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The next decade of survey astronomy has the potential to transform our knowledge of variable stars. Stellar variability underpins our knowledge of the cosmological distance ladder, and provides direct tests of stellar formation and…

Using a new sub-sample of observed strong gravitational lens systems, for the first time, we present the equation for the angular diameter distance in the $y$-redshift scenario for cosmography and use it to test the cosmographic parameters.…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 Andrés Lizardo , Mario H. Amante , Miguel A. García-Aspeitia , Juan Magaña , V. Motta

This is the dawning of the age of precision cosmology, when all the important parameters will be established to one significant figure or better, within the cosmological model. In the age of accurate cosmology the model, which nowadays…

Astrophysics · Physics 2007-05-23 P. J. E. Peebles

We present here the transformations required to recast the Robertson-Walker metric and Friedmann-Robertson-Walker equations in terms of observer-dependent coordinates for several commonly assumed cosmologies. The overriding motivation is…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia , Majd Abdelqader

We point out that polarization measurements as planned for the upcoming PLANCK mission can significantly enhance the accuracy of cosmic parameter estimation compared to the temperature anisotropy spectrum alone. In order to illustrate this,…

Astrophysics · Physics 2007-05-23 Pavel Naselsky , Jens Schmalzing , Jesper Sommer-Larsen , Steen Hannested

Measurements of the cosmic microwave background (CMB) radiation provide a unique opportunity for a direct study of the primordial cosmic plasma at redshift z ~1000. The angular power spectra of temperature and polarisation fluctuations are…

Astrophysics · Physics 2009-11-10 Marco Bersanelli , Davide Maino , Aniello Mennella

Galaxy redshift surveys are a major tool to address the most challenging cosmological problems facing cosmology, like the nature of dark energy and properties dark matter. The same observations are useful for a much larger variety of…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Laerte Sodre

Since the late 1970's, redshift surveys have been vital for progress in understanding large-scale structure in the Universe. The original CfA redshift survey collected spectra of 20-30 galaxies per clear night on a 1.5 meter telescope; over…

Astrophysics · Physics 2009-11-06 Marc Davis , Jeffrey Newman

The redshift of light is calculated for an anisotropic cosmological spacetime. Two different approaches are considered. In the first one, electromagnetic waves are modeled using the geometrical optics (high--frequency) approximation. This…

General Relativity and Quantum Cosmology · Physics 2018-05-10 Sergio A. Hojman , Felipe A. Asenjo

The ability to map the cosmological expansion has developed enormously, spurred by the turning point one decade ago of the discovery of cosmic acceleration. The standard model of cosmology has shifted from a matter dominated, standard…

Astrophysics · Physics 2009-06-23 Eric V. Linder

An emerging theme in modern astrophysics is the connection between astronomical observations and the underlying physical phenomena that drive our cosmos. Both the mechanisms responsible for the observed astrophysical phenomena and the tools…

Future surveys of large-scale structure will be able to measure perturbations on the scale of the cosmological horizon, and so could potentially probe a number of novel relativistic effects that are negligibly small on sub-horizon scales.…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-08 David Alonso , Philip Bull , Pedro G. Ferreira , Roy Maartens , Mario G. Santos

The next generation of telescopes will usher in an era of precision cosmology, capable of determining the cosmological model to beyond the percent level. For this to be effective, the theoretical model must be understood to at least the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Obinna Umeh , Chris Clarkson , Roy Maartens

We extract constraints on the transition redshift $z_{tr}$, determining the onset of cosmic acceleration, predicted by an effective cosmographic construction, in the framework of $f(T)$ gravity. In particular, employing cosmography we…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Salvatore Capozziello , Orlando Luongo , Emmanuel N. Saridakis

The specific astrophysical data collected during the last decade causes the need for the modification of the expression for the Einstein-Hilbert action, and several attempts sufficing this need are known. The modification suggested in this…

General Relativity and Quantum Cosmology · Physics 2012-07-04 Sergey Siparov , Nicoleta Brinzei

The observed two-point correlation functions of galaxies in redshift space become anisotropic due to the geometry of the universe as well as due to the presence of the peculiar velocity field. On the basis of linear perturbation theory, we…

Astrophysics · Physics 2009-10-30 Takahiro T. Nakamura , Takahiko Matsubara , Yasushi Suto

The large-scale structure of the Universe is a rich source of information to test the consistency of General Relativity on cosmological scales. We briefly describe how the observed distributions of galaxies is affected by redshift-space…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-17 Daniel Sobral-Blanco

Despite the observational success of the standard model of cosmology, present-day observations do not tightly constrain the nature of dark matter and dark energy and modifications to the theory of general relativity. Here, we will discuss…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-10 Valerio Marra , Rogerio Rosenfeld , Riccardo Sturani

Wavelets have been used extensively for several years now in astronomy for many purposes, ranging from data filtering and deconvolution, to star and galaxy detection or cosmic ray removal. More recent sparse representations such ridgelets…

Instrumentation and Methods for Astrophysics · Physics 2009-03-20 Jean-Luc Starck , Jerome Bobin

The Cosmological Principle posits that the Universe is isotropic on the largest scales. While widely supported, this foundational assumption remains testable. We analyse the angular distribution of over one million quasars from the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-04 Amit Mondal , Biswajit Pandey , Krishna Ghosh
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