Advanced Statistical Methods for Astrophysical Probes of Cosmology

Advanced Statistical Methods for Astrophysical Probes of Cosmology

Author: Marisa Cristina March

Publisher: Springer Science & Business Media

ISBN: 9783642350603

Category: Science

Page: 180

View: 727

This thesis explores advanced Bayesian statistical methods for extracting key information for cosmological model selection, parameter inference and forecasting from astrophysical observations. Bayesian model selection provides a measure of how good models in a set are relative to each other - but what if the best model is missing and not included in the set? Bayesian Doubt is an approach which addresses this problem and seeks to deliver an absolute rather than a relative measure of how good a model is. Supernovae type Ia were the first astrophysical observations to indicate the late time acceleration of the Universe - this work presents a detailed Bayesian Hierarchical Model to infer the cosmological parameters (in particular dark energy) from observations of these supernovae type Ia.

Advanced Statistical Methods for Astrophysical Probes of Cosmology

Advanced Statistical Methods for Astrophysical Probes of Cosmology

Author: Marisa Cristina March

Publisher: Springer

ISBN: 3642444547

Category: Science

Page: 180

View: 142

This thesis explores advanced Bayesian statistical methods for extracting key information for cosmological model selection, parameter inference and forecasting from astrophysical observations. Bayesian model selection provides a measure of how good models in a set are relative to each other - but what if the best model is missing and not included in the set? Bayesian Doubt is an approach which addresses this problem and seeks to deliver an absolute rather than a relative measure of how good a model is. Supernovae type Ia were the first astrophysical observations to indicate the late time acceleration of the Universe - this work presents a detailed Bayesian Hierarchical Model to infer the cosmological parameters (in particular dark energy) from observations of these supernovae type Ia.

Astrostatistical Challenges for the New Astronomy

Astrostatistical Challenges for the New Astronomy

Author: Joseph M. Hilbe

Publisher: Springer Science & Business Media

ISBN: 9781461435082

Category: Mathematics

Page: 238

View: 429

Astrostatistical Challenges for the New Astronomy presents a collection of monographs authored by several of the disciplines leading astrostatisticians, i.e. by researchers from the fields of statistics and astronomy-astrophysics, who work in the statistical analysis of astronomical and cosmological data. Eight of the ten monographs are enhancements of presentations given by the authors as invited or special topics in astrostatistics papers at the ISI World Statistics Congress (2011, Dublin, Ireland). The opening chapter, by the editor, was adapted from an invited seminar given at Los Alamos National Laboratory (2011) on the history and current state of the discipline; the second chapter by Thomas Loredo was adapted from his invited presentation at the Statistical Challenges in Modern Astronomy V conference (2011, Pennsylvania State University), presenting insights regarding frequentist and Bayesian methods of estimation in astrostatistical analysis. The remaining monographs are research papers discussing various topics in astrostatistics. The monographs provide the reader with an excellent overview of the current state astrostatistical research, and offer guidelines as to subjects of future research. Lead authors for each chapter respectively include Joseph M. Hilbe (Jet Propulsion Laboratory and Arizona State Univ); Thomas J. Loredo (Dept of Astronomy, Cornell Univ); Stefano Andreon (INAF-Osservatorio Astronomico di Brera, Italy); Martin Kunz ( Institute for Theoretical Physics, Univ of Geneva, Switz); Benjamin Wandel ( Institut d'Astrophysique de Paris, Univ Pierre et Marie Curie, France); Roberto Trotta (Astrophysics Group, Dept of Physics, Imperial College London, UK); Phillip Gregory (Dept of Astronomy, Univ of British Columbia, Canada); Marc Henrion (Dept of Mathematics, Imperial College, London, UK); Asis Kumar Chattopadhyay (Dept of Statistics, Univ of Calcutta, India); Marisa March (Astrophysics Group, Dept of Physics, Imperial College, London, UK)./body

Cosmology with Clusters of Galaxies

Cosmology with Clusters of Galaxies

Author: Sandor Mihaly Molnar

Publisher: Nova Science Pub Incorporated

ISBN: 1634821076

Category: Science

Page: 190

View: 411

This book presents a comprehensive review of the methods applied to derive cosmological parameters for a given model and test different cosmological models using the most massive collapsed structures in our Universe: clusters of galaxies. Clusters typically consist of hundreds of galaxies and high-temperature ionised gas trapped in their gravitational field dominated by dark matter extending out to 2-3 Mpc. The formation, evolution, and structure of these massive rare objects are sensitive probes of the assumed cosmology. This is a multidisciplinary field of astrophysics involving multi-wavelength observations, gravity theory, atomic physics, plasma physics, magneto-hydrodynamics, astrophysical cosmology and numerical simulations. Our understanding of the physics of clusters, which is essential when using them for cosmology, has been improved tremendously due to the recent advent of technology and observational strategy in multi-frequency observations, and enhanced by improved numerical simulations made possible by more advanced high performance computers. As a result of these developments, cosmology with clusters of galaxies has become a mature discipline recently, and provided an important contribution to establish our concordance cosmological constant dominated cold dark matter model. In the near future we expect a rapid expansion of this field due to results from new cluster surveys and multi-wavelength observations. This timely volume on this exciting newly established field discusses galaxy cluster physics and provides a detailed description of using clusters to derive cosmological parameters applying accurate measurements of individual clusters as well as using clusters as a statistical tool. A detailed discussion is given on degeneracies between derived parameters and the systematic effects, which are becoming a limiting factor. An account for using clusters to test different cosmological models is also presented. This volume provides an introduction to galaxy cluster cosmology for physics and astronomy graduate students and serves as a reference source for professionals.

The Deep Universe

The Deep Universe

Author: A.R. Sandage

Publisher: Springer Science & Business Media

ISBN: 9783540316350

Category: Science

Page: 526

View: 419

Written by three celebrated astronomers renowned for their excellence in both research and teaching, the central theme is approached in three complementary ways: the smooth evolution of the universe from the Big Bang to the present structures of matter; as a meandering road paved by our observations of stars, galaxies, and clusters; and how these approaches have been gradually developed and intertwined in the historical process leading to modern-day cosmology.

Plasmas in the Universe

Plasmas in the Universe

Author: Società italiana di fisica

Publisher: IOS Press

ISBN: 1586030736

Category: Science

Page: 556

View: 790

This book illustrates new developments in the fields of space and solar physics, stellar physics, extragalactic physics and cosmology. It also elaborates upon the progress of laboratory plasma physics. One of the topics discussed is the existence of collective processes, both linear and non-linear, that can explain key elements of accretion physics, magnetic reconnection, the formation of 'strange' particle distributions, particle scattering phenomena, etc. Astrophysical plasma are dominated by turbulent or quasi-turbulent processes which interactively associate instabilities, radiation processes and plasma-wave scattering. The resulting scenario, which is outside thermodynamics and conventional statistical physics, is too difficult to describe theoretically, but today there are large-scale experiments and powerful computational tools allowing for the exploration of an almost similarly complex variety of phenomena. Several contributions to this book present indications of the influence of nonlinear phenomena in astrophysical applications. This work marks the fast growth of plasma astrophysics thanks to new observations in the high energy band of the spectrum on the one hand and the possibility of validating and bringing to light relevant new theories by increasingly sophisticated machines on the other.

Bulletin of the Atomic Scientists

Bulletin of the Atomic Scientists

Author:

Publisher:

ISBN:

Category:

Page: 88

View: 343

The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.