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In this paper, we present a novel approach to accelerate the Bayesian inference process, focusing specifically on the nested sampling algorithms. Bayesian inference plays a crucial role in cosmological parameter estimation, providing a…

Instrumentation and Methods for Astrophysics · Physics 2024-10-17 Isidro Gómez-Vargas , J. Alberto Vázquez

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

We have fossil evidence from the thermal background radiation that our universe expanded from a considerably hotter denser state. We have a well defined and testable description of the expansion, the relativistic Friedmann-Lemaitre model.…

Astrophysics · Physics 2009-10-31 P. J. E. Peebles

A generalized quintessence model is presented which corresponds to a richer vacuum structure that, besides a time-dependent, slowly varying scalar field, contains a varying cosmological term. From first principles we determine a number of…

Astrophysics · Physics 2009-10-31 Pedro F. Gonzalez-Diaz

The classical Bayesian posterior arises naturally as the unique solution of several different optimization problems, without the necessity of interpreting data as conditional probabilities and then using Bayes' Theorem. For example, the…

Statistics Theory · Mathematics 2012-03-02 Theodore P. Hill , Marco Dall'Aglio

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are used to set…

Astrophysics · Physics 2007-05-23 Ofer Lahav

Many synoptic surveys are observing large parts of the sky multiple times. The resulting lightcurves provide a wonderful window to the dynamic nature of the universe. However, there are many significant challenges in analyzing these light…

Applications · Statistics 2016-02-04 Julian Faraway , Ashish Mahabal , Jiayang Sun , Xiaofeng Wang , Yi , Wang , Lingsong Zhang

The well-known Bayes theorem assumes that a posterior distribution is a probability distribution. However, the posterior distribution may no longer be a probability distribution if an improper prior distribution (non-probability measure)…

Instrumentation and Methods for Astrophysics · Physics 2018-08-28 Hyungsuk Tak , Sujit K. Ghosh , Justin A. Ellis

Accurate analyses of present and next-generation galaxy surveys require new ways to handle effects of non-linear gravitational structure formation in data. To address these needs we present an extension of our previously developed algorithm…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Jens Jasche , Guilhem Lavaux

In the context of cosmography approach and using the data of Hubble diagram for supernovae, quasars and gamma-ray bursts, we study some DE parametrizations and also the concordance $\Lambda$CDM universe. Using the different combinations of…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-09 Mehdi Rezaei , Saeed Pour Ojaghi , Mohammad Malekjani

We present a Bayesian reconstruction method which maps a galaxy distribution from redshift-space to real-space inferring the distances of the individual galaxies. The method is based on sampling density fields assuming a lognormal prior…

FRW models of the universe have been studied in the cosmological theory based on Lyra's manifold. A new class of exact solutions has been obtained by considering a time dependent displacement field for variable deceleration parameter from…

General Relativity and Quantum Cosmology · Physics 2015-06-25 A. Pradhan , J. P. Shahi , C. B. Singh

Nowadays, g-mode detection is based upon a priori theoretical knowledge. By doing so, detection becomes more restricted to what we can imagine. De facto, the universe of possibilities is made narrower. Such an approach is pertinent for…

Astrophysics · Physics 2009-11-13 T. Appourchaux

The classical stochastic model of cosmology recently developed by us is reconsidered. In that approach the parameter $w$ defined by the equation of state $p=w{\rho}$ was taken to be fluctuating with mean zero and we compared the theoretical…

Astrophysics · Physics 2009-11-07 Moncy V. John , C. Sivakumar , K. Babu Joseph

Comparing competing mathematical models of complex natural processes is a shared goal among many branches of science. The Bayesian probabilistic framework offers a principled way to perform model comparison and extract useful metrics for…

We present a Bayesian hierarchical framework for a principled data analysis pipeline of peculiar velocity surveys, which makes explicit the inference problem of constraining cosmological parameters from redshift-independent distance…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-24 Lawrence Dam

We present methods to rigorously extract parameter combinations that are constrained by data from posterior distributions. The standard approach uses linear methods that apply to Gaussian distributions. We show the limitations of the linear…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Tara Dacunha , Marco Raveri , Minsu Park , Cyrille Doux , Bhuvnesh Jain

We argue that standard tools of holography can be used to describe fully non-perturbative microscopic models of cosmology in which a period of accelerated expansion may result from the positive potential energy of time-dependent scalar…

High Energy Physics - Theory · Physics 2022-03-23 Stefano Antonini , Petar Simidzija , Brian Swingle , Mark Van Raamsdonk

Extracting accurate cosmological information from galaxy-galaxy and galaxy-matter correlation functions on non-linear scales ($\lesssim 10 h^{-1} \mathrm{Mpc}$) requires cosmological simulations. Additionally, one has to marginalise over…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Johannes U. Lange , Frank C. van den Bosch , Andrew R. Zentner , Kuan Wang , Andrew P. Hearin , Hong Guo

Exoplanet research is carried out at the limits of the capabilities of current telescopes and instruments. The studied signals are weak, and often embedded in complex systematics from instrumental, telluric, and astrophysical sources.…

Instrumentation and Methods for Astrophysics · Physics 2019-02-06 Hannu Parviainen
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