In this thesis, we calculate current constraints on dark energy and study how tooptimally use the cosmological tools at our disposal to learn about its nature. With these papers, einstein provided the framework for understanding modern astrophysical phenomena. We take an effective field theory eft approach to unifying existing proposals for the origin of cosmic acceleration and its connection to cosmological observations. I argue that some important elements of the current cosmological model are conventionalist in the sense defined by karl popper. Tsujikawa, dark energy, theory and observations, cambridge university press 2010. Introducing the theoretical ideas, observational methods and results, this textbook.
However, within 95% cl, both of them allow their zero values. Current observations cannot distinguish dark energy features bean and dore prd 69 2003, but future large scale surveys which are deep, z2, such as lsst might well be able to if w. It is thought to make up about 68% of the matterenergy in the universe. Reconstructing the dark matter and dark energy interaction. The other possibility is that gr breaks down on cosmological scales and must be replaced with a more complete theory of gravity. A topological magueijosmolin varying speed of light.
But there are shortcomings with even the leading conservative proposals. The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. Introduction to dark energy isapp heidelberg luca amendola, university of heidelberg. Dark energy and modified scale covariant theory of. Cosmologists call them dark matter and dark energy, and in this thesis we are concerned with investigations into both of these most mysterious parts of the universe. Dark energy, the mysterious cause of the accelerating expansion of the universe, is one of the most important fields of research in astrophysics and cosmology today. The approach is comprehensive with rigorous mathematical theory and relevant astronomical. Theory of dark energy and dark matter 3 we proceed as follows. We investigated the evolution of the background expansion and the growth rate of the matter density fluctuations in the scalar field. Pdf luca amendola, shinji tsujikawa dark energy theory and. Inflation theory proposes that a vacuum energy engorged the universe by a factor of 1026. Reconstructing the dark matter and dark energy interaction scenarios from observations. E4 at least 60 orders of magnitude too large for a bare cc to cancel these. Dark matter and dark energy a challenge for modern.
In this book we will explore this dark enigma and introduce the cosmologists toolkit of observations and techniques that allow us to confront different theories on the dark universe. Astronomical observations and cosmological theory suggest that the composition of the universe is remarkably rich and complex. This proposed vacuum energy at the dawn of the universe may have something in common with dark energy. Ill explain why i believe that, to truly understand the dark universe, we will need some new physics that will. Einsteins cosmological constant particle physics provides sources for such a constant but the energy scales associated with particle physics scale cutoffs and transitions give energy densities. We point out that, in our theory of local scale invariance, there is an inherent.
The latest observations of exploding stars could call into question the cosmological constant explanation of dark energy. Describes the status of cosmic microwave background, largescale structure and highredshift type iasupernovae observations. The quantities that connect the observations to theory. Typically in science, you do not come up with an extension of your theory or propose a new hypothesis unless new data contradicts existing ideas. The unknown nature of dark energy remains the most intriguing problem of physics and cosmology of the last decade. The question of the physics behindcosmicacceleration is thus one of the most intriguing open questions in modern physics. Here, it is seen that though this modified theory may be a cause of the accelerated expansion it cannot totally outcast the contribution of dark energy in causing the accelerated expansion. Work done in 20 based on the planck spacecraft observations of the cmb gave a more accurate estimate of 68. The dark energy of the universe jim cline, mcgill university astro night, 21 jan. First, we have shown in ma and wang, 2014a a new cosmology theorem that our universe is a three dimensional sphere and is static, assuming the einstein gen. Dark energy theory and observations luca amendola institut fur theoretische physik, universitat heidelberg osservatorio astronomico di roma shinji. Dark energy is now part of the concordance model of cosmology.
The missing energy the supernova observations call out for some. Albert einstein postulated the equivalence of energy and mass, developed the theory of special relativity, explained the photoelectric effect, and described brownian motion in five papers, all published in 1905, 100 years ago. Selecting this option will search all publications across the scitation platform selecting this option will search all publications for the publishersociety in context. Probing dark energy with theory and observations core.
The wilkinson microwave anisotropy probe wmap spacecraft sevenyear analysis estimated a universe made up of 72. This page intentionally left blank dark energy theory and observations dark energy, the mysterious cause of the accelerating expansion of the universe, is one of the most important fields of research in astrophysics and cosmology today. With the recent dasi observations, the evidence for atness is now quite rm 2. Through a tangled history, dark energy is tied to einsteins cosmological constant. However, the two major constituents of the standard model remain enigmatic. Physical theory currently has no explanation of why the energy of empty space should be precisely zero quantummechanical effects combined with relativity in fact. Enter your mobile number or email address below and well send you a link to download the free kindle app. Hi, i have discovered a theory of dark matter and a theory of dark energy that i exposed as simply as possible, without details of calculation, in 2 videos on youtube with titles theory of dark matter and,theory of dark energy, author thierry delort. History of the dark energy theory of cosmological expansion the observational evidence for dark energy what could it be.
Conversely, astrophysical observations provide one of the most. We then study according to our new theory of dark matter the different possible distributions of dark matter in galaxies and. Natural simplest possibility, consistent with all data to date, is a constant. Then you can start reading kindle books on your smartphone, tablet, or computer. Luca amendola, shinji tsujikawa dark energy theory and observations. These coherent oscillations transform the energy originally stored in the axion. Dark energy theory and observations dark energy, the mysterious cause of the accelerating expansion of the universe, is one of the most important. Taking up four model universes we study the behaviour and contribution of dark energy to the accelerated expansion of the universe, in the modified scale covariant theory of gravitation. Pdf on jun 28, 20, alicia bueno belloso and others published the nature. Making use of the hp and the dimensional analysis, we derive the general formula of the energy density of hde. Astrophysics cosmology and nongalactic astrophysics. Dark energy theory and observations cosmology, relativity and. With a compact introduction to cosmological perturbation theory, fundamental to understand the main observational probes of dark matter and dark energy. Pdf luca amendola, shinji tsujikawa dark energy theory.
We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type ia supernovae constitution compilation, the baryon acoustic oscillation measurement from the sloan digital sky survey, the cosmic microwave background measurement given by the sevenyear wilkinson microwave anisotropy probe. Contents of universe by mass observational evidence for dark matter any nonluminous component of the universe. Introducing the theoretical ideas, observational methods and results, this textbook is ideally suited to graduate courses on dark energy, and will also supplement advanced cosmology courses. Leading dark energy theory incompatible with new measurement. This option allows users to search by publication, volume and page selecting this option will search the current publication in context. Pdf this work provides the current theory and observations behind the cosmological phenomenon of dark energy. The dark side includes 25% of the total massenergy in the form of dark matter binding together galaxies and other largescale structures, and 70% in the form of dark energy driving galaxies.
Then, we describe the properties of hde model, in which the future event horizon is chosen as the characteristic. For this purpose, we carried out the statistical bayesian analysis, and. First, and starting from the concept of the speed of light being an average over multifractals, we use magueijosmolins ingenious revision of einsteins special relativity famous formula e mc2 to a doubly special formula which includes the planck. Concerning the video theory of dark matter that must be seen in first, i first expose completely the astronomical observations having led. Dark energy theory and observations semantic scholar.
In other words, why did scientists begin proposing that there was a new thing we call dark energy and why is it called dark energy. Author links open overlay panel weiqiang yang a narayan banerjee b andronikos paliathanasis c. Theorists have proposed a dozen of models well matching the observational data. We will first present constraints from a host of recent dataon the. The darkenergy story begins in 1998, when two independent teams of astronomers were. This work provides the current theory and observations behind the cosmological phenomenon of dark energy. These elements include dark matter and dark energy. New research casts a shadow on the existence of dark energy. We also find that all nonearly dark energy models we consider can be modeled extremely wellby a simple linear equation of. Einsteins general theory of relativity, such as a new longrange force that moderates the strength of gravity.