Dark matter, dark energy, and the expansion of the universe by michael howard 1032012 type ia supernovae it was discovered that these supernovae had a smaller redshift than would be expected. H02n1100 abstract a power machine based on universal gravitation features use of a special structure to collect energy and use of highintensity magnet whose unused surface has been shielded to limit speed, both of which are combined to generate physical motion. She has worked on advancing the methods for interpreting dark energy data, and developing optimal observational strategies for probing the nature of dark energy. Illuminating dark energy with the joint efficient darkenergy. Banks and dine argue that all explanations for dark. Schedule hps 2580 cosmology university of pittsburgh. She has worked on advancing the methods for interpreting dark energy data, and developing optimal observational strategies for probing th.
Current supernova, cmb, and lss data already rule out dark energy models with dark energy densities that vary greatly with time. Impact of high chargecollection efficiencies and dark. The cause for the observed acceleration in the expansion of the universe is unknown, and referred to as dark energy for convenience. The existence of gravitationally repulsive dark energy would have dramatic consequences for fundamental physics. A precise measurement of dark energy density as a free function of cosmic time will have a fundamental impact on particle physics and cosmology. Yun wang is a senior research scientist at ipac, california institute of technology. Measuring time dependence of dark energy density from type ia. Jedi joint efficient dark energy investigation is a candidate implementation of the nasadoe joint dark energy mission jdem. To assess the ability of current and future supernova data to constrain the properties of the dark energy, we allow its density to have arbitrary time dependence. We report on the relationships between the energyloss processes in the dark, chargecollection efficiency and photocurrent densityvoltage characteristics of dyesensitized solar cells dsscs.
The first part is for preliminary knowledge, including general relativity, modern cosmology, etc. Dark energy search with supernovae, in proceedings of the 6th ucla symposium on dark matter and dark energy, 2004 new dark energy constraints from supernovae, microwave background and galaxy clustering phys. Yun is the pi of atlas probe, a proposed mission concept for a nasa probeclass mission for breakthrough. Yun wang is a leading expert in dark energy research, with over thirty refereed publications on this subject. Although wang also covers the basic cosmology background and includes a short chapter on models to explain cosmic acceleration, her book focuses much more on the major observational methods for probing dark energysupernovae, largescale structure, weak lensing, and clusters. We also perform a statefinder diagnostic to the holographic dark energy model in cases of different c which given by three fits to observational data. She has worked on advancing the methods for interpreting dark energy data, and developing optimal observational strategies for. To determine the nature of dark energy from observational data, it is important that we use modelindependent and optimal methods.
Yun wang, 2282011 observational methods for probing dark energy measure two functions of redshift z. We should minimize gravitational lensing effect on supernovae by. Because these telescopes are looking back in time the fact that the redshift was smaller than expected means that they were moving slower in the past. Observational constraints on dark energy and cosmic. Dark energy isbn 9783527409419 pdf epub yun wang ebook. In article number 1704779, xianfu wang, chenglin yan, and co. Illuminating dark energy with the joint efficient dark. Sometimes chance conspires and the laws of randomness cast good things in our direction at a time that seems exactly right. Dark energy by yun wang overdrive rakuten overdrive.
Nonconventional free energy devices examples and practical. This would allow us to determine whether the dark energy is a cosmological constant or some exotic form of energy with a timedependent density. This book introduces the current state of research on dark energy. Furthermore, gc and wl constrain different aspects in the modi. Guido damico, marc kamionkowski, and kris sigurdson, dark matter astrophysics, ch. In this paper, we study the possibility of building twofield models of dark energy with equation of state across 1. Citescore values are based on citation counts in a given year e. Designing a spacebased galaxy redshift survey to probe dark energy.
The desitter space associated with the accelerating universe poses serious problems for the formulation of string theory 15. Impact of high chargecollection efficiencies and dark energy. The cause for the observed acceleration in the expansionof the universe is unknown,and. One curious issue that arises from this set of hypotheses is that light traversing the cosmic bubbles between galaxy filaments should be redshifted due to the lower background energy of the dark energy vacuum. Unbiased estimate of dark energy density from type ia. 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. Measuring time dependence of dark energy density from type ia supernova data. White 1951 studied galaxy formation in the lambdacold dark matter model. Dark matter and dark energy by michael wang on prezi.
Dark matter and dark energy laura baudis, yun wang on. Dark energy wiley online books wiley online library. Yun wang, 32011 at the last scattering of cmb photons, the acoustic oscillations in the photonbaryon fluid became frozen. Dreamscape futurecycle 2012, published februrary 20. In this video ill be sharing my understanding from channeling how are dimensions cerated, what is dark energy, what is light energy and how in. Jedi joint efficient darkenergy investigation is a candidate implementation of the nasadoe joint dark energy mission jdem. Illuminating the nature of dark energy is one of the most important challenges in cosmology today. This is what happened to me this week, when i extracted from two giant reading pilescolumns over four feet high, weaving even now a little precariously behind my deska thin chapbook by a poet i hadnt heard of, the carp, by yun wang.
Baryon acoustic oscillations bao in the galaxy power spectrum allows us to extract the scale of the comoving sound horizon at recombination, a cosmological. Aug 02, 2014 in this video ill be sharing my understanding from channeling how are dimensions cerated, what is dark energy, what is light energy and how in combinations they can create fisical reality. Though the concept of a dark energy driven accelerating universe was introduced by the author in 1997, to date dark energy itself, as described below has remained a paradigm. The universe appears to be expanding at an accelerating rate, driven by a mechanism called dark energy. Yun wang has developed strategies for optimizing future surveys to probe dark energy, and created a mission concept for the nasadoe joint dark energy mission jdem, the joint efficient dark energy investigation jedi, and served as the principal investigator of jedi. Dimensionless dark energy densities and estimated with and, respectively see fig. Dark matter and dark energy michael wang dark energy dark matter dark energy is a type of energy that accelerates the expansion of the universe there are two supposed forms of dark energy cosmologicaldark energy is spread evenly throughout the universe dynamiccertain. Yun wang has developed strategies for optimizing future surveys to probe dark energy, and created a mission concept for the nasadoe joint dark energy mission jdem, the joint efficient darkenergy investigation jedi, and served as the principal investigator of jedi. Yun wang 1964 uses supernova and galactic redshift data to probe dark energy. It will also provide definitive measurements on dark energy, explore dusty regions of the inner milky way, and probe the formation. We will compare the various surveys using both the dark energy task force detf.
Observational probes of dark energy yun wang homer l. Dark energy by miao li, xiaodong li, shuang wang, yi wang. Jeffrey weeks 1956 used cosmic background patterns to determine the topology of the universe. Dark matter, dark energy, and the expansion of the universe. Black horse chinese literature today, vulume 3, no. We make a comparison for ten typical, popular dark energy models according to their capabilities of fitting the current observational data. Measuring time dependence of dark energy density from type. The carp by wang, yun and a great selection of related books, art and collectibles available now at. Observational approaches to understanding dark energy.
This leads to an equation of state for the dark energy, w x zp x z. Probing the nature of cosmic acceleration yun wang all three methods, as they have different systematic errors. Deng wang and xinhe mengexploring uncertainties in dark energy constraints using current observational data with planck 2015 distance priors yun wang and mi daithis content was downloaded from ip address 157. Although wang also covers the basic cosmology background and includes a short chapter on models to explain cosmic acceleration, her book focuses much more on the major observational methods for probing dark energy supernovae, largescale structure, weak lensing, and clusters. Designing a spacebased galaxy redshift survey to probe.
Recent physics of the dark universe articles elsevier. Clusters of galaxies provide an independent and complementary method to probe dark energy. Theory of dark energy and dark matter 3 we proceed as follows. The university of oklahoma department of physics and astronomy. The statefinder diagrams characterize the properties of the holographic dark energy and show the discrimination between this scenario and other dark energy models.
Jan 27, 2010 yun wang is a leading expert in dark energy research, with over thirty refereed publications on this subject. Dark matter and dark energy michael wang dark energy dark matter dark energy is a type of energy that accelerates the expansion of the universe there are two supposed forms of dark energy cosmological dark energy is spread evenly throughout the universe dynamiccertain. Miroslav halza hypothesizes the existence of a trinity of subatomic builder. Designing a spacebased galaxy redshift survey to probe dark. Najla said dark energy why what binning w binning strategy correlations analysis results conclusions dark energy equation of state. Dark energy constraints from baryon acoustic oscillations. The european physical society has awarded the the cdf and dzero collaborations with the prestigous 2019 high energy and particle physics prize for the discovery of the top quark and the detailed measurement of its properties. Scientists using nasa s hubble space telescope have discovered that dark energy is not a new constituent of space, but rather has been present for most of the universes history. Fluxaveraging has the most significant effect when we allow dark energy density function xz to be a free functions given by the cubic spline of. Exploring uncertainties in dark energy constraints using current. We should probe dark energy using its density allowed to be a free function of cosmic time instead of its equation of state.
The most conservative suggestions are that the universe is filled with a uniform sea of quantum zeropoint energy, or a condensate of new particles that have a mass that. Specifically we will consider two classes of models. Nonconventional free energy devices examples and practical applications compiled by adolf schneider, nov. Nasa nasas hubble finds evidence for dark energy in the. This acclaimed book by yun wang is available at in several formats for your ereader. Dark energy and light energy ying yang that creates. The gain in dark energy fom of an optimized spacebased survey is most dramatic over groundbased surveys when dark energy density is allowed to be a free function parametrized by its values at equally spaced redshift values extending to z 2 thus allowing a modelindependent measurement of dark energy see table 2. The nature of dark energy is largely unknown and needs to be derived from observation of its effects. Aacenter for astrophysics, department of physics, 225 nieuwland science. Unbiased estimate of dark energy density from type ia supernova data yun wang and geoffrey lovelace department of physics and astronomy, room 1, nielsen hall, university of oklahoma, norman, ok 730190225.
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