Download or read book Constraining Dark Matter Physics with Cosmological Simulations written by Oliver D. Elbert and published by . This book was released on 2017 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark Matter (DM) accounts for the vast majority of mass in the universe, but the particle identity of dark matter remains a mystery. Uncovering the fundamental nature of DM remains one of the greatest challenges facing modern physics. Because the only information about DM comes from astrophysical observations, these are the best sources to constrain models. Dwarf galaxies present an especially tantalizing regime to investigate dark physics, as they have the highest ratio of dark to luminous matter and therefore will be most affected by differences between DM models. Additionally, this is precisely the scale where generic dark matter theories have the most difficulty reproducing astronomical observations, leading to the missing satellites, core-cusp and too-big-to-fail (TBTF) problems.A particular class of models with nuclear scale self-interactions (called SIDM) has emerged as a promising candidate. SIDM naturally forms cored halos, which may alleviate both the core-cusp and TBTF problems. However, at larger scales the the interplay between SIDM halos and the galaxies residing in them is poorly understood, complicating this picture greatly. In this thesis I present numerical simulations of SIDM and CDM halos investigating these issues. I show that at dwarf scales SIDM cross sections as small as 0.5cm2 g--1 solve the TBTF and core-cusp problems, and that cross sections 2 orders of magnitude larger are not ruled out. I have also embedded gravitational potentials that approximate realistic galaxies in simulations of larger haloes in order to test the impact of galaxy formation on SIDM halos. These simulations show that SIDM is indistinguishable from CDM in systems where the galaxy dominates the central region, but in galaxies with higher mass-to-light ratios or less centrally concentrated baryons it is possible to constrain SIDM cross sections. In the galaxy cluster regime I show that an SIDM cross section of $0.1-0.2 cm2 g --1 is preferred to CDM or other SIDM cross sections.
Download or read book Illuminating Dark Matter written by Rouven Essig and published by Springer Nature. This book was released on 2019-11-22 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on a Simons Symposium held in 2018, the proceedings in this volume focus on the theoretical, numerical, and observational quest for dark matter in the universe. Present ground-based and satellite searches have so far severely constrained the long-proposed theoretical models for dark matter. Nevertheless, there is continuously growing astrophysical and cosmological evidence for its existence. To address present and future developments in the field, novel ideas, theories, and approaches are called for. The symposium gathered together a new generation of experts pursuing innovative, more complex theories of dark matter than previously considered.This is being done hand in hand with experts in numerical astrophysical simulations and observational techniques—all paramount for deciphering the nature of dark matter. The proceedings volume provides coverage of the most advanced stage of understanding dark matter in various new frameworks. The collection will be useful for graduate students, postdocs, and investigators interested in cutting-edge research on one of the biggest mysteries of our universe.
Download or read book Dark Matter and Dark Energy written by Sabino Matarrese and published by Springer Science & Business Media. This book was released on 2011-02-10 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book brings together reviews from leading international authorities on the developments in the study of dark matter and dark energy, as seen from both their cosmological and particle physics side. Studying the physical and astrophysical properties of the dark components of our Universe is a crucial step towards the ultimate goal of unveiling their nature. The work developed from a doctoral school sponsored by the Italian Society of General Relativity and Gravitation. The book starts with a concise introduction to the standard cosmological model, as well as with a presentation of the theory of linear perturbations around a homogeneous and isotropic background. It covers the particle physics and cosmological aspects of dark matter and (dynamical) dark energy, including a discussion of how modified theories of gravity could provide a possible candidate for dark energy. A detailed presentation is also given of the possible ways of testing the theory in terms of cosmic microwave background, galaxy redshift surveys and weak gravitational lensing observations. Included is a chapter reviewing extensively the direct and indirect methods of detection of the hypothetical dark matter particles. Also included is a self-contained introduction to the techniques and most important results of numerical (e.g. N-body) simulations in cosmology. " This volume will be useful to researchers, PhD and graduate students in Astrophysics, Cosmology Physics and Mathematics, who are interested in cosmology, dark matter and dark energy.
Download or read book Probing Cosmic Dark Matter and Dark Energy with Weak Gravitational Lensing Statistics written by Masato Shirasaki and published by Springer. This book was released on 2015-11-18 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book the applicability and the utility of two statistical approaches for understanding dark energy and dark matter with gravitational lensing measurement are introduced. For cosmological constraints on the nature of dark energy, morphological statistics called Minkowski functionals (MFs) to extract the non-Gaussian information of gravitational lensing are studied. Measuring lensing MFs from the Canada–France–Hawaii Telescope Lensing survey (CFHTLenS), the author clearly shows that MFs can be powerful statistics beyond the conventional approach with the two-point correlation function. Combined with the two-point correlation function, MFs can constrain the equation of state of dark energy with a precision level of approximately 3–4 % in upcoming surveys with sky coverage of 20,000 square degrees. On the topic of dark matter, the author studied the cross-correlation of gravitational lensing and the extragalactic gamma-ray background (EGB). Dark matter annihilation is among the potential contributors to the EGB. The cross-correlation is a powerful probe of signatures of dark matter annihilation, because both cosmic shear and gamma-ray emission originate directly from the same dark matter distribution in the universe. The first measurement of the cross-correlation using a real data set obtained from CFHTLenS and the Fermi Large Area Telescope was performed. Comparing the result with theoretical predictions, an independent constraint was placed on dark matter annihilation. Future lensing surveys will be useful to constrain on the canonical value of annihilation cross section for a wide range of mass of dark matter annihilation. Future lensing surveys will be useful to constrain on the canonical value of annihilation cross section for a wide range of mass of dark matter.
Download or read book From Cosmological Simulations to Dark Matter Detection written by Luis Arturo Nunez de Villavicencio Castine and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This interdisciplinary thesis addresses spiral galaxy formation and dark matter phenomenology as well as its detection by the ANTARES neutrino telescope. A suite of high-resolution cosmological hydrodynamics simulations, with theadaptive mesh refinement code RAMSES, of the same galaxy, is performed using different modellings of stellar formation (Kennicut law (KS) versus gravo-turbulent criteria (multiFF)) and supernovae feed back (delayed cooling (DC) versus mechanical feedback (ME)). The results on the morphology and the properties of the galaxies are compared to observational constraints and high light the impact of baryonic physics on a spiral galaxy. The most elaborated scenarios (multi FF+DC or multi FF+ME) are clearly favoured and give rise to more realistic stellar mass and disc morphology.The resulting dark matter distributions in halos are also analyzed and compared showing some significant differences. The understanding of baryonic physics is crucial to understand the dark matter distribution. Namely, it is specifically modified and contracted by the baryonic potential of each simulation with a determining impact on direct and indirect dark matter detection. Moreover,we also use those informations about the dark matter to probe the Eddington inversion method aiming at predicting phase-space distribution from the gravitationnal potential. Those results are positive and very consistent and promisingin view of GAIA data analysis improvement and calibration. Further more, we also revisit the astrophysical uncertainties related to the dark matter velocity distribution relevant in the capture by the Sun and evaluate those effects to about 15-20% on the capture rate.
Download or read book Dark Matter in Astro and Particle Physics written by Hans-Volker Klapdor-Kleingrothaus and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fourth HEIDELBERG International Conference on Dark Matter in Astro and Particle Physics, DARK2002, was held in Cape Town, South Africa, in the period 4-9 February 2002. This majestic natural area was the site of the first conference of this series (hosted since 1996 in Heidelberg) to be held outside of Germany. Dark Matter has become one of the most exciting and central fields of as trophysics, particle physics and cosmology. The conference covered, as usual for this series, a large range of topics, theoretical and experimental. Topics included Astronomical Evidence for Dark Matter, the Cosmic Microwave Background, Supersymmetry, Inflation and Dark Energy, Structure Formation, Hot and Cold Dark Matter, and Ultrahigh Energy Cosmic Rays all of which were represented by experts in the field. It was very nice to see again many of our 'old' friends in Dark Matter here in South Africa. The organizers were very glad to see, in addition to world experts, the new generation here. Many young participants gave very nice professional talks during the conference. We are grateful to John Ellis for doing an incredible job preparing his excellent summary talk during the sessions. Some special interest and intensive discussions were naturally raised by the first announcement of terrestrial evidence for hot dark matter, obtained from neutrino less double beta decay. This now adds to the evidence for cold dark matter which we have from DAM A for several years already, and which remained unchallenged up to now by other experiments.
Download or read book Particle Dark Matter written by Gianfranco Bertone and published by Cambridge University Press. This book was released on 2010-01-07 with total page 763 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the dark matter problem in particle physics, astrophysics and cosmology for graduate students and researchers.
Download or read book Simulations of Dark Energy Cosmologies written by Elise Jennings and published by Springer Science & Business Media. This book was released on 2012-05-27 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major outstanding problem in physics is understanding the nature of the dark energy that is driving the accelerating expansion of the Universe. This thesis makes a significant contribution by demonstrating, for the first time, using state-of-the-art computer simulations, that the interpretation of future galaxy survey measurements is far more subtle than is widely assumed, and that a major revision to our models of these effects is urgently needed. The work contained in the thesis was used by the WiggleZ dark energy survey to measure the growth rate of cosmic structure in 2011 and had a direct impact on the design of the surveys to be conducted by the European Space Agency's Euclid mission, a 650 million euro project to measure dark energy.
Download or read book Beyond CDM written by Sownak Bose and published by Springer. This book was released on 2018-08-02 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book employs computer simulations of ‘artificial’ Universes to investigate the properties of two popular alternatives to the standard candidates for dark matter (DM) and dark energy (DE). It confronts the predictions of theoretical models with observations using a sophisticated semi-analytic model of galaxy formation. Understanding the nature of dark matter (DM) and dark energy (DE) are two of the most central problems in modern cosmology. While their important role in the evolution of the Universe has been well established—namely, that DM serves as the building blocks of galaxies, and that DE accelerates the expansion of the Universe—their true nature remains elusive. In the first half, the authors consider ‘sterile neutrino’ DM, motivated by recent claims that these particles may have finally been detected. Using sophisticated models of galaxy formation, the authors find that future observations of the high redshift Universe and faint dwarf galaxies in the Local Group can place strong constraints on the sterile neutrino scenario. In the second half, the authors propose and test novel numerical algorithms for simulating Universes with a ‘modified’ theory of gravity, as an alternative explanation to accelerated expansion. The authors’ techniques improve the efficiency of these simulations by more than a factor of 20 compared to previous methods, inviting the readers into a new era for precision cosmological tests of gravity.
Download or read book Cosmological Physics written by J. A. Peacock and published by Cambridge University Press. This book was released on 1999 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive and authoritative introduction to contemporary cosmology for advanced undergraduate and graduate students.
Download or read book Self interacting Dark Matter in Cosmological Simulations written by Alexander Bastidas Fry and published by . This book was released on 2015 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-Interacting Dark Matter is a cosmologically consistent alternative theory to Cold Dark Matter that solves problems of the Cold Dark Matter model on small scales. Our N-body simulations demonstrate that Self-Interacting Dark Matter creates constant density cores that are consistent with observations of Local Group dwarf galaxies. However, the apparent problems of Cold Dark Matter have natural astrophysical contributions from baryonic supernovae feedback. The evidence for Self-Interacting Dark Matter taken together with the evidence for the need for better feedback models presents a challenging environment in which to place constraints on either. We use high resolution cosmological simulations to compare the detailed properties of galaxies at a range of masses with a focus on dwarf galaxies which are the most dark matter dominated galaxies in the universe. We conclude that it is possible that velocity dependent Self-Interacting Dark Matter could explain the common mass scale of dark matter on small scales, the too big to fail problem, and the core versus cusp problem even in the absence of strong stellar feedback; however, baryonic processes offer solutions to these same problems. We find that once baryon physics and outflows are introduced, cores are created in both Self-Interacting Dark Matter and Cold Dark Matter cosmologies.
Download or read book Merging Processes in Galaxy Clusters written by L. Feretti and published by Springer Science & Business Media. This book was released on 2006-04-18 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mergers are the mechanisms by which galaxy clusters are assembled through the hierarchical growth of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Many of the observed properties of clusters depend on the physics of the merging process. These include substructure, shock, intra cluster plasma temperature and entropy structure, mixing of heavy elements within the intra cluster medium, acceleration of high-energy particles, formation of radio halos and the effects on the galaxy radio emission. This book reviews our current understanding of cluster merging from an observational and theoretical perspective, and is appropriate for both graduate students and researchers in the field.
Download or read book Sources and Detection of Dark Matter and Dark Energy in the Universe written by David B. Cline and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark matter research is one of the most fascinating and active fields among current high-profile scientific endeavours. It holds the key to all major breakthroughs to come in the fields of cosmology and astroparticle physics. The present volume is particularly concerned with the sources and the detection of dark matter and dark energy in the universe and will prove to be an invaluable research tool for all scientists who work in this field.
Download or read book Progress in Dark Matter Research written by J. Val Blain and published by Nova Publishers. This book was released on 2005 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is generally believed that most of the matter in the universe is dark, i.e. cannot be detected from the light which it emits (or fails to emit). Its presence is inferred indirectly from the motions of astronomical objects, specifically stellar, galactic, and galaxy cluster/supercluster observations. It is also required in order to enable gravity to amplify the small fluctuations in the cosmic microwave background enough to form the large-scale structures that we see in the universe today. For each of the stellar, galactic, and galaxy cluster/supercluster observations the basic principle is that if we measure velocities in some region, then there has to be enough mass there for gravity to stop all the objects flying apart. Dark matter has important consequences for the evolution of the Universe and the structure within it. According to general relativity, the Universe must conform to one of three possible types: open, flat, or closed. The total amount of mass and energy in the universe determines which of the three possibilities applies to the Universe. In the case of an open Universe, the total mass and energy density (denoted by the Greek letter Omega) is less than unity. If the Universe is closed, Omega is greater than unity. For the case where Omega is exactly equal to one the Universe is "flat". This book details leading-edge research from around the globe.
Download or read book Dark Matter And Cosmic Web Story written by Jaan Einasto and published by World Scientific. This book was released on 2013-11-05 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concepts of dark matter and the cosmic web are some of the most significant developments in cosmology in the past century. They have decisively changed the classical cosmological paradigm, which was first elaborated upon during the first half of the 20th century but ran into serious problems in the second half. Today, they are integral parts of modern cosmology, which explains everything from the Big Bang to inflation to the large scale structure of the Universe.Dark Matter and Cosmic Web Story describes the contributions that led to a paradigm shift from the Eastern point of view. It describes the problems with the classical view, the attempts to solve them, the difficulties encountered by those solutions, and the conferences where the merits of the new concepts were debated. Amidst the science, the story of scientific work in a small country occupied by the Soviet Union and the tumultuous events that led to its breakup are detailed as well.This book is accompanied by a website which contains additional material: copies of the originals of some crucial papers, astronomical movies, and movies which showcase the private life of the author.
Download or read book Dark Matter And Cosmic Web Story Second Edition written by Jaan Einasto and published by World Scientific. This book was released on 2024-04-29 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concepts of dark matter and the cosmic web are some of the most significant developments in cosmology in the past century. They have decisively changed the classical cosmological paradigm, which was first elaborated upon during the first half of the 20th century but ran into serious problems in the second half. Today, they are integral parts of modern cosmology, which explains everything from the Big Bang to inflation to the large-scale structure of the Universe.Dark Matter and Cosmic Web Story describes the contributions that led to a paradigm shift from the Eastern point of view. It describes the problems with the classical view, the attempts to solve them, the difficulties encountered by those solutions, and the conferences where the merits of the new concepts were debated. Amidst the science, the story of scientific work in a small country occupied by the Soviet Union and the tumultuous events that led to its breakup are detailed as well.The development of cosmology has often treated as a West-East conflict between the American school led by Jim Peebles in Princeton and the Soviet team led by Yakov Zeldovich in Moscow. Actually, the development of ideas was broader, and a certain role played the Tartu team. The Tartu cosmology school was founded by Ernst Öpik and has its own traditions and attitude to science. In the new edition of the book the interplay between three cosmology schools is written in more detail. The recent development of dark matter and cosmic web studies is described, as well as the evolution of global properties of the cosmic web.This book is accompanied by a website which contains additional material: copies of the originals of some crucial papers, astronomical movies, and movies which showcase the private life of the author. In this second edition, two chapters on the statistical description of the cosmic web and its development were added, as well as chapter on the sociology of science. To keep the length of this book reasonable, a lot of reorganisation of the text has been done as well.
Download or read book Modern Cosmology written by Scott Dodelson and published by Academic Press. This book was released on 2003-03-13 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: An advanced text for senior undergraduates, graduate students and physical scientists in fields outside cosmology. This is a self-contained book focusing on the linear theory of the evolution of density perturbations in the universe, and the anisotropiesin the cosmic microwave background.
