties of the Geodesic Light Cone (GLC) gauge where null rays propagate at constant angular coordinates irrespectively of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 G. Fanizza , M. Gasperini , G. Marozzi , G. Veneziano

Continuing work initiated in an earlier publication [Phys. Rev. D 69, 084007 (2004)], we construct a system of light-cone coordinates based at a geodesic world line of an arbitrary curved spacetime. The construction involves (i) an…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Brent Preston , Eric Poisson

If there is a null gradient field in 1+3 dimensional space-time, we can set up a kind of light-cone coordinate system in the space-time. In such coordinate system, the metric takes a simple form, which is much helpful for simplifying and…

General Physics · Physics 2017-12-08 Ying-Qiu Gu

The standard model of cosmology is based on the hypothesis that the Universe is spatially homogeneous and isotropic. When interpreting most observations, this cosmological principle is applied stricto sensu: the light emitted by distant…

General Relativity and Quantum Cosmology · Physics 2024-01-15 Pierre Fleury

This article proposes a comprehensive analysis of light propagation in an anisotropic and spatially homogeneous Bianchi I universe. After recalling that null geodesics are easily determined in such a spacetime, we derive the expressions of…

General Relativity and Quantum Cosmology · Physics 2015-03-12 Pierre Fleury , Cyril Pitrou , Jean-Philippe Uzan

An analysis of null geodesics in Schwarzschild de Sitter space is presented with special attention to their global `bending angles', local measurable angles, and the involvement of the cosmological constant. We make use of a general…

General Relativity and Quantum Cosmology · Physics 2016-09-19 Dmitri Lebedev , Kayll Lake

The aim of this work is the study of geodesics on Lorentzian homogeneous spaces of the form $M=G/\Lambda$, where $G$ is a solvable Lie group endowed with a bi-invariant Lorentzian metric and $\Lambda < G$ is a cocompact lattice. Conditions…

Differential Geometry · Mathematics 2024-11-22 Pablo Montenegro , Gabriela P. Ovando

We develop the spacetime approach to gravitational lensing by spherically symmetric perturbations of flat, cosmological constant-dominated Friedman-Robertson-Walker metrics. The geodesics of the spacetime are expressed as integral…

General Relativity and Quantum Cosmology · Physics 2025-08-19 Thomas P. Kling , Sophia MacQueen Pooler

Comparing the luminosity distance measurements to its theoretical predictions is one of the cornerstones in establishing the modern cosmology. However, as shown in Biern & Yoo, its theoretical predictions in literature are often plagued…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Jaiyul Yoo , Fulvio Scaccabarozzi

To understand the observational properties of cosmological models, in particular, the temperature of the cosmic microwave background radiation, it is necessary to study their null geodesics. Dynamical systems theory, in conjunction with the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Ulf S Nilsson , C. Uggla , J. Wainwright

The theory of gravitational lensing is reviewed from a spacetime perspective, without quasi-Newtonian approximations. More precisely, the review covers all aspects of gravitational lensing where light propagation is described in terms of…

General Relativity and Quantum Cosmology · Physics 2010-10-19 Volker Perlick

The modelling of light-like signals in General Relativity taking the form of impulsive gravitational waves and light-like shells of matter is examined. Systematic deductions from the Bianchi identities are made. These are based upon…

General Relativity and Quantum Cosmology · Physics 2009-10-31 C. Barrabès , P. A. Hogan

Gravitational Lensing is an efficient tool to probe: the mass distribution of collapsed systems: galaxies and clusters; high redshift objects thanks to the gravitational amplification; and the geometry of the Universe. I will review here…

Astrophysics · Physics 2007-05-23 J. -P. Kneib
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