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Related papers: How many cosmological parameters?

200 papers

We examine the constraints that satellite-acquired Type Ia and IIP supernova apparent magnitude versus redshift data will place on cosmological model parameters in models with and without a constant or time-variable cosmological constant…

Astrophysics · Physics 2009-10-31 Silviu Podariu , Peter Nugent , Bharat Ratra

Several recent papers have made claims about the detection of an asymmetric distribution of large scale power in the cosmic microwave background anisotropy as measured by the WMAP satellite. In this paper, we investigate how the estimates…

Astrophysics · Physics 2009-11-10 F. K. Hansen , A. Balbi , A. J. Banday , K. M. Gorski

When combining data sets to perform parameter inference, the results will be unreliable if there are unknown systematics in data or models. Here we introduce a flexible methodology, BACCUS: BAyesian Conservative Constraints and Unknown…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 José Luis Bernal , John A. Peacock

We define an optimal basis system into which cosmological observables can be decomposed. The basis system can be optimised for a specific cosmological model or for an ensemble of models, even if based on drastically different physical…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-21 M. Maturi , C. Mignone

We provide a fast algorithm to diagnose any directional dependence in the cosmological parameters by calculating maps of local cosmological parameter estimates and their joint errors. The technique implements a fast quadratic estimator…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-26 Suvodip Mukherjee , Benjamin D. Wandelt

We introduce a dynamical model to reduce a large cosmological constant to a sufficiently small value. The basic ingredient in this model is a distinction which has been made between the two unit systems used in cosmology and particle…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Yousef Bisabr

A mathematical model of the Universe evolution, based on asymmetric doublet of classical and phantom dcalar Higgs fields with a kinetic connection between the components, has been constructed and studied. A detailed qualitative analysis was…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Yu. G. Ignat'ev , I. A. Kokh

We are at a specific period of modern cosmology, during which the large increase of the amount of data leads to the idea that the determination of cosmological parameters has been achieved with a rather good precision. There is a large…

Astrophysics · Physics 2017-08-23 A. Blanchard

Using three parametrizations of the gamma ray burst count data comparison is made to cosmological source models. While simple models can fit <V/Vmax> and faint end slope constraints, the addition of a logarithmic count range variable…

Astrophysics · Physics 2007-05-23 Eric V. Linder

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

We introduce the notion of the cosmic numbers of a cosmological model, and discuss how they can be used to naturally classify models according to their ability to solve some of the problems of the standard cosmological model.

Astrophysics · Physics 2009-11-07 P. P. Avelino , C. J. A. P. Martins

A nontrivial topology of the spatial section of the universe is an observable, which can be probed for all locally homogeneous and isotropic universes, without any assumption on the cosmological density parameters. We discuss how one can…

Astrophysics · Physics 2008-11-26 M. J. Reboucas

A theory of the cosmological constant Lambda is currently out of reach. Still, one can start from a set of axioms that describe the most desirable properties a cosmological constant should have. This can be seen in certain analogy to the…

General Relativity and Quantum Cosmology · Physics 2009-06-23 Christian Beck

Cosmology has come a long way from being based on a small number of observations to being a data-driven precision science. We discuss the questions "What is observable?", "What in the Universe is knowable?" and "What are the fundamental…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-28 Florent Leclercq , Alice Pisani , Benjamin D. Wandelt

We introduce "anamorphic" cosmology, an approach for explaining the smoothness and flatness of the universe on large scales and the generation of a nearly scale-invariant spectrum of adiabatic density perturbations. The defining feature is…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-02 Anna Ijjas , Paul J. Steinhardt

In cosmology many dramatically different scenarios with the past (big bang versus bounce) and in the future (de Sitter versus big rip) singularities are compatible with the present day observations. This difficulty is called the degeneracy…

Astrophysics · Physics 2009-11-13 Wlodzimierz Godlowski Marek Szydlowski

In this paper, we study the degeneracies among several cosmological parameters in detail and discuss their impacts on the determinations of these parameters from the current and future observations. By combining the latest data sets,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Hong Li , Jun-Qing Xia

Current and upcoming cosmological surveys will produce unprecedented amounts of high-dimensional data, which require complex high-fidelity forward simulations to accurately model both physical processes and systematic effects which describe…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-11 Aizhan Akhmetzhanova , Carolina Cuesta-Lazaro , Siddharth Mishra-Sharma

The Planck satellite is expected to improve the measurement of most cosmological parameters by several factors with respect to current WMAP results. The actual performance may depend upon various aspects of the data analysis. In this paper…

Astrophysics · Physics 2010-11-02 L. P. L. Colombo , E. Pierpaoli , J. R. Pritchard

Most cosmological parameter estimations are based on the same set of observations and are therefore not independent. Here, we test the consistency of parameter estimations using a combination of large-scale structure and supernovae data,…

Astrophysics · Physics 2009-11-10 Carolina Odman , Mike Hobson , Anthony Lasenby , Alessandro Melchiorri