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Sample records for big bang model

  1. The Whole Shebang: How Science Produced the Big Bang Model.

    Science.gov (United States)

    Ferris, Timothy

    2002-01-01

    Offers an account of the accumulation of evidence that has led scientists to have confidence in the big bang theory of the creation of the universe. Discusses the early work of Ptolemy, Copernicus, Kepler, Galileo, and Newton, noting the rise of astrophysics, and highlighting the birth of the big bang model (the cosmic microwave background theory…

  2. Inhomogeneous Big Bang Cosmology

    CERN Document Server

    Wagh, S M

    2002-01-01

    In this letter, we outline an inhomogeneous model of the Big Bang cosmology. For the inhomogeneous spacetime used here, the universe originates in the infinite past as the one dominated by vacuum energy and ends in the infinite future as the one consisting of "hot and relativistic" matter. The spatial distribution of matter in the considered inhomogeneous spacetime is {\\em arbitrary}. Hence, observed structures can arise in this cosmology from suitable "initial" density contrast. Different problems of the standard model of Big Bang cosmology are also resolved in the present inhomogeneous model. This inhomogeneous model of the Big Bang Cosmology predicts "hot death" for the universe.

  3. The Big Bang Singularity

    Science.gov (United States)

    Ling, Eric

    The big bang theory is a model of the universe which makes the striking prediction that the universe began a finite amount of time in the past at the so called "Big Bang singularity." We explore the physical and mathematical justification of this surprising result. After laying down the framework of the universe as a spacetime manifold, we combine physical observations with global symmetrical assumptions to deduce the FRW cosmological models which predict a big bang singularity. Next we prove a couple theorems due to Stephen Hawking which show that the big bang singularity exists even if one removes the global symmetrical assumptions. Lastly, we investigate the conditions one needs to impose on a spacetime if one wishes to avoid a singularity. The ideas and concepts used here to study spacetimes are similar to those used to study Riemannian manifolds, therefore we compare and contrast the two geometries throughout.

  4. Expansion of the Universe - Standard Big Bang Model

    CERN Document Server

    Roos, Matts

    2008-01-01

    After a brief introduction to the sixteenth and seventeenth century views of the Universe and the nineteenth century paradox of Olbers, we start the history of the cosmic expansion with Hubble's epochal discovery of the recession velocities of spiral galaxies. By then Einstein's theories of relativity were well known, but no suitable metric was known. Prior to introducing General Relativity we embark on a non-chronological derivation of the Robertson-Walker metric directly from Special Relativity and the Minkowski metric endowed with a Gaussian curvature. This permits the definition of all relativistic distance measures needed in observational astronomy. Only thereafter do we come to General Relativity, and describe some of its consequences: gravitational lensing, black holes, various tests, and the cornerstone of the standard Big Bang model, the Friedmann-Lemaitre equations. Going backwards in time towards Big Bang we first have to trace the thermal history, and then understand the needs for a cosmic inflati...

  5. The big bang

    Science.gov (United States)

    Silk, Joseph

    Our universe was born billions of years ago in a hot, violent explosion of elementary particles and radiation - the big bang. What do we know about this ultimate moment of creation, and how do we know it? Drawing upon the latest theories and technology, this new edition of The big bang, is a sweeping, lucid account of the event that set the universe in motion. Joseph Silk begins his story with the first microseconds of the big bang, on through the evolution of stars, galaxies, clusters of galaxies, quasars, and into the distant future of our universe. He also explores the fascinating evidence for the big bang model and recounts the history of cosmological speculation. Revised and updated, this new edition features all the most recent astronomical advances, including: Photos and measurements from the Hubble Space Telescope, Cosmic Background Explorer Satellite (COBE), and Infrared Space Observatory; the latest estimates of the age of the universe; new ideas in string and superstring theory; recent experiments on neutrino detection; new theories about the presence of dark matter in galaxies; new developments in the theory of the formation and evolution of galaxies; the latest ideas about black holes, worm holes, quantum foam, and multiple universes.

  6. Big bang nucleosynthesis - The standard model and alternatives

    Science.gov (United States)

    Schramm, David N.

    1991-01-01

    The standard homogeneous-isotropic calculation of the big bang cosmological model is reviewed, and alternate models are discussed. The standard model is shown to agree with the light element abundances for He-4, H-2, He-3, and Li-7 that are available. Improved observational data from recent LEP collider and SLC results are discussed. The data agree with the standard model in terms of the number of neutrinos, and provide improved information regarding neutron lifetimes. Alternate models are reviewed which describe different scenarios for decaying matter or quark-hadron induced inhomogeneities. The baryonic density relative to the critical density in the alternate models is similar to that of the standard model when they are made to fit the abundances. This reinforces the conclusion that the baryonic density relative to critical density is about 0.06, and also reinforces the need for both nonbaryonic dark matter and dark baryonic matter.

  7. Big bang nucleosynthesis: The standard model and alternatives

    Science.gov (United States)

    Schramm, David N.

    1991-01-01

    Big bang nucleosynthesis provides (with the microwave background radiation) one of the two quantitative experimental tests of the big bang cosmological model. This paper reviews the standard homogeneous-isotropic calculation and shows how it fits the light element abundances ranging from He-4 at 24% by mass through H-2 and He-3 at parts in 10(exp 5) down to Li-7 at parts in 10(exp 10). Furthermore, the recent large electron positron (LEP) (and the stanford linear collider (SLC)) results on the number of neutrinos are discussed as a positive laboratory test of the standard scenario. Discussion is presented on the improved observational data as well as the improved neutron lifetime data. Alternate scenarios of decaying matter or of quark-hadron induced inhomogeneities are discussed. It is shown that when these scenarios are made to fit the observed abundances accurately, the resulting conlusions on the baryonic density relative to the critical density, omega(sub b) remain approximately the same as in the standard homogeneous case, thus, adding to the robustness of the conclusion that omega(sub b) approximately equals 0.06. This latter point is the driving force behind the need for non-baryonic dark matter (assuming omega(sub total) = 1) and the need for dark baryonic matter, since omega(sub visible) is less than omega(sub b).

  8. A Big Bang model of human colorectal tumor growth.

    Science.gov (United States)

    Sottoriva, Andrea; Kang, Haeyoun; Ma, Zhicheng; Graham, Trevor A; Salomon, Matthew P; Zhao, Junsong; Marjoram, Paul; Siegmund, Kimberly; Press, Michael F; Shibata, Darryl; Curtis, Christina

    2015-03-01

    What happens in early, still undetectable human malignancies is unknown because direct observations are impractical. Here we present and validate a 'Big Bang' model, whereby tumors grow predominantly as a single expansion producing numerous intermixed subclones that are not subject to stringent selection and where both public (clonal) and most detectable private (subclonal) alterations arise early during growth. Genomic profiling of 349 individual glands from 15 colorectal tumors showed an absence of selective sweeps, uniformly high intratumoral heterogeneity (ITH) and subclone mixing in distant regions, as postulated by our model. We also verified the prediction that most detectable ITH originates from early private alterations and not from later clonal expansions, thus exposing the profile of the primordial tumor. Moreover, some tumors appear 'born to be bad', with subclone mixing indicative of early malignant potential. This new model provides a quantitative framework to interpret tumor growth dynamics and the origins of ITH, with important clinical implications.

  9. The Big Bang

    CERN Multimedia

    Moods, Patrick

    2006-01-01

    How did the Universe begin? The favoured theory is that everything - space, time, matter - came into existence at the same moment, around 13.7 thousand million years ago. This event was scornfully referred to as the "Big Bang" by Sir Fred Hoyle, who did not believe in it and maintained that the Universe had always existed.

  10. Was There A Big Bang?

    CERN Document Server

    Soberman, Robert K

    2008-01-01

    The big bang hypothesis is widely accepted despite numerous physics conflicts. It rests upon two experimental supports, galactic red shift and the cosmic microwave background. Both are produced by dark matter, shown here to be hydrogen dominated aggregates with a few percent of helium nodules. Scattering from these non-radiating intergalactic masses produce a red shift that normally correlates with distance. Warmed by our galaxy to an Eigenvalue of 2.735 K, drawn near the Earth, these bodies, kept cold by ablation, resonance radiate the Planckian microwave signal. Several tests are proposed that will distinguish between this model and the big bang.

  11. Finding the big bang

    CERN Document Server

    Page, Lyman A; Partridge, R Bruce

    2009-01-01

    Cosmology, the study of the universe as a whole, has become a precise physical science, the foundation of which is our understanding of the cosmic microwave background radiation (CMBR) left from the big bang. The story of the discovery and exploration of the CMBR in the 1960s is recalled for the first time in this collection of 44 essays by eminent scientists who pioneered the work. Two introductory chapters put the essays in context, explaining the general ideas behind the expanding universe and fossil remnants from the early stages of the expanding universe. The last chapter describes how the confusion of ideas and measurements in the 1960s grew into the present tight network of tests that demonstrate the accuracy of the big bang theory. This book is valuable to anyone interested in how science is done, and what it has taught us about the large-scale nature of the physical universe.

  12. Big Bang 8

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Band 8 vermittelt auf verständliche Weise Relativitätstheorie, Kern- und Teilchenphysik (und deren Anwendungen in der Kosmologie und Astrophysik), Nanotechnologie sowie Bionik.

  13. Big Bang 6

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Der Band 6 RG behandelt die Gravitation, Schwingungen und Wellen, Thermodynamik und eine Einführung in die Elektrizität anhand von Alltagsbeispielen und Querverbindungen zu anderen Disziplinen.

  14. Big Bang 5

    CERN Document Server

    Apolin, Martin

    2007-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. Der Band 5 RG behandelt die Grundlagen (Maßsystem, Größenordnungen) und die Mechanik (Translation, Rotation, Kraft, Erhaltungssätze).

  15. Big Bang 7

    CERN Document Server

    Apolin, Martin

    2008-01-01

    Physik soll verständlich sein und Spaß machen! Deshalb beginnt jedes Kapitel in Big Bang mit einem motivierenden Überblick und Fragestellungen und geht dann von den Grundlagen zu den Anwendungen, vom Einfachen zum Komplizierten. Dabei bleibt die Sprache einfach, alltagsorientiert und belletristisch. In Band 7 werden neben einer Einführung auch viele aktuelle Aspekte von Quantenmechanik (z. Beamen) und Elektrodynamik (zB Elektrosmog), sowie die Klimaproblematik und die Chaostheorie behandelt.

  16. Big bang darkleosynthesis

    Directory of Open Access Journals (Sweden)

    Gordan Krnjaic

    2015-12-01

    Full Text Available In a popular class of models, dark matter comprises an asymmetric population of composite particles with short range interactions arising from a confined nonabelian gauge group. We show that coupling this sector to a well-motivated light mediator particle yields efficient darkleosynthesis, a dark-sector version of big-bang nucleosynthesis (BBN, in generic regions of parameter space. Dark matter self-interaction bounds typically require the confinement scale to be above ΛQCD, which generically yields large (≫MeV/dark-nucleon binding energies. These bounds further suggest the mediator is relatively weakly coupled, so repulsive forces between dark-sector nuclei are much weaker than Coulomb repulsion between standard-model nuclei, which results in an exponential barrier-tunneling enhancement over standard BBN. Thus, darklei are easier to make and harder to break than visible species with comparable mass numbers. This process can efficiently yield a dominant population of states with masses significantly greater than the confinement scale and, in contrast to dark matter that is a fundamental particle, may allow the dominant form of dark matter to have high spin (S≫3/2, whose discovery would be smoking gun evidence for dark nuclei.

  17. An embedding for the big bang

    Science.gov (United States)

    Wesson, Paul S.

    1994-01-01

    A cosmological model is given that has good physical properties for the early and late universe but is a hypersurface in a flat five-dimensional manifold. The big bang can therefore be regarded as an effect of a choice of coordinates in a truncated higher-dimensional geometry. Thus the big bang is in some sense a geometrical illusion.

  18. Passport to the Big Bang

    CERN Multimedia

    De Melis, Cinzia

    2013-01-01

    Le 2 juin 2013, le CERN inaugure le projet Passeport Big Bang lors d'un grand événement public. Affiche et programme. On 2 June 2013 CERN launches a scientific tourist trail through the Pays de Gex and the Canton of Geneva known as the Passport to the Big Bang. Poster and Programme.

  19. The Last Big Bang

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, Austin D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Meade, Roger Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-13

    As one of the very few people in the world to give the “go/no go” decision to detonate a nuclear device, Austin “Mac” McGuire holds a very special place in the history of both the Los Alamos National Laboratory and the world. As Commander of Joint Task Force Unit 8.1.1, on Christmas Island in the spring and summer of 1962, Mac directed the Los Alamos data collection efforts for twelve of the last atmospheric nuclear detonations conducted by the United States. Since data collection was at the heart of nuclear weapon testing, it fell to Mac to make the ultimate decision to detonate each test device. He calls his experience THE LAST BIG BANG, since these tests, part of Operation Dominic, were characterized by the dramatic displays of the heat, light, and sounds unique to atmospheric nuclear detonations – never, perhaps, to be witnessed again.

  20. Neutrino oscillations and Big Bang Nucleosynthesis

    OpenAIRE

    Bell, Nicole F.

    2001-01-01

    We outline how relic neutrino asymmetries may be generated in the early universe via active-sterile neutrino oscillations. We discuss possible consequences for big bang nucleosynthesis, within the context of a particular 4-neutrino model.

  1. Big Bang of Massenergy and Negative Big Bang of Spacetime

    Science.gov (United States)

    Cao, Dayong

    2017-01-01

    There is a balance between Big Bang of Massenergy and Negative Big Bang of Spacetime in the universe. Also some scientists considered there is an anti-Big Bang who could produce the antimatter. And the paper supposes there is a structure balance between Einstein field equation and negative Einstein field equation, a balance between massenergy structure and spacetime structure, a balance between an energy of nucleus of the stellar matter and a dark energy of nucleus of the dark matter-dark energy, and a balance between the particle and the wave-a balance system between massenergy (particle) and spacetime (wave). It should explain of the problems of the Big Bang. http://meetings.aps.org/Meeting/APR16/Session/M13.8

  2. Big Bang Nucleosynthesis: 2015

    CERN Document Server

    Cyburt, Richard H; Olive, Keith A; Yeh, Tsung-Han

    2015-01-01

    Big-bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. We briefly overview the essentials of this physics, and present new calculations of light element abundances through li6 and li7, with updated nuclear reactions and uncertainties including those in the neutron lifetime. We provide fits to these results as a function of baryon density and of the number of neutrino flavors, N_nu. We review recent developments in BBN, particularly new, precision Planck cosmic microwave background (CMB) measurements that now probe the baryon density, helium content, and the effective number of degrees of freedom, n_eff. These measurements allow for a tight test of BBN and of cosmology using CMB data alone. Our likelihood analysis convolves the 2015 Planck data chains with our BBN output and observational data. Adding astronomical measurements of light elements strengthens the power of BBN. We include a ...

  3. Relic neutrino asymmetries and big bang nucleosynthesis in a four neutrino model

    OpenAIRE

    Bell, N. F.; Foot, R.; Volkas, R. R.

    1998-01-01

    Oscillations between ordinary and sterile neutrinos can generate large neutrino asymmetries in the early universe. These asymmetries can significantly affect big bang nucleosynthesis (BBN) through modification of nuclear reaction rates. We study this phenomenon within a model consisting of the three ordinary neutrinos plus one sterile neutrino that can be motivated by the neutrino anomalies and the dark matter problem. We calculate how the lepton asymmetries produced evolve at temperatures wh...

  4. Quantum nature of the big bang.

    Science.gov (United States)

    Ashtekar, Abhay; Pawlowski, Tomasz; Singh, Parampreet

    2006-04-14

    Some long-standing issues concerning the quantum nature of the big bang are resolved in the context of homogeneous isotropic models with a scalar field. Specifically, the known results on the resolution of the big-bang singularity in loop quantum cosmology are significantly extended as follows: (i) the scalar field is shown to serve as an internal clock, thereby providing a detailed realization of the "emergent time" idea; (ii) the physical Hilbert space, Dirac observables, and semiclassical states are constructed rigorously; (iii) the Hamiltonian constraint is solved numerically to show that the big bang is replaced by a big bounce. Thanks to the nonperturbative, background independent methods, unlike in other approaches the quantum evolution is deterministic across the deep Planck regime.

  5. An origin of the universe: a model alternative to Big Bang

    OpenAIRE

    Mercik, Andrzej; Mercik, Szymon

    2006-01-01

    We propose a new approach to the model of an origin of the universe built by Oscar Klein and Hannes Alfv\\'{e}n. Some modifications of assumptions underlying the model result in a possible scenario of the universe creation consistent with observations. We explain the large scale structre of the universe and we estimate the Hubble constant value as well as the number of galaxies in the universe. The model does not require many assumptions made in the model based on the Big Bang idea.

  6. Big Bang riddles and their revelations

    CERN Document Server

    Magueijo, J; Magueijo, Joao; Baskerville, Kim

    1999-01-01

    We describe how cosmology has converged towards a beautiful model of the Universe: the Big Bang Universe. We praise this model, but show there is a dark side to it. This dark side is usually called ``the cosmological problems'': a set of coincidences and fine tuning features required for the Big Bang Universe to be possible. After reviewing these ``riddles'' we show how they have acted as windows into the very early Universe, revealing new physics and new cosmology just as the Universe came into being. We describe inflation, pre Big Bang, and varying speed of light theories. At the end of the millennium, these proposals are seen respectively as a paradigm, a tentative idea, and outright speculation.

  7. Was the Big Bang hot?

    Science.gov (United States)

    Wright, E. L.

    1983-01-01

    Techniques for verifying the spectrum defined by Woody and Richards (WR, 1981), which serves as a base for dust-distorted models of the 3 K background, are discussed. WR detected a sharp deviation from the Planck curve in the 3 K background. The absolute intensity of the background may be determined by the frequency dependence of the dipole anisotropy of the background or the frequency dependence effect in galactic clusters. Both methods involve the Doppler shift; analytical formulae are defined for characterization of the dipole anisotropy. The measurement of the 30-300 GHz spectra of cold galactic dust may reveal the presence of significant amounts of needle-shaped grains, which would in turn support a theory of a cold Big Bang.

  8. How quantum is the big bang?

    Science.gov (United States)

    Bojowald, Martin

    2008-06-06

    When quantum gravity is used to discuss the big bang singularity, the most important, though rarely addressed, question is what role genuine quantum degrees of freedom play. Here, complete effective equations are derived for isotropic models with an interacting scalar to all orders in the expansions involved. The resulting coupling terms show that quantum fluctuations do not affect the bounce much. Quantum correlations, however, do have an important role and could even eliminate the bounce. How quantum gravity regularizes the big bang depends crucially on properties of the quantum state.

  9. 淀粉Big Bang!

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Big Bang,也叫"大爆炸",指的是宇宙诞生时期从密度极大且温度极高的太初状态开始发生不断膨胀的过程。换句话说,从Big Bang开始,我们现在的宇宙慢慢形成了。0K,从本期开始,"少电"将在微博引发Big Bang!——淀粉大爆炸!具体怎么爆呢?我想,看到本页版式的你已经明白了七八分了吧?

  10. D-branes in a Big Bang/Big Crunch Universe: Nappi-Witten Gauged WZW Model

    CERN Document Server

    Hikida, Y; Panigrahi, K L; Hikida, Yasuaki; Nayak, Rashmi R.; Panigrahi, Kamal L.

    2005-01-01

    We study D-branes in the Nappi-Witten model, which is a gauged WZW model based on (SL(2,R) x SU(2)) / (U(1) x U(1)). The model describes a four dimensional space-time consisting of cosmological regions with big bang/big crunch singularities and static regions with closed time-like curves. The aim of this paper is to investigate by D-brane probes whether there are pathologies associated with the cosmological singularities and the closed time-like curves. We first classify D-branes in a group theoretical way, and then examine DBI actions for effective theories on the D-branes. In particular, we show that D-brane metric from the DBI action does not include singularities, and wave functions on the D-branes are well behaved even in the presence of closed time-like curves.

  11. A Big Bang Lab

    Science.gov (United States)

    Scheider, Walter

    2005-01-01

    The February 2005 issue of The Science Teacher (TST) reminded everyone that by learning how scientists study stars, students gain an understanding of how science measures things that can not be set up in lab, either because they are too big, too far away, or happened in a very distant past. The authors of "How Far are the Stars?" show how the…

  12. The Standard Model Higgs as the origin of the hot Big Bang

    CERN Document Server

    Figueroa, Daniel G.

    2017-01-01

    If the Standard Model (SM) Higgs is weakly coupled to the inflationary sector, the Higgs is expected to be universally in the form of a condensate towards the end of inflation. The Higgs decays rapidly after inflation -- via non-perturbative effects -- into an out-of-equilibrium distribution of SM species, which thermalize soon afterwards. If the post-inflationary equation of state of the universe is stiff, $w \\simeq +1$, the SM species eventually dominate the total energy budget. This provides a natural origin for the relativistic thermal plasma of SM species, required for the onset the `hot Big Bang' era. The viability of this scenario requires the inflationary Hubble scale $H_*$ to be lower than the instability scale for Higgs vacuum decay, the Higgs not to generate too large curvature perturbations at cosmological scales, and the SM dominance to occur before Big Bang Nucleosynthesis. We show that successful reheating into the SM can only be obtained in the presence of a non-minimal coupling to gravity $\\x...

  13. The Standard Model Higgs as the origin of the hot Big Bang

    Science.gov (United States)

    Figueroa, Daniel G.; Byrnes, Christian T.

    2017-04-01

    If the Standard Model (SM) Higgs is weakly coupled to the inflationary sector, the Higgs is expected to be universally in the form of a condensate towards the end of inflation. The Higgs decays rapidly after inflation - via non-perturbative effects - into an out-of-equilibrium distribution of SM species, which thermalize soon afterwards. If the post-inflationary equation of state of the universe is stiff, w ≃ + 1, the SM species eventually dominate the total energy budget. This provides a natural origin for the relativistic thermal plasma of SM species, required for the onset of the 'hot Big Bang' era. The viability of this scenario requires the inflationary Hubble scale H* to be lower than the instability scale for Higgs vacuum decay, the Higgs not to generate too large curvature perturbations at cosmological scales, and the SM dominance to occur before Big Bang Nucleosynthesis. We show that successful reheating into the SM can only be obtained in the presence of a non-minimal coupling to gravity ξ ≳ 1, with a reheating temperature of TRH ≳ O (1010)ξ 3 / 2(H* /1014 GeV) 2 GeV.

  14. Big bang nucleosynthesis: Present status

    Science.gov (United States)

    Cyburt, Richard H.; Fields, Brian D.; Olive, Keith A.; Yeh, Tsung-Han

    2016-01-01

    Big bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. A brief overview of the essentials of this physics is given, and new calculations presented of light-element abundances through 6Li and 7Li, with updated nuclear reactions and uncertainties including those in the neutron lifetime. Fits are provided for these results as a function of baryon density and of the number of neutrino flavors Nν. Recent developments are reviewed in BBN, particularly new, precision Planck cosmic microwave background (CMB) measurements that now probe the baryon density, helium content, and the effective number of degrees of freedom Neff. These measurements allow for a tight test of BBN and cosmology using CMB data alone. Our likelihood analysis convolves the 2015 Planck data chains with our BBN output and observational data. Adding astronomical measurements of light elements strengthens the power of BBN. A new determination of the primordial helium abundance is included in our likelihood analysis. New D/H observations are now more precise than the corresponding theoretical predictions and are consistent with the standard model and the Planck baryon density. Moreover, D/H now provides a tight measurement of Nν when combined with the CMB baryon density and provides a 2 σ upper limit Nνpointing to new physics. This paper concludes with a look at future directions including key nuclear reactions, astronomical observations, and theoretical issues.

  15. The Biological Big Bang model for the major transitions in evolution

    Science.gov (United States)

    Koonin, Eugene V

    2007-01-01

    previously developed concepts of the emergence of protein folds by recombination of small structural units and origin of viruses and cells from a pre-cellular compartmentalized pool of recombining genetic elements. The model is extended to encompass other major transitions. It is proposed that bacterial and archaeal phyla emerged independently from two distinct populations of primordial cells that, originally, possessed leaky membranes, which made the cells prone to rampant gene exchange; and that the eukaryotic supergroups emerged through distinct, secondary endosymbiotic events (as opposed to the primary, mitochondrial endosymbiosis). This biphasic model of evolution is substantially analogous to the scenario of the origin of universes in the eternal inflation version of modern cosmology. Under this model, universes like ours emerge in the infinite multiverse when the eternal process of exponential expansion, known as inflation, ceases in a particular region as a result of false vacuum decay, a first order phase transition process. The result is the nucleation of a new universe, which is traditionally denoted Big Bang, although this scenario is radically different from the Big Bang of the traditional model of an expanding universe. Hence I denote the phase transitions at the end of each inflationary epoch in the history of life Biological Big Bangs (BBB). Conclusion A Biological Big Bang (BBB) model is proposed for the major transitions in life's evolution. According to this model, each transition is a BBB such that new classes of biological entities emerge at the end of a rapid phase of evolution (inflation) that is characterized by extensive exchange of genetic information which takes distinct forms for different BBBs. The major types of new forms emerge independently, via a sampling process, from the pool of recombining entities of the preceding generation. This process is envisaged as being qualitatively different from tree-pattern cladogenesis. Reviewers This article

  16. The Biological Big Bang model for the major transitions in evolution

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2007-08-01

    of evolution incorporates the previously developed concepts of the emergence of protein folds by recombination of small structural units and origin of viruses and cells from a pre-cellular compartmentalized pool of recombining genetic elements. The model is extended to encompass other major transitions. It is proposed that bacterial and archaeal phyla emerged independently from two distinct populations of primordial cells that, originally, possessed leaky membranes, which made the cells prone to rampant gene exchange; and that the eukaryotic supergroups emerged through distinct, secondary endosymbiotic events (as opposed to the primary, mitochondrial endosymbiosis. This biphasic model of evolution is substantially analogous to the scenario of the origin of universes in the eternal inflation version of modern cosmology. Under this model, universes like ours emerge in the infinite multiverse when the eternal process of exponential expansion, known as inflation, ceases in a particular region as a result of false vacuum decay, a first order phase transition process. The result is the nucleation of a new universe, which is traditionally denoted Big Bang, although this scenario is radically different from the Big Bang of the traditional model of an expanding universe. Hence I denote the phase transitions at the end of each inflationary epoch in the history of life Biological Big Bangs (BBB. Conclusion A Biological Big Bang (BBB model is proposed for the major transitions in life's evolution. According to this model, each transition is a BBB such that new classes of biological entities emerge at the end of a rapid phase of evolution (inflation that is characterized by extensive exchange of genetic information which takes distinct forms for different BBBs. The major types of new forms emerge independently, via a sampling process, from the pool of recombining entities of the preceding generation. This process is envisaged as being qualitatively different from tree

  17. Fixing the Big Bang Theory's Lithium Problem

    Science.gov (United States)

    Kohler, Susanna

    2017-02-01

    How did our universe come into being? The Big Bang theory is a widely accepted and highly successful cosmological model of the universe, but it does introduce one puzzle: the cosmological lithium problem. Have scientists now found a solution?Too Much LithiumIn the Big Bang theory, the universe expanded rapidly from a very high-density and high-temperature state dominated by radiation. This theory has been validated again and again: the discovery of the cosmic microwave background radiation and observations of the large-scale structure of the universe both beautifully support the Big Bang theory, for instance. But one pesky trouble-spot remains: the abundance of lithium.The arrows show the primary reactions involved in Big Bang nucleosynthesis, and their flux ratios, as predicted by the authors model, are given on the right. Synthesizing primordial elements is complicated! [Hou et al. 2017]According to Big Bang nucleosynthesis theory, primordial nucleosynthesis ran wild during the first half hour of the universes existence. This produced most of the universes helium and small amounts of other light nuclides, including deuterium and lithium.But while predictions match the observed primordial deuterium and helium abundances, Big Bang nucleosynthesis theory overpredicts the abundance of primordial lithium by about a factor of three. This inconsistency is known as the cosmological lithium problem and attempts to resolve it using conventional astrophysics and nuclear physics over the past few decades have not been successful.In a recent publicationled by Suqing Hou (Institute of Modern Physics, Chinese Academy of Sciences) and advisorJianjun He (Institute of Modern Physics National Astronomical Observatories, Chinese Academy of Sciences), however, a team of scientists has proposed an elegant solution to this problem.Time and temperature evolution of the abundances of primordial light elements during the beginning of the universe. The authors model (dotted lines

  18. Lemaitre's Big Bang

    CERN Document Server

    Luminet, Jean-Pierre

    2015-01-01

    I give an epistemological analysis of the developments of relativistic cosmology from 1917 to 1966, based on the seminal articles by Einstein, de Sitter, Friedmann, Lemaitre, Hubble, Gamow and other historical figures of the field. It appears that most of the ingredients of the present-day standard cosmological model, including the acceleration of the expansion due to a repulsive dark energy, the interpretation of the cosmological constant as vacuum energy or the possible non-trivial topology of space, had been anticipated by Georges Lemaitre, although his articles remain mostly unquoted.

  19. Big-Bang Nucleosynthesis

    CERN Document Server

    Fields, Brian D.; Sarkar, Subir

    2014-01-01

    A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, η, corresponding to the inferred primordial abundances of deuterium and helium-4 is consistent with the independent determination of η from observations of anisotropies in the cosmic microwave background. However the primordial abundance of lithium-7 inferred from observations is significantly below its expected value. Taking systematic uncertainties in the abundance estimates into account, there is overall concordance in the range η=(5.7−6.7)×10−10 at 95% CL (corresponding to a cosmological baryon density ΩBh2=0.021−0.025). The D and He-4 abundances, when combined with the CMB determination of η, provide the bound Nν=3.28±0.28 on the effective number of neutrino species. Other constraints on new physics are discussed briefly.

  20. George and the big bang

    CERN Document Server

    Hawking, Lucy; Parsons, Gary

    2012-01-01

    George has problems. He has twin baby sisters at home who demand his parents’ attention. His beloved pig Freddy has been exiled to a farm, where he’s miserable. And worst of all, his best friend, Annie, has made a new friend whom she seems to like more than George. So George jumps at the chance to help Eric with his plans to run a big experiment in Switzerland that seeks to explore the earliest moment of the universe. But there is a conspiracy afoot, and a group of evildoers is planning to sabotage the experiment. Can George repair his friendship with Annie and piece together the clues before Eric’s experiment is destroyed forever? This engaging adventure features essays by Professor Stephen Hawking and other eminent physicists about the origins of the universe and ends with a twenty-page graphic novel that explains how the Big Bang happened—in reverse!

  1. Baryon symmetric big bang cosmology

    Science.gov (United States)

    Stecker, F. W.

    1978-01-01

    Both the quantum theory and Einsteins theory of special relativity lead to the supposition that matter and antimatter were produced in equal quantities during the big bang. It is noted that local matter/antimatter asymmetries may be reconciled with universal symmetry by assuming (1) a slight imbalance of matter over antimatter in the early universe, annihilation, and a subsequent remainder of matter; (2) localized regions of excess for one or the other type of matter as an initial condition; and (3) an extremely dense, high temperature state with zero net baryon number; i.e., matter/antimatter symmetry. Attention is given to the third assumption, which is the simplest and the most in keeping with current knowledge of the cosmos, especially as pertains the universality of 3 K background radiation. Mechanisms of galaxy formation are discussed, whereby matter and antimatter might have collided and annihilated each other, or have coexisted (and continue to coexist) at vast distances. It is pointed out that baryon symmetric big bang cosmology could probably be proved if an antinucleus could be detected in cosmic radiation.

  2. Georges et le big bang

    CERN Document Server

    Hawking, Lucy; Parsons, Gary

    2011-01-01

    Georges et Annie, sa meilleure amie, sont sur le point d'assister à l'une des plus importantes expériences scientifiques de tous les temps : explorer les premiers instants de l'Univers, le Big Bang ! Grâce à Cosmos, leur super ordinateur, et au Grand Collisionneur de hadrons créé par Éric, le père d'Annie, ils vont enfin pouvoir répondre à cette question essentielle : pourquoi existons nous ? Mais Georges et Annie découvrent qu'un complot diabolique se trame. Pire, c'est toute la recherche scientifique qui est en péril ! Entraîné dans d'incroyables aventures, Georges ira jusqu'aux confins de la galaxie pour sauver ses amis...Une plongée passionnante au coeur du Big Bang. Les toutes dernières théories de Stephen Hawking et des plus grands scientifiques actuels.

  3. Singularities in big-bang cosmology

    Science.gov (United States)

    Penrose, R.

    1988-03-01

    A review of the history of the development of the big bang theory is presented, including the nature of singularities in black holes and their contribution to the study of the origin of the universe. Various models of the origin of the universe, the question of cosmic censorship, and the possible effects of gravitational collapse are examined. The relationship between considerations of quantum gravity and the structure of quantum theory is discussed.

  4. Rotational inhomogeneities from pre-big bang?

    CERN Document Server

    Giovannini, Massimo

    2005-01-01

    The evolution of the rotational inhomogeneities is investigated in the specific framework of four-dimensional pre-big bang models. While minimal (dilaton-driven) scenarios do not lead to rotational fluctuations, in the case of non-minimal (string-driven) models, fluid sources are present in the pre-big bang phase. The rotational modes of the geometry, coupled to the divergenceless part of the velocity field, can then be amplified depending upon the value of the barotropic index of the perfect fluids. In the light of a possible production of rotational inhomogeneities, solutions describing the coupled evolution of the dilaton field and of the fluid sources are scrutinized in both the string and Einstein frames. In semi-realistic scenarios, where the curvature divergences are regularized by means of a non-local dilaton potential, the rotational inhomogeneities are amplified during the pre-big bang phase but they decay later on. Similar analyses can also be performed when a contraction occurs directly in the str...

  5. Relative Energy Associated with a White Hole Model of the Big Bang

    CERN Document Server

    Binbay, F; Salti, M; Acikgoz, Irfan; Binbay, Figen; Salti, Mustafa

    2006-01-01

    A specific Lemaitre-Tolman model of a spherically symmetric non-rotating white hole model with a few adjustable parameters is investigated to calculate the momentum four-vector distribution (due to matter plus fields including gravity) in the teleparallel gravity. The energy-momentum distributions (due to matter and fields including gravity) of a model are found to be zero. The result that the total energy and momentum components of a white hole model of the big bang are zero supports the viewpoints of Albrow and Tryon. It is also independent of the teleparallel dimensionless coupling constant, which means that it is valid in any teleparallel model. The results we obtained support the viewpoint of Lessner that the Moller energy-momentum formulation is a powerful concept to calculate energy and momentum distributions associated with the universe, and sustains the importance of the energy-momentum definitions in the evaluation of the energy-momentum distribution of a given space-time. Furthermore, the results o...

  6. Concordance of X-ray cluster data with big bang nucleosynthesis in mixed dark matter models

    Energy Technology Data Exchange (ETDEWEB)

    Strickland, R.W. [University of Chicago, Chicago, Illinois 60637 (United States); Schramm, D.N. [University of Chicago, Chicago, Illinois 60637 (United States)]|[NASA/Fermilab Theoretical Astrophysics Group, Fermilab, Batavia, Illinois 60510 (United States)

    1997-06-01

    If the hot, X-ray-emitting gas in rich clusters forms a fair sample of the universe as in cold dark matter (CDM) models and the universe is at the critical density {Omega}{sub T}=1, then the data appear to imply a baryon fraction {Omega}{sub b,X} ({Omega}{sub b,X}{equivalent_to}{Omega}{sub b} derived from X-ray cluster data), larger than that predicted by big bang nucleosynthesis (BBN). While other systematic effects such as clumping can lower {Omega}{sub b,X}, in this paper we use an elementary analysis to show that a simple admixture of hot dark matter (HDM; low-mass neutrinos) with CDM to yield mixed dark matter shifts {Omega}{sub b,X} down so that significant overlap with {Omega}{sub b} from BBN can occur for H{sub 0}{approx_lt}73kms{sup {minus}1}Mpc{sup {minus}1}, even without invoking the possible aforementioned effects. The overlap interval is slightly larger for lower mass neutrinos since fewer of them cluster on the scale of the hot X-ray gas. We illustrate this result quantitatively in terms of a simple isothermal model. More realistic velocity dispersion profiles, with less centrally peaked density profiles, imply that fewer neutrinos are trapped and thus further increase the interval of overlap. {copyright} {ital 1997} {ital The American Astronomical Society}

  7. Cosmic relics from the big bang

    Energy Technology Data Exchange (ETDEWEB)

    Hall, L.J.

    1988-12-01

    A brief introduction to the big bang picture of the early universe is given. Dark matter is discussed; particularly its implications for elementary particle physics. A classification scheme for dark matter relics is given. 21 refs., 11 figs., 1 tab.

  8. COBE looks back to the Big Bang

    Science.gov (United States)

    Mather, John C.

    1993-01-01

    An overview is presented of NASA-Goddard's Cosmic Background Explorer (COBE), the first NASA satellite designed to observe the primeval explosion of the universe. The spacecraft carries three extremely sensitive IR and microwave instruments designed to measure the faint residual radiation from the Big Bang and to search for the formation of the first galaxies. COBE's far IR absolute spectrophotometer has shown that the Big Bang radiation has a blackbody spectrum, proving that there was no large energy release after the explosion.

  9. Big-bang nucleosynthesis revisited

    Science.gov (United States)

    Olive, Keith A.; Schramm, David N.; Steigman, Gary; Walker, Terry P.

    1989-01-01

    The homogeneous big-bang nucleosynthesis yields of D, He-3, He-4, and Li-7 are computed taking into account recent measurements of the neutron mean-life as well as updates of several nuclear reaction rates which primarily affect the production of Li-7. The extraction of primordial abundances from observation and the likelihood that the primordial mass fraction of He-4, Y(sub p) is less than or equal to 0.24 are discussed. Using the primordial abundances of D + He-3 and Li-7 we limit the baryon-to-photon ratio (eta in units of 10 exp -10) 2.6 less than or equal to eta(sub 10) less than or equal to 4.3; which we use to argue that baryons contribute between 0.02 and 0.11 to the critical energy density of the universe. An upper limit to Y(sub p) of 0.24 constrains the number of light neutrinos to N(sub nu) less than or equal to 3.4, in excellent agreement with the LEP and SLC collider results. We turn this argument around to show that the collider limit of 3 neutrino species can be used to bound the primordial abundance of He-4: 0.235 less than or equal to Y(sub p) less than or equal to 0.245.

  10. Probing the Big Bang with LEP

    Science.gov (United States)

    Schramm, David N.

    1990-01-01

    It is shown that LEP probes the Big Bang in two significant ways: (1) nucleosynthesis, and (2) dark matter constraints. In the first case, LEP verifies the cosmological standard model prediction on the number of neutrino types, thus strengthening the conclusion that the cosmological baryon density is approximately 6 percent of the critical value. In the second case, LEP shows that the remaining non-baryonic cosmological matter must be somewhat more massive and/or more weakly interacting than the favorite non-baryonic dark matter candidates of a few years ago.

  11. Bugs and the big bang.

    Science.gov (United States)

    Parsons, Jenni

    2008-10-01

    Now that's a cheery thought! Somewhere more than 100 km below the Geneva countryside two parallel beams of subatomic particles are whizzing around a 27 km circuit in opposite directions at about 99% of the speed of light, doing over 11 000 laps per second. Physicists hope to create a 'bang' that won't end the world, but will unlock some of its mysteries. I confess I have never thought of physicists as poets, but they certainly come up with some evocative models to explain the unknown such as 'dark matter', the invisible skeleton stretching through space; or 'dark energy', which drives the expansion of the universe; or the grandiose 'God's particle' (officially named 'Higgs boson') postulated to endow other particles with mass. These are concepts both too large and too small to grasp.

  12. One Second After the Big Bang

    CERN Document Server

    CERN. Geneva

    2014-01-01

    A new experiment called PTOLEMY (Princeton Tritium Observatory for Light, Early-Universe, Massive-Neutrino Yield) is under development at the Princeton Plasma Physics Laboratory with the goal of challenging one of the most fundamental predictions of the Big Bang – the present-day existence of relic neutrinos produced less than one second after the Big Bang. Using a gigantic graphene surface to hold 100 grams of a single-atomic layer of tritium, low noise antennas that sense the radio waves of individual electrons undergoing cyclotron motion, and a massive array of cryogenic sensors that sit at the transition between normal and superconducting states, the PTOLEMY project has the potential to challenge one of the most fundamental predictions of the Big Bang, to potentially uncover new interactions and properties of the neutrinos, and to search for the existence of a species of light dark matter known as sterile neutrinos.

  13. Generating Ekpyrotic Curvature Perturbations Before the Big Bang

    CERN Document Server

    Lehners, J L; Steinhardt, P J; Turok, N G; Fadden, Paul Mc; Lehners, Jean-Luc; Steinhardt, Paul J.; Turok, Neil

    2007-01-01

    We analyze a general mechanism for producing a nearly scale-invariant spectrum of cosmological curvature perturbations during a contracting phase preceding a big bang, that can be entirely described using 4d effective field theory. The mechanism, based on first producing entropic perturbations and then converting them to curvature perturbations, can be naturally incorporated in cyclic and ekpyrotic models in which the big bang is modelled as a brane collision, as well as other types of cosmological models with a pre-big bang phase. We show that the correct perturbation amplitude can be obtained and that the scalar spectral tilt n tends to range from slightly blue to red, with 0.97 < n < 1.02 for the simplest models, a range compatible with current observations but shifted by a few per cent towards the blue compared to the prediction of the simplest, large-field inflationary models.

  14. The Big Bang Nucleosynthesis limit on $N_{\

    CERN Document Server

    Lisi, E; Villante, F L

    1999-01-01

    Recently we presented a simple method for determining the correlated uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. We now extend this approach to consider departures from the Standard Model, in particular to constrain any new light degrees of freedom present in the thermal plasma during nucleosynthesis. Since the observational situation regarding the inferred primordial abundances has not yet stabilized, we present illustrative bounds on the equivalent number of neutrino species N_nu for various combinations of individual abundance determinations. Our 95% C.L. bounds on N_nu range between 2 and 4, and can easily be reevaluated using the technique provided when the abundances are known more accurately.

  15. The Big Bang (one more time)

    CERN Multimedia

    Spotts, P

    2002-01-01

    For 20 years, Paul Steinhardt has played a key role in helping to write and refine the inflationary "big bang" origin of the universe. But over the past few years, he decided to see if he could come up with a plausible alternative to the prevailing notion (1 page).

  16. Lifting gear crucial in Big Bang experiment

    CERN Multimedia

    2007-01-01

    "On November 26 2007, the most complex scientific instrument ever built will be turned on in an attempt to rerun the Big Bang - but i would never have got off the ground - litteraly - without the hundreds of hoists and cranes on site." (1/2 page)

  17. "Big Bang" project put off to 2008

    CERN Multimedia

    Evans, Robert

    2007-01-01

    "First tests in a scientific project aimed at solving myteries of the universe and the "Big Bang" that created it have been put off from November to late April or early May next year, an official said on Wednesday" (1/2 page)

  18. Antigravity and the big crunch/big bang transition

    Science.gov (United States)

    Bars, Itzhak; Chen, Shih-Hung; Steinhardt, Paul J.; Turok, Neil

    2012-08-01

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  19. Antigravity and the big crunch/big bang transition

    Energy Technology Data Exchange (ETDEWEB)

    Bars, Itzhak [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-2535 (United States); Chen, Shih-Hung [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada); Department of Physics and School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States); Steinhardt, Paul J., E-mail: steinh@princeton.edu [Department of Physics and Princeton Center for Theoretical Physics, Princeton University, Princeton, NJ 08544 (United States); Turok, Neil [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada)

    2012-08-29

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  20. Antigravity and the big crunch/big bang transition

    CERN Document Server

    Bars, Itzhak; Steinhardt, Paul J; Turok, Neil

    2011-01-01

    We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang transition by contracting to zero size, passing through a brief antigravity phase, shrinking to zero size again, and re-emerging into an expanding normal gravity phase. The result may be useful for the construction of complete bouncing cosmologies like the cyclic model.

  1. Beyond the Friedmann-Lemaatre-Robertson-Walker Big Bang Singularity

    Institute of Scientific and Technical Information of China (English)

    Cristi Stoica

    2012-01-01

    Einstein's equation,in its standard form,breaks down at the Big Bang singularity.A new version,equivalent to Einstein's whenever the latter is defined,but applicable in wider situations,is proposed.The new equation remains smooth at the Big Bang singularity of the Friedmann-Lemaatre-Robertson-Walker model.It is a tensor equation defined in terms of the Ricci part of the Riemann curvature.It is obtained by taking the Kulkarni-Nomizu product between Einstein's equation and the metric tensor.

  2. New Cosmic Center Universe Model Matches Eight of Big Bang's Major Predictions Without The F-L Paradigm

    CERN Document Server

    Gentry, R V

    2003-01-01

    Accompanying disproof of the F-L expansion paradigm eliminates the basis for expansion redshifts, which in turn eliminates the basis for the Cosmological Principle. The universe is not the same everywhere. Instead the spherical symmetry of the cosmos demanded by the Hubble redshift relation proves the universe is isotropic about a nearby universal Center. This is the foundation of the relatively new Cosmic Center Universe (CCU) model, which accounts for, explains, or predicts: (i) The Hubble redshift relation, (ii) a CBR redshift relation that fits all current CBR measurements, (iii) the recently discovered velocity dipole distribution of radiogalaxies, (iv) the well-known time dilation of SNeIa light curves, (v) the Sunyaev-Zeldovich thermal effect, (vi) Olber's paradox, (vii) SN dimming for z 1 an enhanced brightness that fits SN 1997ff measurements, (ix) the existence of extreme redshift (z > 10) objects which, when observed, will further distinguish it from the big bang. The CCU model also plausibly expl...

  3. The new model of the Big Bang and the Universe expansion. A comparison with modern observational data and cosmological theories

    Science.gov (United States)

    Kraiko, A. N.; Valiyev, Kh. F.

    2016-10-01

    The new model of the Big Bang and the Universe expansion is constructed. It is based on solutions in classical and in relativistic statements of problem on the dispersion into the void of the gas compressed into a point or in a finite, but for further negligible, volume. If to restrict in relativistic statement gas speed value v by the speed of light (υ =| v |

  4. Science Big Bang comes to the Alps

    CERN Multimedia

    2008-01-01

    The most extensive and expensive scientific instrument in history is due to start working this summer at Cern, the European particle physics laboratory near Geneva. Two beams of protons will accelerate in opposite directions around a 27km tunnel under the Alpine foothills until they are travelling almost at the speed of light - and then smash together, reproducing on a tiny scale the intense energy of the new-born universe after the inaugural Big Bang 15bn years ago.

  5. Science: Big Bang comes to the Alps

    CERN Multimedia

    Cookson, Clive

    2008-01-01

    "The most extensive and expensive scientific instrument in history is due to start working this summer at CERN, the European particle physics laboratory near Geneva. Two beams of protons will accelerate in opposite directions around a 27 km tunnel under the alpine foothills until they are travelling almost at the speed of light - and then smash together, reproducing on a tiny scale the intense energy of the new-born universe after the inaugural Big Bang 15bn years ago. (1 page)

  6. Light-like Big Bang singularities in string and matrix theories

    CERN Document Server

    Craps, Ben

    2011-01-01

    Important open questions in cosmology require a better understanding of the Big Bang singularity. In string and matrix theories, light-like analogues of cosmological singularities (singular plane wave backgrounds) turn out to be particularly tractable. We give a status report on the current understanding of such light-like Big Bang models, presenting both solved and open problems.

  7. Neutrino statistics and big bang nucleosynthesis

    CERN Document Server

    Dolgov, A D; Smirnov, A Yu

    2005-01-01

    Neutrinos may possibly violate the spin-statistics theorem, and hence obey Bose statistics or mixed statistics despite having spin half. We find the generalized equilibrium distribution function of neutrinos which depends on a single fermi-bose parameter, \\kappa, and interpolates continuously between the bosonic and fermionic distributions when \\kappa changes from -1 to +1. We consider modification of the Big Bang Nucleosynthesis (BBN) in the presence of bosonic or partly bosonic neutrinos. For pure bosonic neutrinos the abundances change (in comparison with the usual Fermi-Dirac case) by -3.2% for He4 (which is equivalent to a decrease of the effective number of neutrinos by \\Delta N_\

  8. Nuclear Receptors, RXR, and the Big Bang.

    Science.gov (United States)

    Evans, Ronald M; Mangelsdorf, David J

    2014-03-27

    Isolation of genes encoding the receptors for steroids, retinoids, vitamin D, and thyroid hormone and their structural and functional analysis revealed an evolutionarily conserved template for nuclear hormone receptors. This discovery sparked identification of numerous genes encoding related proteins, termed orphan receptors. Characterization of these orphan receptors and, in particular, of the retinoid X receptor (RXR) positioned nuclear receptors at the epicenter of the "Big Bang" of molecular endocrinology. This Review provides a personal perspective on nuclear receptors and explores their integrated and coordinated signaling networks that are essential for multicellular life, highlighting the RXR heterodimer and its associated ligands and transcriptional mechanism.

  9. Echoes of Big Bang Found in Galaxies

    Institute of Scientific and Technical Information of China (English)

    Mark; Peplow; 吴铭

    2005-01-01

    想了解宇宙的奥秘吗?英澳等国的天文学家近日共同破解了宇宙大爆炸(BigBang)后物质如何分布的秘密,声称物质非平均分布的原因在于宇宙波纹和重力的共同作用,并对早期雾状宇宙的混沌状态如何发展到如今的状况做出了解释。

  10. Pre - big bang inflation requires fine tuning

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Michael S. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Weinberg, Erick J. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    1997-10-01

    The pre-big-bang cosmology inspired by superstring theories has been suggested as an alternative to slow-roll inflation. We analyze, in both the Jordan and Einstein frames, the effect of spatial curvature on this scenario and show that too much curvature --- of either sign --- reduces the duration of the inflationary era to such an extent that the flatness and horizon problems are not solved. Hence, a fine-tuning of initial conditions is required to obtain enough inflation to solve the cosmological problems.

  11. Possible evidence for dark radiation from Big Bang Nucleosynthesis data

    Energy Technology Data Exchange (ETDEWEB)

    Flambaum, V.V. [New South Wales Univ., School of Physics, Sydney NSW (Australia); Argonne National Laboratory, Physics Div., Argonne, IL (United States); Shuryak, E.V. [State University of New York Stony Brook, Dept. of Physics and Astronomy, NY (United States)

    2006-06-15

    We address the emerging discrepancy between the Big Bang Nucleosynthesis data and standard cosmology, which asks for a bit longer evolution time. If this effect is real, one possible implication (in a framework of brane cosmology model) is that there is a 'dark radiation' component which is negative and makes few percents of ordinary matter density. If so, all scales of this model can be fixed, provided brane-to-bulk leakage problem is solved. (authors)

  12. Big Bang Day : The Great Big Particle Adventure - 3. Origins

    CERN Multimedia

    2008-01-01

    In this series, comedian and physicist Ben Miller asks the CERN scientists what they hope to find. If the LHC is successful, it will explain the nature of the Universe around us in terms of a few simple ingredients and a few simple rules. But the Universe now was forged in a Big Bang where conditions were very different, and the rules were very different, and those early moments were crucial to determining how things turned out later. At the LHC they can recreate conditions as they were billionths of a second after the Big Bang, before atoms and nuclei existed. They can find out why matter and antimatter didn't mutually annihilate each other to leave behind a Universe of pure, brilliant light. And they can look into the very structure of space and time - the fabric of the Universe

  13. Quantization of Big Bang in crypto-Hermitian Heisenberg picture

    CERN Document Server

    Znojil, Miloslav

    2015-01-01

    A background-independent quantization of the Universe near its Big Bang singularity is considered using a drastically simplified toy model. Several conceptual issues are addressed. (1) The observable spatial-geometry characteristics of our empty-space expanding Universe is sampled by the time-dependent operator $Q=Q(t)$ of the distance between two space-attached observers (``Alice and Bob''). (2) For any pre-selected guess of the simple, non-covariant time-dependent observable $Q(t)$ one of the Kato's exceptional points (viz., $t=\\tau_{(EP)}$) is postulated {\\em real-valued}. This enables us to treat it as the time of Big Bang. (3) During our ``Eon'' (i.e., at all $t>\\tau_{(EP)}$) the observability status of operator $Q(t)$ is mathematically guaranteed by its self-adjoint nature with respect to an {\\em ad hoc} Hilbert-space metric $\\Theta(t) \

  14. Big-Bang Nucleosynthesis verifies classical Maxwell-Boltzmann distribution

    CERN Document Server

    Hou, S Q; Parikh, A; Daid, K; Bertulani, C

    2014-01-01

    We provide the most stringent constraint to date on possible deviations from the usually-assumed Maxwell-Boltzmann (MB) velocity distribution for nuclei in the Big-Bang plasma. The impact of non-extensive Tsallis statistics on thermonuclear reaction rates involved in standard models of Big-Bang Nucleosynthesis (BBN) has been investigated. We find that the non-extensive parameter $q$ may deviate by, at most, $|\\delta q|$=6$\\times$10$^{-4}$ from unity for BBN predictions to be consistent with observed primordial abundances; $q$=1 represents the classical Boltzmann-Gibbs statistics. This constraint arises primarily from the {\\em super}sensitivity of endothermic rates on the value of $q$, which is found for the first time. As such, the implications of non-extensive statistics in other astrophysical environments should be explored. This may offer new insight into the nucleosynthesis of heavy elements.

  15. Particle physics catalysis of thermal big bang nucleosynthesis.

    Science.gov (United States)

    Pospelov, Maxim

    2007-06-08

    We point out that the existence of metastable, tau>10(3) s, negatively charged electroweak-scale particles (X-) alters the predictions for lithium and other primordial elemental abundances for A>4 via the formation of bound states with nuclei during big bang nucleosynthesis. In particular, we show that the bound states of X- with helium, formed at temperatures of about T=10(8) K, lead to the catalytic enhancement of 6Li production, which is 8 orders of magnitude more efficient than the standard channel. In particle physics models where subsequent decay of X- does not lead to large nonthermal big bang nucleosynthesis effects, this directly translates to the level of sensitivity to the number density of long-lived X- particles (tau>10(5) s) relative to entropy of nX-/s less, approximately <3x10(-17), which is one of the most stringent probes of electroweak scale remnants known to date.

  16. Big-Bang nucleosynthesis with updated nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Coc, Alain [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse (CSNSM), CNRS/IN2P3, Universite Paris Sud 11, UMR 8609, Batiment 104, F-91405 Orsay Campus (France); Vangioni, Elisabeth, E-mail: Alain.Coc@csnsm.in2p3.f, E-mail: vangioni@iap.f [Institut d' Astrophysique de Paris, UMR-7095 du CNRS, Universite Pierre et Marie Curie, 98 bis bd Arago, 75014 Paris (France)

    2010-01-01

    Primordial nucleosynthesis is one of the three evidences for the Big-Bang model together with the expansion of the Universe and the Cosmic Microwave Background. There is a good global agreement over a range of nine orders of magnitude between abundances of {sup 4}He, D, {sup 3}He and {sup 7}Li deduced from observations and calculated primordial nucleosynthesis. This comparison was used to determine the baryonic density of the Universe. For this purpose, it is now superseded by the analysis of the Cosmic Microwave Background (CMB) radiation anisotropies. Big-Bang nucleosynthesis remains, nevertheless, a valuable tool to probe the physics of the early Universe. However, the yet unexplained, discrepancy between the calculated and observed lithium primordial abundances, has not been reduced, neither by recent nuclear physics experiments, nor by new observations.

  17. Constraining Big Bang lithium production with recent solar neutrino data

    CERN Document Server

    Takács, Marcell P; Szücs, Tamás; Zuber, Kai

    2015-01-01

    The 3He({\\alpha},{\\gamma})7Be reaction affects not only the production of 7Li in Big Bang nucleosynthesis, but also the fluxes of 7Be and 8B neutrinos from the Sun. This double role is exploited here to constrain the former by the latter. A number of recent experiments on 3He({\\alpha},{\\gamma})7Be provide precise cross section data at E = 0.5-1.0 MeV center-of-mass energy. However, there is a scarcity of precise data at Big Bang energies, 0.1-0.5 MeV, and below. This problem can be alleviated, based on precisely calibrated 7Be and 8B neutrino fluxes from the Sun that are now available, assuming the neutrino flavour oscillation framework to be correct. These fluxes and the standard solar model are used here to determine the 3He(alpha,gamma)7Be astrophysical S-factor at the solar Gamow peak, S(23+6-5 keV) = 0.548+/-0.054 keVb. This new data point is then included in a re-evaluation of the 3He({\\alpha},{\\gamma})7Be S-factor at Big Bang energies, following an approach recently developed for this reaction in the c...

  18. Quarks, leptons and the big bang

    CERN Document Server

    Allday, Jonathan

    2016-01-01

    Quarks, Leptons and The Big Bang, Third Edition, is a clear, readable and self-contained introduction to particle physics and related areas of cosmology. It bridges the gap between non-technical popular accounts and textbooks for advanced students. The book concentrates on presenting the subject from the modern perspective of quarks, leptons and the forces between them. This book will be of interest to students, teachers and general science readers interested in fundamental ideas of modern physics. This edition brings the book completely up to date by including advances in particle physics and cosmology, such as the discovery of the Higgs boson, the LIGO gravitational wave discovery and the WMAP and PLANCK results.

  19. L'Univers avant le Big Bang

    CERN Multimedia

    Rouat, Sylvie

    2003-01-01

    "Tout n'a pas commencé par une explosion. L'historie du cosmos avait débuté biena vant le Big Bang, si l'on suit la théorie défendue par les partisans d'une nouvelle cosmologie issue de la mystérieuse théorie des cordes. A l'heure où vacillent les scénarios classiques du XXe siècle, se prépare un grand chamboulement de nos idées sur la naissance de l'Univers et son devenir, sur l'existence possible d'univers parallèles. Des théories séduisantes qui seront mises à l'épreuve au cours de la prochaine décennie" (11 pages)

  20. Big bang photosynthesis and pregalactic nucleosynthesis of light elements

    Science.gov (United States)

    Audouze, J.; Lindley, D.; Silk, J.

    1985-01-01

    Two nonstandard scenarios for pregalactic synthesis of the light elements (H-2, He-3, He-4, and Li-7) are developed. Big bang photosynthesis occurs if energetic photons, produced by the decay of massive neutrinos or gravitinos, partially photodisintegrate He-4 (formed in the standard hot big bang) to produce H-2 and He-3. In this case, primordial nucleosynthesis no longer constrains the baryon density of the universe, or the number of neutrino species. Alternatively, one may dispense partially or completely with the hot big bang and produce the light elements by bombardment of primordial gas, provided that He-4 is synthesized by a later generation of massive stars.

  1. Solution of a Braneworld Big Crunch/Big Bang Cosmology

    CERN Document Server

    McFadden, P; Turok, N G; Fadden, Paul Mc; Steinhardt, Paul J.; Turok, Neil

    2005-01-01

    We solve for the cosmological perturbations in a five-dimensional background consisting of two separating or colliding boundary branes, as an expansion in the collision speed V divided by the speed of light c. Our solution permits a detailed check of the validity of four-dimensional effective theory in the vicinity of the event corresponding to the big crunch/big bang singularity. We show that the four-dimensional description fails at the first nontrivial order in (V/c)^2. At this order, there is nontrivial mixing of the two relevant four-dimensional perturbation modes (the growing and decaying modes) as the boundary branes move from the narrowly-separated limit described by Kaluza-Klein theory to the well-separated limit where gravity is confined to the positive-tension brane. We comment on the cosmological significance of the result and compute other quantities of interest in five-dimensional cosmological scenarios.

  2. The case for the relativistic hot big bang cosmology

    Science.gov (United States)

    Peebles, P. J. E.; Schramm, D. N.; Kron, R. G.; Turner, E. L.

    1991-01-01

    What has become the standard model in cosmology is described, and some highlights are presented of the now substantial range of evidence that most cosmologists believe convincingly establishes this model, the relativistic hot big bang cosmology. It is shown that this model has yielded a set of interpretations and successful predictions that substantially outnumber the elements used in devising the theory, with no well-established empirical contradictions. Brief speculations are made on how the open puzzles and work in progress might affect future developments in this field.

  3. What's in a Name: History and Meanings of the Term "Big Bang"

    CERN Document Server

    Kragh, Helge

    2013-01-01

    The name "big bang" introduced by Fred Hoyle in 1949 is one of the most successful scientific neologisms ever. How did the name originate and how was it received by physicists and astronomers in the period leading up to the hot big bang consensus model in the late 1960s? How did it reflect the meanings of the big bang, a concept that predates the name by nearly two decades? The paper gives a detailed account of names and concepts associated with finite-age cosmological models from the 1920s to the 1970s. It turns out that Hoyle's celebrated name has a richer and more surprising history than commonly assumed and also that the literature on modern cosmology and its history includes many common mistakes and errors. By following the story of "big bang" a new dimension is added to the historical understanding of the emergence of modern cosmology.

  4. Big Bang test delayed at CERN's LHC until 2008

    CERN Multimedia

    Atkins, William

    2007-01-01

    "Scientists at the proton-proton Large Hadron Collider (LHC) particle accelerator and collider will postpone a test that could help solve the mystery of what happened a few nanoseconds after the Big Bang." (1 page)

  5. Scientists seek to explain how Big Bang let us live

    CERN Multimedia

    Hawke, N

    2000-01-01

    Scientists at CERN have opened an antimatter factory, the Antiproton Decelerator. They hope to discover why, in the Big Bang, the amount of matter and antimatter produced was not equal, so allowing the universe to exist at all (1 page).

  6. Estudiarán el Big Bang por Internet

    CERN Multimedia

    2007-01-01

    The most powerful Internet, star of the present, goes for another challenge that mixes past and future: to join the scientific world community to clarify the orígines of the universe, the Big Bang. (1/2 page)

  7. Indian microchip for Big Bang research in Geneva

    CERN Document Server

    Bhabani, Soudhriti

    2007-01-01

    "A premier nuclear physics institute here has come up with India's first indigenously designed microchip that will facilitate research on the Big Bang theory in Geneva's CERN, the world's largest particle physics laboratory." (1 page)

  8. L'antimatière questionne toujours le Big Bang

    CERN Multimedia

    Daninos, Franck

    2005-01-01

    A few moments after the Big Bang, matter and antimatter were created in the same quantities. But, the actual Universe is made only from matter. Will the problem of disappearance of the antimatter be solved? (4 pages)

  9. Big-Bang Nucleosynthesis in comparison with observed helium and deuterium abundances - possibility of a non-standard model

    CERN Document Server

    Ichimasa, R; Hashimoto, M; Arai, K

    2014-01-01

    Comparing the latest observed abundances of 4He and D, we make a ?2 analysis to see whether it is possible to reconcile primordial nucleosynthesis using up-to-date nuclear data of NACRE II and the mean-life of neutrons. If we adopt the observational data of ${}^4_{}$He by Izotov et al., we find that it is impossible to get reasonable concordance against the standard Big-Bang nucleosynthesis. However, including degenerate neutrinos, we have succeeded in obtaining consistent constraints between the neutrino degeneracy and the baryon-to-photon ratio from detailed comparison of calculated abundances with the observational data of ${}^4_{}$He and D: the baryon-to-photon ratio in units of $10^{-10}$ is found to be in the range 6.02 < $\\eta^{}_{10}$ < 6:54 for the specified parameters of neutrino degeneracy.

  10. The big-bang theory: construction, evolution and status

    CERN Document Server

    Uzan, Jean-Philippe

    2016-01-01

    Over the past century, rooted in the theory of general relativity, cosmology has developed a very successful physical model of the universe: the {\\em big-bang model}. Its construction followed different stages to incorporate nuclear processes, the understanding of the matter present in the universe, a description of the early universe and of the large scale structure. This model has been confronted to a variety of observations that allow one to reconstruct its expansion history, its thermal history and the structuration of matter. Hence, what we refer to as the big-bang model today is radically different from what one may have had in mind a century ago. This construction changed our vision of the universe, both on observable scales and for the universe as a whole. It offers in particular physical models for the origins of the atomic nuclei, of matter and of the large scale structure. This text summarizes the main steps of the construction of the model, linking its main predictions to the observations that bac...

  11. Evidence for Evolution as Support for Big Bang

    Science.gov (United States)

    Gopal-Krishna

    1997-12-01

    With the exception of ZERO, the concept of BIG BANG is by far the most bizarre creation of the human mind. Three classical pillars of the Big Bang model of the origin of the universe are generally thought to be: (i) The abundances of the light elements; (ii) the microwave back-ground radiation; and (iii) the change with cosmic epoch in the average properties of galaxies (both active and non-active types). Evidence is also mounting for redshift dependence of the intergalactic medium, as discussed elsewhere in this volume in detail. In this contribution, I endeavour to highlight a selection of recent advances pertaining to the third category. The widely different levels of confidence in the claimed observational constraints in the field of cosmology can be guaged from the following excerpts from two leading astrophysicists: "I would bet odds of 10 to 1 on the validity of the general 'hot Big Bang' concept as a description of how our universe has evolved since it was around 1 sec. old" -M. Rees (1995), in 'Perspectives in Astrophysical Cosmology' CUP. "With the much more sensitive observations available today, no astrophysical property shows evidence of evolution, such as was claimed in the 1950s to disprove the Steady State theory" -F. Hoyle (1987), in 'Fifty years in cosmology', B. M. Birla Memorial Lecture, Hyderabad, India. The burgeoning multi-wavelength culture in astronomy has provided a tremendous boost to observational cosmology in recent years. We now proceed to illustrate this with a sequence of examples which reinforce the picture of an evolving universe. Also provided are some relevant details of the data used in these studies so that their scope can be independently judged by the readers.

  12. The Big Bang as the Ultimate Traffic Jam

    CERN Document Server

    Jejjala, Vishnu; Minic, Djordje; Tze, Chia-Hsiung

    2009-01-01

    We present a novel solution to the nature and formation of the initial state of the Universe. It derives from the physics of a generally covariant extension of Matrix theory. We focus on the dynamical state space of this background independent quantum theory of gravity and matter, an infinite dimensional, complex non-linear Grassmannian. When this space is endowed with a Fubini--Study-like metric, the associated geodesic distance between any two of its points is zero. This striking mathematical result translates into a physical description of a hot, zero entropy Big Bang. The latter is then seen as a far from equilibrium, large fluctuation driven, metastable ordered transition, a ``freezing by heating'' jamming transition. Moreover, the subsequent unjamming transition could provide a mechanism for inflation while rejamming may model a Big Crunch, the final state of gravitational collapse.

  13. Passport to the Big Bang moves across the road

    CERN Multimedia

    Corinne Pralavorio

    2015-01-01

    The ATLAS platform of the Passport to the Big Bang circuit has been relocated in front of the CERN Reception.   The ATLAS platform of the Passport to the Big Bang, outside the CERN Reception building. The Passport to the Big Bang platform of the ATLAS Experiment has been moved in front of the CERN Reception to make it more visible and accessible. It had to be dismantled and moved from its previous location in the garden of the Globe of Science and Innovation due to the major refurbishment work in progress on the Globe, and is now fully operational in its new location on the other side of the road, in the Main Reception car-park. The Passport to the Big Bang circuit, inaugurated in 2013, comprises ten platforms installed in front of ten CERN sites and aims to help local residents and visitors to the region understand CERN's research. Dedicated Passport to the Big Bang flyers, containing all necessary information and riddles for you to solve, are available at the CERN Rec...

  14. Discovery Of A Major Contradiction In Big Bang Cosmology Points To The New Cosmic Center Universe Model

    CERN Document Server

    Gentry, R V

    2003-01-01

    The BAL z=3.91 quasar's high Fe/O ratio has led to a reexamination of big bang's spacetime expansion postulate and the discovery that it predicts a CBR redshift of z>36000 instead of the widely accepted z~1000. This result leads an expansion-predicted CBR temperature of only T = 0.08K, which is contradicted by the experimental T = 2.73K. Contrary to long-held belief, these results strongly suggest that the F-L expanding spacetime paradigm, with its expansion redshifts, is not the correct relativistic description of the universe. This conclusion agrees with the earlier finding (gr-qc/9806061) that the universe is relativistically governed by the Einstein static spacetime solution of the field equations, not the F-L solution. Disproof of expansion redshifts removes the only support for the Cosmological Principle, thus showing that the spherical symmetry of the cosmos demanded by the Hubble redshift relation can no longer be attributed to the universe being the same everythere. The Cosmological Principle is flaw...

  15. Dark/visible parallel universes and Big Bang nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Bertulani, C. A.; Frederico, T.; Fuqua, J.; Hussein, M. S.; Oliveira, O.; Paula, W. de [Department of Physics and Astronomy, Texas A and M University-Commerce, Commerce TX 75429 (United States); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP (Brazil); Department of Physics and Astronomy, Texas A and M University-Commerce, Commerce TX 75429 (United States); Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05314-970 Sao Paulo, SP (Brazil); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP, Brazil and Departamento de Fisica, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Departamento de Fisica, Instituto Tecnologico de Aeronautica, DCTA 12.228-900, Sao Jose dos Campos, SP (Brazil)

    2012-11-20

    We develop a model for visible matter-dark matter interaction based on the exchange of a massive gray boson called herein the Mulato. Our model hinges on the assumption that all known particles in the visible matter have their counterparts in the dark matter. We postulate six families of particles five of which are dark. This leads to the unavoidable postulation of six parallel worlds, the visible one and five invisible worlds. A close study of big bang nucleosynthesis (BBN), baryon asymmetries, cosmic microwave background (CMB) bounds, galaxy dynamics, together with the Standard Model assumptions, help us to set a limit on the mass and width of the new gauge boson. Modification of the statistics underlying the kinetic energy distribution of particles during the BBN is also discussed. The changes in reaction rates during the BBN due to a departure from the Debye-Hueckel electron screening model is also investigated.

  16. Dark/Visible Parallel Universes and Big Bang Nucleosynthesis

    CERN Document Server

    Bertulani, C A; Fuqua, J; Hussein, M S; Oliveira, O; de Paula, W

    2012-01-01

    We develop a model for visible matter-dark matter interaction based on the exchange of a massive gray boson called herein the Mulato. Our model hinges on the assumption that all known particles in the visible matter have their counterparts in the dark matter. We postulate six families of particles five of which are dark. This leads to the unavoidable postulation of six parallel worlds, the visible one and five invisible worlds. A close study of big bang nucleosynthesis (BBN), baryon asymmetries, cosmic microwave background (CMB) bounds, galaxy dynamics, together with the Standard Model assumptions, help us to set a limit on the mass and width of the new gauge boson. Modification of the statistics underlying the kinetic energy distribution of particles during the BBN is also discussed. The changes in reaction rates during the BBN due to a departure from the Debye-Hueckel electron screening model is also investigated.

  17. Film Presentation: The Big Bang Machine by BBC (2008)

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Professor Brian Cox visits Geneva to take a look around CERN's Large Hadron Collider before the vast, 27km long machine is sealed off and a simulation experiment begins to try to create the conditions that existed a billionth of a second after the Big Bang. Cox is joined by fellow scientists, including CERN theorist John Ellis and Nobel Laureate Leon Lederman from Fermilab, who hope that the LHC will change our understanding of the early Universe and solve some of its mysteries. The Big Bang Machine will be presented on Friday, 15 October from 13:00 to 14:00 in the Council Chamber, Bldg.503 Language: English

  18. Baryon symmetric big-bang cosmology. [matter-antimatter symmetry

    Science.gov (United States)

    Stecker, F. W.

    1978-01-01

    The framework of baryon-symmetric big-bang cosmology offers the greatest potential for deducing the evolution of the universe as a consequence of physical laws and processes with the minimum number of arbitrary assumptions as to initial conditions in the big-bang. In addition, it offers the possibility of explaining the photon-baryon ratio in the universe and how galaxies and galaxy clusters are formed, and also provides the only acceptable explanation at present for the origin of the cosmic gamma ray background radiation.

  19. Capture reactions on C-14 in nonstandard big bang nucleosynthesis

    Science.gov (United States)

    Wiescher, Michael; Gorres, Joachim; Thielemann, Friedrich-Karl

    1990-01-01

    Nonstandard big bang nucleosynthesis leads to the production of C-14. The further reaction path depends on the depletion of C-14 by either photon, alpha, or neutron capture reactions. The nucleus C-14 is of particular importance in these scenarios because it forms a bottleneck for the production of heavier nuclei A greater than 14. The reaction rates of all three capture reactions at big bang conditions are discussed, and it is shown that the resulting reaction path, leading to the production of heavier elements, is dominated by the (p, gamma) and (n, gamma) rates, contrary to earlier suggestions.

  20. A Quantum Dynamic Cosmology Model Without Big Bang%一种无大爆炸量子动态宇宙模型

    Institute of Scientific and Technical Information of China (English)

    邵丹; 邵亮; 邵常贵

    2011-01-01

    According to the loop quantum gravity,calculates and obtains the results of the volume inflation and the metric fluctuation,and a creation way of gravity field is given,during the transition of the spacetime.Using finiteness of the representation of quantum group,a quantum dynamic cosmdogy model without singularity of spacetime is raised,and it is compared with the big bang cosmology model.%依据圈量子引力,计算出空时跃迁体积膨胀和度量起伏的结果,同时给出了引力场的一种生成途径.利用量子群SU 2 q表示的有限性,提出了一种不存在空时奇点的量子动态宇宙模型,并将其与大爆炸宇宙模型做了某些比较.

  1. Quark mass variation constraints from Big Bang nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Bedaque, P; Luu, T; Platter, L

    2010-12-13

    We study the impact on the primordial abundances of light elements created of a variation of the quark masses at the time of Big Bang nucleosynthesis (BBN). In order to navigate through the particle and nuclear physics required to connect quark masses to binding energies and reaction rates in a model-independent way we use lattice QCD data and an hierarchy of effective field theories. We find that the measured {sup 4}He abundances put a bound of {delta}-1% {approx}< m{sub q}/m{sub 1} {approx}< 0.7%. The effect of quark mass variations on the deuterium abundances can be largely compensated by changes of the baryon-to-photon ratio {eta}. Including the bounds on the variation of {eta} coming from WMAP results and some additional assumptions narrows the range of allowed values of {delta}m{sub q}/m{sub q} somewhat.

  2. Big bang nucleosynthesis and the quark-hadron transition

    Science.gov (United States)

    Kurki-Suonio, Hannu; Matzner, Richard A.; Olive, Keith A.; Schramm, David N.

    1990-01-01

    An examination and brief review is made of the effects of quark-hadron transition induced fluctuations on Big Bang nucleosynthesis. It is shown that cosmologically critical densities in baryons are difficult to reconcile with observation, but the traditional baryon density constraints from homogeneous calculations might be loosened by as much as 50 percent, to 0.3 of critical density, and the limit on the number of neutrino flavors remains about N(sub nu) is less than or approximately 4. To achieve baryon densities of greater than or approximately 0.3 of critical density would require initial density contrasts R is much greater the 10(exp e), whereas the simplest models for the transition seem to restrict R to less than of approximately 10(exp 2).

  3. COBE's search for structure in the Big Bang

    Science.gov (United States)

    Soffen, Gerald (Editor); Guerny, Gene (Editor); Keating, Thomas (Editor); Moe, Karen (Editor); Sullivan, Walter (Editor); Truszkowski, Walt (Editor)

    1989-01-01

    The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle.

  4. Response of VIRGO detectors to pre-big-bang gravitons

    CERN Document Server

    Babusci, D; Babusci, Danilo; Giovannini, Massimo

    2001-01-01

    The sensitivity achievable by a pair of VIRGO detectors to stochastic and isotropic gravitational wave backgrounds produced in pre-big-bang models is discussed in view of the development of a second VIRGO interferometer. We describe a semi-analytical technique allowing to compute the signal-to-noise ratio for (monotonic or non-monotonic) logarithmic energy spectra of relic gravitons of arbitrary slope. We apply our results to the case of two correlated and coaligned VIRGO detectors and we compute their achievable sensitivities. We perform our calculations both for the usual case of minimal string cosmological scenario and in the case of a non-minimal scenario where a long dilaton dominated phase is present prior to the onset of the ordinary radiation dominated phase. In this framework, we investigate possible improvements of the achievable sensitivities by selective reduction of the thermal contributions (pendulum and pendulum's internal modes) to the noise power spectra of the detectors. Since a reduction of...

  5. A Guided Inquiry on Hubble Plots and the Big Bang

    Science.gov (United States)

    Forringer, Ted

    2014-01-01

    In our science for non-science majors course "21st Century Physics," we investigate modern "Hubble plots" (plots of velocity versus distance for deep space objects) in order to discuss the Big Bang, dark matter, and dark energy. There are two potential challenges that our students face when encountering these topics for the…

  6. Film Presentation: Big Bang, mes ancêtres et moi

    CERN Multimedia

    2010-01-01

    Big Bang, mes ancêtres et moi, by Franco-German TV producer ARTE (2009)   What do we know about the origins of the world today? This documentary presents a voyage into the mystery of these origins, accompanied by passionate scientists such as paleoanthropologist Pascal Picq, astrophysicist Hubert Reeves, physicist Etienne Klein and quantum gravity theorist Abhay Ashtekar. Organized around three key moments – the birth of the Universe, the appearance of life and the origins of mankind – this investigation takes us to various research areas around the world, including the large underground particle accelerator at CERN. The German version of this film, Big Bang im Labor, will be presented on 1st October. Big Bang, mes ancêtres et moi will be shown on Friday, 24 September from 13:00 to 14:00 in room 222-R-001 Language: French Big Bang im Labor will be shown on Friday, 1 October from 13:00 to 14:00 in the Main Auditorium Language : German   &nbs...

  7. Constructing "Nerdiness": Characterisation in "The Big Bang Theory"

    Science.gov (United States)

    Bednarek, Monika

    2012-01-01

    This paper analyses the linguistic construction of the televisual character Sheldon--the "main nerd" in the sitcom "The Big Bang Theory" (CBS, 2007-), approaching this construction of character through both computerised and "manual" linguistic analysis. More specifically, a computer analysis of dialogue (using concordances and keyword analysis) in…

  8. Neutrino energy transport in weak decoupling and big bang nucleosynthesis

    CERN Document Server

    Grohs, E; Kishimoto, C T; Paris, M W; Vlasenko, A

    2015-01-01

    We calculate the evolution of the early universe through the epochs of weak decoupling, weak freeze-out and big bang nucleosynthesis (BBN) by simultaneously coupling a full strong, electromagnetic, and weak nuclear reaction network with a multi-energy group Boltzmann neutrino energy transport scheme. Such an approach allows a detailed accounting of the evolution of the $\

  9. Recrean el Big Bang a nivel microscópico

    CERN Multimedia

    2007-01-01

    Although the scientists assure that the Universe was created from great explosion or Big Bang, that gave origin to the matter which we know today - including the alive beings - What happened after this strong snap is still a mystery regarding the formation of the cosmos. (1 page)

  10. HydraPower out to make a big bang

    CERN Multimedia

    Revill, John

    2006-01-01

    "An engineering company has provided equipment for a £1.3 billion international project to recreate the conditions of the 'Big Bang". Garry Williams, technical director of hydraPower dynamics, has been asked to return to Switzerland by CERN."

  11. The Big Bang: UK Young Scientists' and Engineers' Fair 2010

    Science.gov (United States)

    Allison, Simon

    2010-01-01

    The Big Bang: UK Young Scientists' and Engineers' Fair is an annual three-day event designed to promote science, technology, engineering and maths (STEM) careers to young people aged 7-19 through experiential learning. It is supported by stakeholders from business and industry, government and the community, and brings together people from various…

  12. EMR implementation: big bang or a phased approach?

    Science.gov (United States)

    Owens, Kathleen

    2008-01-01

    There are two major strategies to implementing an EMR: the big-bang approach and the phased, or incremental, approach. Each strategy has pros and cons that must be considered. This article discusses these approaches and the risks and benefits of each as well as some training strategies that can be used with either approach.

  13. Cosmologie L'Univers avant le Big Bang

    CERN Multimedia

    Rouat, Sylvie

    2003-01-01

    Tout n'a pas commencé par une explosion. L'histoire du cosmos avait débuté bien avant le Big Bang, si l'on suit la théorie défendue par les partisans d'une nouvelle cosmologie issue de la mystérieuse théorie des cordes

  14. Astrophysical Li-7 as a product of big bang nucleosynthesis and galactic cosmic-ray spallation

    Science.gov (United States)

    Olive, Keith A.; Schramm, David N.

    1992-01-01

    The astrophysical Li-7 abundance is considered to be largely primordial, while the Be and B abundances are thought to be due to galactic cosmic ray (GCR) spallation reactions on top of a much smaller big bang component. But GCR spallation should also produce Li-7. As a consistency check on the combination of big bang nucleosynthesis and GCR spallation, the Be and B data from a sample of hot population II stars is used to subtract from the measured Li-7 abundance an estimate of the amount generated by GCR spallation for each star in the sample, and then to add to this baseline an estimate of the metallicity-dependent augmentation of Li-7 due to spallation. The singly reduced primordial Li-7 abundance is still consistent with big bang nucleosynthesis, and a single GCR spallation model can fit the Be, B, and corrected Li-7 abundances for all the stars in the sample.

  15. Astrophysical S-factor for destructive reactions of lithium-7 in big bang nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Komatsubara, Tetsuro; Kwon, YoungKwan; Moon, JunYoung; Kim, Yong-Kyun [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of); Moon, Chang-Bum [Hoseo University, Asan, Chungnam (Korea, Republic of); Ozawa, Akira; Sasa, Kimikazu; Onishi, Takahiro; Yuasa, Toshiaki; Okada, Shunsuke; Saito, Yuta [Division of Physics, University of Tsukuba, Tsukuba, Ibaraki (Japan); Hayakawa, Takehito; Shizuma, Toshiyuki [Japan Atomic Energy Agency, Shirakata Shirane, Tokai, Ibaraki (Japan); Kubono, Shigeru [RIKEN, Hirosawa, Wako, Saitama (Japan); Kusakabe, Motohiko [School of Liberal Arts and Science, Korea Aerospace University (Korea, Republic of); Kajino, Toshitaka [National Astronomical Observatory, Osawa, Mitaka, Tokyo (Japan)

    2014-05-02

    One of the most prominent success with the Big Bang models is the precise reproduction of mass abundance ratio for {sup 4}He. In spite of the success, abundances of lithium isotopes are still inconsistent between observations and their calculated results, which is known as lithium abundance problem. Since the calculations were based on the experimental reaction data together with theoretical estimations, more precise experimental measurements may improve the knowledge of the Big Bang nucleosynthesis. As one of the destruction process of lithium-7, we have performed measurements for the reaction cross sections of the {sup 7}L({sup 3}He,p){sup 9}Be reaction.

  16. 革命者BIG BANG

    Institute of Scientific and Technical Information of China (English)

    刘岩

    2015-01-01

    <正>在鄂尔多斯的繁荣时代,我遇见了那里的一位"意见领袖",因为他从美国回来,见过外面的世界,有着对奢侈品辽阔的见识和独到的品味。他引领着那座神秘财富城市中一个小圈子的购物风潮,他们一块接一块儿地购入Big Bang。那个时候,我并不太清楚他们迷恋这款腕表的原因,直到我一次次地去到巴塞尔表展,一次次地了解到Big Bang的想象力。是的,Big Bang的确充满了魅力。Big Bang进化史2005年Big Bang系列诞生2006年Big Bang全黑"全黑"理念使Big Bang更加纯粹和简洁。Big Bang全黑腕表从表壳到表盘浑然天成的亚光质感和多层次、不同材料融合起来的黑色,蕴含"不可见的可见"之禅意。

  17. Entropy generation and inflation in collision induced pre-big-bang cosmology

    NARCIS (Netherlands)

    Feinstein, A.; Kunze, K.E.; Vazquez-Mozo, M.A.

    2000-01-01

    We study inflation and entropy generation in a recently proposed pre-big-bang model universe produced in a collision of gravitational and dilaton waves. It is shown that enough inflation occurs provided the incoming waves are sufficiently weak. We also find that entropy in this model is dynamically

  18. Fisicos argentinos reproduciran el Big Bang

    CERN Multimedia

    De Ambrosio, Martin

    2008-01-01

    Two groups of argentine physicists from La Plata and Buenos Aires Universities work in a sery of experiments who while recreate the conditions of the big explosion that was at the origin of the universe. (1 page)

  19. Limits to the primordial helium abundance in the baryon-inhomogeneous big bang

    Science.gov (United States)

    Mathews, G. J.; Schramm, D. N.; Meyer, B. S.

    1993-01-01

    The parameter space for baryon inhomogeneous big bang models is explored with the goal of determining the minimum helium abundance obtainable in such models while still satisfying the other light-element constraints. We find that the constraint of (D + He-3)/H less than 10 exp -4 restricts the primordial helium mass fraction from baryon-inhomogeneous big bang models to be greater than 0.231 even for a scenario which optimizes the effects of the inhomogeneities and destroys the excess lithium production. Thus, this modification to the standard big bang as well as the standard homogeneous big bang model itself would be falsifiable by observation if the primordial He-4 abundance were observed to be less than 0.231. Furthermore, a present upper limit to the observed helium mass fraction of Y(obs)(p) less than 0.24 implies that the maximum baryon-to-photon ratio allowable in the inhomogeneous models corresponds to eta less than 2.3 x 10 exp -9 (omega(b) h-squared less than 0.088) even if all conditions are optimized.

  20. Superhorizon curvaton amplitude in inflation and pre-big bang cosmology

    DEFF Research Database (Denmark)

    Sloth, Martin Snoager

    2002-01-01

    the same way. We also discuss the amplitude of the density perturbations, which leads to some interesting constrains on the pre-big bang scenario. It is shown that within a SL(3,R) non-linear sigma model one of the three axions has the right coupling to the dilaton and moduli to yield a flat spectrum...

  1. On the use of big-bang method to generate low-energy structures of atomic clusters modeled with pair potentials of different ranges.

    Science.gov (United States)

    Marques, J M C; Pais, A A C C; Abreu, P E

    2012-02-05

    The efficiency of the so-called big-bang method for the optimization of atomic clusters is analysed in detail for Morse pair potentials with different ranges; here, we have used Morse potentials with four different ranges, from long- ρ = 3) to short-ranged ρ = 14) interactions. Specifically, we study the efficacy of the method in discovering low-energy structures, including the putative global minimum, as a function of the potential range and the cluster size. A new global minimum structure for long-ranged ρ = 3) Morse potential at the cluster size of n= 240 is reported. The present results are useful to assess the maximum cluster size for each type of interaction where the global minimum can be discovered with a limited number of big-bang trials.

  2. Big Bang Day: 5 Particles - 3. The Anti-particle

    CERN Document Server

    Franck Close

    2008-01-01

    Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 3. The Anti-particle. It appears to be the stuff of science fiction. Associated with every elementary particle is an antiparticle which has the same mass and opposite charge. Should the two meet and combine, the result is annihilation - and a flash of light. Thanks to mysterious processes that occurred after the Big Bang there are a vastly greater number of particles than anti-particles. So how could their elusive existence be proved? At CERN particle physicists are crashing together subatomic particles at incredibly high speeds to create antimatter, which they hope will finally reveal what happened at the precise moment of the Big Bang to create the repertoire of elementary particles and antiparticles in existence today.

  3. Discrete gravity and the universe from big crunch to big bang

    CERN Document Server

    Ling, Y

    2003-01-01

    In this paper we present a discretized description of the universe from big crunch to big bang. In this context we find the cosmological singularity can be avoided in a general fashion. However, whether the continuum limit of such discretized theories exists is model dependent. In the case of massless scalar field coupled to gravity with $\\Lambda=0$, the continuum limit can only be achieved by fine tuning the recurrence constant. We regard this failure as the implication that cosmological constant should vary with time. For this reason we replace the massless scalar field by Chaplygin gas which may contribute an effective cosmological constant term with the evolution of the universe. It turns out that the continuum limit can be reached in this case indeed.

  4. Constraining pre big-bang-nucleosynthesis expansion using cosmic antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Schelke, M. [Istituto Nazionale di Fisica Nucleare, Torino (Italy); Catena, R. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Fornengo, N. [Torino Univ. (Italy). Dipt. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Torino (Italy); Masiero, A. [Pavoa Univ. (Italy). Dipt. di Fisica]|[Istituto Nazionale di Fisica Nucleare, Padova (Italy); Pietroni, M. [Istituto Nazionale di Fisica Nucleare, Padova (Italy)

    2006-06-15

    A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity tests, may nevertheless lead to enhancements of the Hubble rate up to many orders of magnitude. In this paper we show that strong bounds on the pre-BBN evolution of the Universe may be derived, under the assumption that dark matter is a thermal relic, by combining the dark matter relic density bound with constraints coming from the production of cosmic-ray antiprotons by dark matter annihilation in the Galaxy. The limits we derive can be sizable and apply to the Hubble rate around the temperature of dark matter decoupling. For dark matter masses lighter than 100 GeV, the bound on the Hubble-rate enhancement ranges from a factor of a few to a factor of 30, depending on the actual cosmological model, while for a mass of 500 GeV the bound falls in the range 50-500. Uncertainties in the derivation of the bounds and situations where the bounds become looser are discussed. We finally discuss how these limits apply to some specific realizations of non-standard cosmologies: a scalar-tensor gravity model, kination models and a Randall-Sundrum D-brane model. (Orig.)

  5. Physicists create a "perfect" way to study the Big Bang

    CERN Multimedia

    2005-01-01

    Physicists have created the state of matter thought to have filled the Universe just a few microseconds after the big bang and found it to be different from what they were expecting: instead of a gas, it is more like a liquid. Understanding why it is a liquid that should take physicists a step closer to explaining the earliest moments of our Universe (1 ½ page)

  6. Adiabatic CMB perturbations in pre-big bang string cosmology

    CERN Document Server

    Enqvist, Kari; Enqvist, Kari; Sloth, Martin S.

    2002-01-01

    We consider the pre-big bang scenario with a massive axion field which starts to dominate energy density when oscillating in an instanton-induced potential and subsequently reheats the universe as it decays into photons, thus creating adiabatic CMB perturbations. We find that the fluctuations in the axion field can give rise to a nearly flat spectrum of adiabatic perturbations with a spectral tilt $\\Delta n$ in the range $-0.1 \\lesssim \\Delta n \\lesssim 0.3$.

  7. Big Bang 6Li nucleosynthesis studied deep underground (LUNA collaboration)

    Science.gov (United States)

    Trezzi, D.; Anders, M.; Aliotta, M.; Bellini, A.; Bemmerer, D.; Boeltzig, A.; Broggini, C.; Bruno, C. G.; Caciolli, A.; Cavanna, F.; Corvisiero, P.; Costantini, H.; Davinson, T.; Depalo, R.; Elekes, Z.; Erhard, M.; Ferraro, F.; Formicola, A.; Fülop, Zs.; Gervino, G.; Guglielmetti, A.; Gustavino, C.; Gyürky, Gy.; Junker, M.; Lemut, A.; Marta, M.; Mazzocchi, C.; Menegazzo, R.; Mossa, V.; Pantaleo, F.; Prati, P.; Rossi Alvarez, C.; Scott, D. A.; Somorjai, E.; Straniero, O.; Szücs, T.; Takacs, M.

    2017-03-01

    The correct prediction of the abundances of the light nuclides produced during the epoch of Big Bang Nucleosynthesis (BBN) is one of the main topics of modern cosmology. For many of the nuclear reactions that are relevant for this epoch, direct experimental cross section data are available, ushering the so-called "age of precision". The present work addresses an exception to this current status: the 2H(α,γ)6Li reaction that controls 6Li production in the Big Bang. Recent controversial observations of 6Li in metal-poor stars have heightened the interest in understanding primordial 6Li production. If confirmed, these observations would lead to a second cosmological lithium problem, in addition to the well-known 7Li problem. In the present work, the direct experimental cross section data on 2H(α,γ)6Li in the BBN energy range are reported. The measurement has been performed deep underground at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400 kV accelerator in the Laboratori Nazionali del Gran Sasso, Italy. The cross section has been directly measured at the energies of interest for Big Bang Nucleosynthesis for the first time, at Ecm = 80, 93, 120, and 133 keV. Based on the new data, the 2H(α,γ)6Li thermonuclear reaction rate has been derived. Our rate is even lower than previously reported, thus increasing the discrepancy between predicted Big Bang 6Li abundance and the amount of primordial 6Li inferred from observations.

  8. American Humor reflected in English Film The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    刘珍

    2016-01-01

    With the accelerated process of globalization, we are able to access to the wide variety of cultural forms from all over the world conveniently. The United States, a typical country of immigrants, enjoys the world's first place of ethnic cultural melt-ing. In this paper, the writer takes popular sitcom, The Big Bang Theory, for example to explore the humorous culture of the United States as well as its sources and characteristics from the perspective of subtitle translation.

  9. Adiabatic CMB perturbations in pre-big bang string cosmology

    DEFF Research Database (Denmark)

    Enqvist, Kari; Sloth, Martin Snoager

    2001-01-01

    We consider the pre-big bang scenario with a massive axion field which starts to dominate energy density when oscillating in an instanton-induced potential and subsequently reheats the universe as it decays into photons, thus creating adiabatic CMB perturbations. We find that the fluctuations...... in the axion field can give rise to a nearly flat spectrum of adiabatic perturbations with a spectral tilt $\\Delta n$ in the range $-0.1 \\lesssim \\Delta n \\lesssim 1$....

  10. Big Bang Nucleosynthesis and the Helium Isotope Ratio

    CERN Document Server

    Cooke, Ryan

    2015-01-01

    The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of this quantity tentatively support new physics beyond the standard model but, historically, this method has suffered from hidden systematic uncertainties. In this letter, I show that a combined measurement of the primordial deuterium abundance and the primordial helium isotope ratio has the potential to provide a complementary and reliable probe of new physics beyond the standard model. Using the recent determination of the primordial deuterium abundance and assuming that the measured pre-solar 3He/4He meteoritic abundance reflects the primordial value, a bound can be placed on the effective number of neutrino species, Neff(BBN) = 3.01 (+0.95 -0.76, with 95 per cent confidence). Although this value of Neff supports the standard model, it is presently unclear if the pre-solar 3...

  11. Big Bang, Blow Up, and Modular Curves: Algebraic Geometry in Cosmology

    CERN Document Server

    Manin, Yuri I

    2014-01-01

    We introduce some algebraic geometric models in cosmology related to the "boundaries" of space--time: Big Bang, Mixmaster Universe, Penrose's crossovers between aeons. We suggest to model the kinematics of Big Bang using the algebraic geometric (or analytic) blow up of a point $x$. This creates a boundary which consists of the projective space of tangent directions to $x$ and possibly of the light cone of $x$. We argue that time on the boundary undergoes the Wick rotation and becomes purely imaginary. The Mixmaster (Bianchi IX) model of the early history of the universe is neatly explained in this picture by postulating that the reverse Wick rotation follows a hyperbolic geodesic connecting imaginary time axis to the real one. Penrose's idea to see the Big Bang as a sign of crossover from "the end of previous aeon" of the expanding and cooling Universe to the "beginning of the next aeon" is interpreted as an identification of a natural boundary of Minkowski space at infinity with the Bing Bang boundary.

  12. Modified big bang nucleosynthesis with non-standard neutron sources

    CERN Document Server

    Coc, Alain; Uzan, Jean-Philippe; Vangioni, Elisabeth

    2014-01-01

    During big bang nucleosynthesis, any injection of extra neutrons around the time of the $^7$Be formation, i.e. at a temperature of order $T \\simeq 50$~keV, can reduce the predicted freeze-out amount of $^7$Be + $^7$Li that otherwise remains in sharp contradiction with the Spite plateau value inferred from the observations of Pop II stars. However, the growing confidence in the primordial D/H determinations puts a strong constraint on any such scenario. We address this issue in detail, analyzing different temporal patterns of neutron injection, such as decay, annihilation, resonant annihilation, and oscillation between mirror and standard model world neutrons. For this latter case, we derive the realistic injection pattern taking into account thermal effects (damping and refraction) in the primordial plasma. If the extra neutron supply is the sole non-standard mechanism operating during the BBN, the suppression of lithium abundance below Li/H~$\\leq 1.9 \\times 10^{-10}$ always leads to the overproduction of deu...

  13. big bang gene modulates gut immune tolerance in Drosophila

    Science.gov (United States)

    Bonnay, François; Cohen-Berros, Eva; Hoffmann, Martine; Kim, Sabrina Y.; Boulianne, Gabrielle L.; Hoffmann, Jules A.; Matt, Nicolas; Reichhart, Jean-Marc

    2013-01-01

    Chronic inflammation of the intestine is detrimental to mammals. Similarly, constant activation of the immune response in the gut by the endogenous flora is suspected to be harmful to Drosophila. Therefore, the innate immune response in the gut of Drosophila melanogaster is tightly balanced to simultaneously prevent infections by pathogenic microorganisms and tolerate the endogenous flora. Here we describe the role of the big bang (bbg) gene, encoding multiple membrane-associated PDZ (PSD-95, Discs-large, ZO-1) domain-containing protein isoforms, in the modulation of the gut immune response. We show that in the adult Drosophila midgut, BBG is present at the level of the septate junctions, on the apical side of the enterocytes. In the absence of BBG, these junctions become loose, enabling the intestinal flora to trigger a constitutive activation of the anterior midgut immune response. This chronic epithelial inflammation leads to a reduced lifespan of bbg mutant flies. Clearing the commensal flora by antibiotics prevents the abnormal activation of the gut immune response and restores a normal lifespan. We now provide genetic evidence that Drosophila septate junctions are part of the gut immune barrier, a function that is evolutionarily conserved in mammals. Collectively, our data suggest that septate junctions are required to maintain the subtle balance between immune tolerance and immune response in the Drosophila gut, which represents a powerful model to study inflammatory bowel diseases. PMID:23378635

  14. big bang gene modulates gut immune tolerance in Drosophila.

    Science.gov (United States)

    Bonnay, François; Cohen-Berros, Eva; Hoffmann, Martine; Kim, Sabrina Y; Boulianne, Gabrielle L; Hoffmann, Jules A; Matt, Nicolas; Reichhart, Jean-Marc

    2013-02-19

    Chronic inflammation of the intestine is detrimental to mammals. Similarly, constant activation of the immune response in the gut by the endogenous flora is suspected to be harmful to Drosophila. Therefore, the innate immune response in the gut of Drosophila melanogaster is tightly balanced to simultaneously prevent infections by pathogenic microorganisms and tolerate the endogenous flora. Here we describe the role of the big bang (bbg) gene, encoding multiple membrane-associated PDZ (PSD-95, Discs-large, ZO-1) domain-containing protein isoforms, in the modulation of the gut immune response. We show that in the adult Drosophila midgut, BBG is present at the level of the septate junctions, on the apical side of the enterocytes. In the absence of BBG, these junctions become loose, enabling the intestinal flora to trigger a constitutive activation of the anterior midgut immune response. This chronic epithelial inflammation leads to a reduced lifespan of bbg mutant flies. Clearing the commensal flora by antibiotics prevents the abnormal activation of the gut immune response and restores a normal lifespan. We now provide genetic evidence that Drosophila septate junctions are part of the gut immune barrier, a function that is evolutionarily conserved in mammals. Collectively, our data suggest that septate junctions are required to maintain the subtle balance between immune tolerance and immune response in the Drosophila gut, which represents a powerful model to study inflammatory bowel diseases.

  15. Effects of anisotropy and spatial curvature on the pre-big-bang scenario

    Science.gov (United States)

    Clancy, Dominic; Lidsey, James E.; Tavakol, Reza

    1998-08-01

    A class of exact, anisotropic cosmological solutions to the vacuum Brans-Dicke theory of gravity is considered within the context of the pre-big-bang scenario. Included in this class are the Bianchi type III, V and VIh models and the spatially isotropic, negatively curved Friedmann-Robertson-Walker universe. The effects of large anisotropy and spatial curvature are determined. In contrast with a negatively curved Friedmann-Robertson-Walker model, there exist regions of the parameter space in which the combined effects of curvature and anisotropy prevent the occurrence of inflation. When inflation is possible, the necessary and sufficient conditions for successful pre-big-bang inflation are more stringent than in the isotropic models. The initial state for these models is established and corresponds in general to a gravitational plane wave.

  16. Making a Big Bang on the small screen

    Science.gov (United States)

    Thomas, Nick

    2010-01-01

    While the quality of some TV sitcoms can leave viewers feeling cheated out of 30 minutes of their lives, audiences and critics are raving about the science-themed US comedy The Big Bang Theory. First shown on the CBS network in 2007, the series focuses on two brilliant postdoc physicists, Leonard and Sheldon, who are totally absorbed by science. Adhering to the stereotype, they also share a fanatical interest in science fiction, video-gaming and comic books, but unfortunately lack the social skills required to connect with their 20-something nonacademic contemporaries.

  17. Constraining axion dark matter with Big Bang Nucleosynthesis

    Directory of Open Access Journals (Sweden)

    Kfir Blum

    2014-10-01

    Full Text Available We show that Big Bang Nucleosynthesis (BBN significantly constrains axion-like dark matter. The axion acts like an oscillating QCD θ angle that redshifts in the early Universe, increasing the neutron–proton mass difference at neutron freeze-out. An axion-like particle that couples too strongly to QCD results in the underproduction of He4 during BBN and is thus excluded. The BBN bound overlaps with much of the parameter space that would be covered by proposed searches for a time-varying neutron EDM. The QCD axion does not couple strongly enough to affect BBN.

  18. Critical geometry of a thermal big bang

    Science.gov (United States)

    Afshordi, Niayesh; Magueijo, João

    2016-11-01

    We explore the space of scalar-tensor theories containing two nonconformal metrics, and find a discontinuity pointing to a "critical" cosmological solution. Due to the different maximal speeds of propagation for matter and gravity, the cosmological fluctuations start off inside the horizon even without inflation, and will more naturally have a thermal origin (since there is never vacuum domination). The critical model makes an unambiguous, nontuned prediction for the spectral index of the scalar fluctuations: nS=0.96478 (64 ) . Considering also that no gravitational waves are produced, we have unveiled the most predictive model on offer. The model has a simple geometrical interpretation as a probe 3-brane embedded in an E AdS2×E3 geometry.

  19. From the Big Bang to the Brain.

    Science.gov (United States)

    Boliek, Carol A.; Lohmeier, Heather

    1999-01-01

    Summarizes research findings that challenge long-standing theories of infant cognition and motor development and proposes alternative theoretical models to describe skill acquisition during the first several years of life. Findings are discussed with respect to research in the area of infant speech physiology and production. (Author/CR)

  20. Primordial beryllium as a big bang calorimeter.

    Science.gov (United States)

    Pospelov, Maxim; Pradler, Josef

    2011-03-25

    Many models of new physics including variants of supersymmetry predict metastable long-lived particles that can decay during or after primordial nucleosynthesis, releasing significant amounts of nonthermal energy. The hadronic energy injection in these decays leads to the formation of ⁹Be via the chain of nonequilibrium transformations: Energy(h)→T, ³He→⁶He, ⁶Li→⁹Be. We calculate the efficiency of this transformation and show that if the injection happens at cosmic times of a few hours the release of O(10 MeV) per baryon can be sufficient for obtaining a sizable ⁹Be abundance. The absence of a plateau structure in the ⁹Be/H abundance down to a O(10⁻¹⁴) level allows one to use beryllium as a robust constraint on new physics models with decaying or annihilating particles.

  1. Big Bang Day : Afternoon Play - Torchwood: Lost Souls

    CERN Multimedia

    2008-01-01

    Martha Jones, ex-time traveller and now working as a doctor for a UN task force, has been called to CERN where they're about to activate the Large Hadron Collider. Once activated, the Collider will fire beams of protons together recreating conditions a billionth of a second after the Big Bang - and potentially allowing the human race a greater insight into what the Universe is made of. But so much could go wrong - it could open a gateway to a parallel dimension, or create a black hole - and now voices from the past are calling out to people and scientists have started to disappear... Where have the missing scientists gone? What is the secret of the glowing man? What is lurking in the underground tunnel? And do the dead ever really stay dead? Lost Souls is a spin-off from the award-winning BBC Wales TV production Torchwood. It stars John Barrowman, Freema Agyeman, Eve Myles, Gareth David-Lloyd, Lucy Montgomery (of Titty Bang Bang) and Stephen Critchlow.

  2. Big Bang nucleosynthesis with a stiff fluid

    CERN Document Server

    Dutta, Sourish

    2010-01-01

    Models that lead to a cosmological stiff fluid component, with a density $\\rho_S$ that scales as $a^{-6}$, where $a$ is the scale factor, have been proposed recently in a variety of contexts. We calculate numerically the effect of such a stiff fluid on the primordial element abundances. Because the stiff fluid energy density decreases with the scale factor more rapidly than radiation, it produces a relatively larger change in the primordial helium-4 abundance than in the other element abundances, relative to the changes produced by an additional radiation component. We show that the helium-4 abundance varies linearly with the density of the stiff fluid at a fixed fiducial temperature. Taking $\\rho_{S10}$ and $\\rho_{R10}$ to be the stiff fluid energy density and the standard density in relativistic particles, respectively, at $T = 10$ MeV, we find that the change in the primordial helium abundance is well-fit by $\\Delta Y_p = 0.00024(\\rho_{S10}/\\rho_{R10})$. The changes in the helium-4 abundance produced by ad...

  3. Particle Creation in Pre-Big-Bang Cosmology theory and observational consequences

    CERN Document Server

    Durrer, R; Sakellariadou, M

    2000-01-01

    We present some phenomenological aspects of the pre-big-bang cosmological model inspired by the duality properties of string theory. In particular, assuming the spatial sections of the homogeneous background geometry to be isotropic, we discuss the quantum production of perturbations of the background fields (gravitons, dilatons, moduli fields), as well as the production of particles which do not contribute to the background, which we call ``seeds''. As such we consider the cases of electromagnetic and axionic seeds. We also discuss their possible observational consequences, for example, we study whether they can provide the origin of primordial galactic magnetic fields, and whether they can generate the initial fluctuations leading to the formation of large-scale structure and the measured cosmic microwave background anisotropies. We finally analyze axion and photon production in four dimensional anisotropic pre-big-bang cosmological models.

  4. Observable gravitational waves in pre-big bang cosmology: an update

    Science.gov (United States)

    Gasperini, M.

    2016-12-01

    In the light of the recent results concerning CMB observations and GW detection we address the question of whether it is possible, in a self-consistent inflationary framework, to simultaneously generate a spectrum of scalar metric perturbations in agreement with Planck data and a stochastic background of primordial gravitational radiation compatible with the design sensitivity of aLIGO/Virgo and/or eLISA. We suggest that this is possible in a string cosmology context, for a wide region of the parameter space of the so-called pre-big bang models. We also discuss the associated values of the tensor-to-scalar ratio relevant to the CMB polarization experiments. We conclude that future, cross-correlated results from CMB observations and GW detectors will be able to confirm or disprove pre-big bang models and—in any case—will impose new significant constraints on the basic string theory/cosmology parameters.

  5. Observable gravitational waves in pre-big bang cosmology: an update

    CERN Document Server

    Gasperini, M

    2016-01-01

    In the light of the recent results concerning CMB observations and GW detection we address the question of whether it is possible, in a self-consistent inflationary framework, to simultaneously generate a spectrum of scalar metric perturbations in agreement with Planck data and a stochastic background of primordial gravitational radiation compatible with the design sensitivity of aLIGO/Virgo and/or eLISA. We show that this is possible in a string cosmology context, for a wide region of the parameter space of the so-called pre-big bang models. We also discuss the associated values of the tensor-to-scalar ratio relevant to the CMB polarization experiments. We conclude that future, cross-correlated results from CMB observations and GW detectors will be able to confirm or disprove pre-big bang models and -- in any case -- will impose new significant constraints on the basic string theory/cosmology parameters.

  6. State of the Universe. If Not with a Big Bang, Then What?

    Science.gov (United States)

    Peterson, Ivars

    1991-01-01

    The Big Bang Theory and alternatives to the Big Bang Theory as an explanation for the origin of the universe are discussed. The importance of the discovery of redshift, the percentage of hydrogen found in old stars, and the existence of a uniform sea of radiation are explained. (KR)

  7. Relationalism Evolves the Universe Through the Big Bang

    CERN Document Server

    Koslowski, Tim A; Sloan, David

    2016-01-01

    We investigate the singularities of homogeneous cosmologies from the point of view of relational (and physically relevant) degrees of freedom of the gravitational field. These do not depend on absolute units of length and duration - thus they do not include the volume and extrinsic curvature. We find that the fully relational dynamical system remains well posed for all physical times, even at the point that would be described as the big bang when evolving present day data backwards in time.This result is achieved in two steps: (1) for solutions which are gravity-dominated near the singularity, we show that any extended physical clock (whose readings only depend on the relational degrees of freedom) will undergo an infinite number of ticks before reaching the big bang. The singularity is therefore pushed into the infinite physical past of any physical clock. (2) for solutions where a stiff matter component (e.g. a massless scalar field) dominates at the singularity, we show that the relational degrees of freed...

  8. From the Big Bang to the Nobel Prize

    Science.gov (United States)

    Mather, John

    2007-04-01

    The Cosmic Background Explorer (COBE) satellite, proposed in 1974 and launched by NASA in 1989, measured the cosmic microwave and infrared background radiation from the Big Bang and everything that happened later. The COBE team made three key measurements: the spectrum of the cosmic microwave background radiation (CMBR) matches a blackbody within 50 ppm (rms), the CMBR is anisotropic, with 10 ppm variations on a 7^o angular scale, and the cosmic infrared background from previously unknown objects is as bright as all the known classes of galaxies. The first measurement confirmed the Hot Big Bang theory with unprecedented accuracy, the second is interpreted as representing quantum mechanical fluctuations in the primordial soup and the seeds of cosmic structure and the basis for the existence of galaxies, and the third is still not fully understood. I will describe the project history, the team members, the hardware and data processing, the major results, and their implications for science, and end with the outlook for future progress with new background measurements and large telescopes.

  9. Cosmic inflation and big bang interpreted as explosions

    CERN Document Server

    Rebhan, Eckhard

    2012-01-01

    It has become common understanding that the recession of galaxies and the corresponding redshift of light received from them can only be explained by an expansion of the space between them and us. In this paper, for the presently favored case of a universe without spatial curvature, it is shown that this interpretation is restricted to comoving coordinates. It is proven by construction that within the framework of general relativity other coordinates exist in relation to which these phenomena can be explained by a motion of the cosmic substrate across space, caused by an explosion like big bang or by inflation preceding an almost big bang. At the place of an observer, this motion occurs without any spatial expansion. It is shown that in these "explosion coordinates" the usual redshift comes about by a Doppler shift and a subsequent gravitational shift. Making use of this interpretation, it can easily be understood why in comoving coordinates light rays of short spatial extensions expand and thus constitute an...

  10. Pre-Big Bang, fundamental Physics and noncyclic cosmologies

    Directory of Open Access Journals (Sweden)

    Gonzalez-Mestres L.

    2014-04-01

    Full Text Available Detailed analyses of WMAP and Planck data can have significant implications for noncyclic pre-Big Bang approaches incorporating a new fundamental scale beyond the Planck scale and, potentially, new ultimate constituents of matter with unconventional basic properties as compared to standard particles. Cosmic-ray experiments at the highest energies can also yield relevant information. Hopefully, future studies will be able to deal with alternatives: i to standard physics for the structure of the physical vacuum, the nature of space-time, the validity of quantum field theory and conventional symmetries, the interpretation of string-like theories...; ii to standard cosmology concerning the origin and evolution of our Universe, unconventional solutions to the cosmological constant problem, the validity of inflationary scenarios, the need for dark matter and dark energy... Lorentz-like symmetries for the properties of matter can then be naturally stable space-time configurations resulting from more general primordial scenarios that incorporate physics beyond the Planck scale and describe the formation and evolution of the physical vacuum. A possible answer to the question of the origin of half-integer spins can be provided by a primordial spinorial space-time with two complex coordinates instead of the conventional four real ones, leading to a really new cosmology. We discuss basic questions and phenomenological topics concerning noncyclic pre-Big Bang cosmologies and potentially related physics.

  11. Big Bang pour le grand public - French version only

    CERN Multimedia

    2004-01-01

    Pour commémorer les 50 ans du CERN et l'année de la physique en 2005, la section de physique de l'Université de Genève ouvre une fois de plus ses portes aux non initiés et organise une série de conférences de vulgarisation scientifique. La première conférence, le 7 décembre prochain aura pour thème le Big-Bang et les observations qui corroborent cette théorie. Le Professeur Georges Meylan, Directeur du Laboratoire d'Astrophysique de l'EPFL, donnera cette conférence destinée à tous les publics. Chacune des conférences débutera par une démonstration de détection de rayons cosmiques dans l'auditoire et l'utilisation de ces signaux venus du fond de l'univers pour créer une ?musique cosmique', en collaboration avec le Professeur Ellberger et Nikolai Mihailov du conservatoire de musique de Genève. Ces processus cosmiques étant aléatoires, chacun de ces concerts sera unique. Les preuves observationnelles du Big Bang par le Professeur Georges Meylan Directeur du Laboratoire d'Astrophysique ...

  12. Re-evaluation of the immunological Big Bang.

    Science.gov (United States)

    Flajnik, Martin F

    2014-11-03

    Classically the immunological 'Big Bang' of adaptive immunity was believed to have resulted from the insertion of a transposon into an immunoglobulin superfamily gene member, initiating antigen receptor gene rearrangement via the RAG recombinase in an ancestor of jawed vertebrates. However, the discovery of a second, convergent adaptive immune system in jawless fish, focused on the so-called variable lymphocyte receptors (VLRs), was arguably the most exciting finding of the past decade in immunology and has drastically changed the view of immune origins. The recent report of a new lymphocyte lineage in lampreys, defined by the antigen receptor VLRC, suggests that there were three lymphocyte lineages in the common ancestor of jawless and jawed vertebrates that co-opted different antigen receptor supertypes. The transcriptional control of these lineages during development is predicted to be remarkably similar in both the jawless (agnathan) and jawed (gnathostome) vertebrates, suggesting that an early 'division of labor' among lymphocytes was a driving force in the emergence of adaptive immunity. The recent cartilaginous fish genome project suggests that most effector cytokines and chemokines were also present in these fish, and further studies of the lamprey and hagfish genomes will determine just how explosive the Big Bang actually was.

  13. Superhorizon curvaton amplitude in inflation and pre-big bang cosmology

    CERN Document Server

    Sloth, M S

    2003-01-01

    We follow the evolution of the curvaton on superhorizon scales and check that the spectral tilt of the curvaton perturbations is unchanged as the curvaton becomes non-relativistic. Both inflation and pre-big bang cosmology can be treated since the curvaton mechanism within the two scenarios works the same way. We also discuss the amplitude of the density perturbations, which leads to some interesting constrains on the pre-big bang scenario. It is shown that within a SL(3,R) non-linear sigma model one of the three axions has the right coupling to the dilaton and moduli to yield a flat spectrum with a high string scale, if a quadratic non-perturbative potential is generated and an intermediate string phase lasts long enough.

  14. The music of the Big Bang the cosmic microwave background and the new cosmology

    CERN Document Server

    Balbi, Amedeo

    2008-01-01

    The cosmic microwave background radiation is the afterglow of the big bang: a tenuous signal, more than 13 billion years old, which carries the answers to many of the questions about the nature of our Universe. It was serendipitously discovered in 1964, and thoroughly investigated in the last four decades by a large number of experiments. Two Nobel Prizes in Physics have already been awarded for research on the cosmic background radiation: one in 1978 to Arno Penzias and Robert Wilson, who first discovered it, the other in 2006, to George Smoot and John Mather, for the results of the COBE satellite. Most cosmological information is encoded in the cosmic background radiation by acoustic oscillations in the dense plasma that filled the primordial Universe: a "music" of the big bang, which cosmologists have long been trying to reconstruct and analyze, in order to distinguish different cosmological models, much like one can distinguish different musical instruments by their timbre and overtones. Only lately, this...

  15. Waarop is sy voetstukke ingesink? - 'n Besinning oor die skepping en die big bang

    Directory of Open Access Journals (Sweden)

    L.C. Bezuidenhout

    1998-08-01

    Full Text Available Through the ages the debate between theology and the natural sciencesconcerning the origin of the universe was turbulent. Today the big bangtheory is almost generally accepted in scientific circles. In this article thedebate between theology and science is evaluated critically. The theologicalimplications of the big bang theory is discussed and the relevance of thecosmogony in Genesis 1 for a modem society is evaluated. Biblical modelsand scientific models of the birth of the cosmos do not have to be in conflictwith each other.

  16. A New Damage Detection Method: Big Bang-Big Crunch (BB-BC Algorithm

    Directory of Open Access Journals (Sweden)

    Zahra Tabrizian

    2013-01-01

    Full Text Available The present paper aims to explore damage assessment methodology based on the changes in dynamic parameters properties of vibration of a structural system. The finite-element model is used to apply at an element level. Reduction of the element stiffness is considered for structural damage. A procedure for locating and quantifying damaged areas of the structure based on the innovative Big Bang-Big Crunch (BB-BC optimization method is developed for continuous variable optimization. For verifying the method a number of damage scenarios for simulated structures have been considered. For the purpose of damage location and severity assessment the approach is applied in three examples by using complete and incomplete modal data. The effect of noise on the accuracy of the results is investigated in some cases. A great unbraced frame with a lot of damaged element is considered to prove the ability of proposed method. More over BB-BC optimization method in damage detection is compared with particle swarm optimizer with passive congregation (PSOPC algorithm. This work shows that BB-BC optimization method is a feasible methodology to detect damage location and severity while introducing numerous advantages compared to referred method.

  17. Out of the white hole: a holographic origin for the Big Bang

    Energy Technology Data Exchange (ETDEWEB)

    Pourhasan, Razieh; Afshordi, Niayesh; Mann, Robert B., E-mail: rpourhasan@perimeterinstitute.ca, E-mail: nafshordi@pitp.ca, E-mail: rbmann@uwaterloo.ca [Department of Physics and Astronomy, University of Waterloo, 200 University Ave. W., Waterloo, Ontario, N2L 3G1 Canada (Canada)

    2014-04-01

    While most of the singularities of General Relativity are expected to be safely hidden behind event horizons by the cosmic censorship conjecture, we happen to live in the causal future of the classical Big Bang singularity, whose resolution constitutes the active field of early universe cosmology. Could the Big Bang be also hidden behind a causal horizon, making us immune to the decadent impacts of a naked singularity? We describe a braneworld description of cosmology with both 4d induced and 5D bulk gravity (otherwise known as Dvali-Gabadadze-Porati, or DGP model), which exhibits this feature: the universe emerges as a spherical 3-brane out of the formation of a 5D Schwarzschild black hole. In particular, we show that a pressure singularity of the holographic fluid, discovered earlier, happens inside the white hole horizon, and thus need not be real or imply any pathology. Furthermore, we outline a novel mechanism through which any thermal atmosphere for the brane, with comoving temperature of ∼20% of the 5D Planck mass can induce scale-invariant primordial curvature perturbations on the brane, circumventing the need for a separate process (such as cosmic inflation) to explain current cosmological observations. Finally, we note that 5D space-time is asymptotically flat, and thus potentially allows an S-matrix or (after minor modifications) an AdS/CFT description of the cosmological Big Bang.

  18. Big Bang nucleosynthesis revisited via Trojan Horse Method measurements

    CERN Document Server

    Pizzone, R G; Bertulani, C A; Spitaleri, C; La Cognata, M; Lalmansingh, J; Lamia, L; Mukhamedzhanov, A; Tumino, A

    2014-01-01

    Nuclear reaction rates are among the most important input for understanding the primordial nucleosynthesis and therefore for a quantitative description of the early Universe. An up-to-date compilation of direct cross sections of 2H(d,p)3H, 2H(d,n)3He, 7Li(p,alpha)4He and 3He(d,p)4He reactions is given. These are among the most uncertain cross sections used and input for Big Bang nucleosynthesis calculations. Their measurements through the Trojan Horse Method (THM) are also reviewed and compared with direct data. The reaction rates and the corresponding recommended errors in this work were used as input for primordial nucleosynthesis calculations to evaluate their impact on the 2H, 3,4He and 7Li primordial abundances, which are then compared with observations.

  19. Big Bang Nucleosynthesis: Probing the First 20 Minutes

    CERN Document Server

    Steigman, G

    2003-01-01

    Within the first 20 minutes of the evolution of the hot, dense, early Universe, astrophysically interesting abundances of deuterium, helium-3, helium-4, and lithium-7 were synthesized by the cosmic nuclear reactor. The primordial abundances of these light nuclides produced during Big Bang Nucleosynthesis (BBN) are sensitive to the universal density of baryons and to the early-Universe expansion rate which at early epochs is governed by the energy density in relativistic particles (``radiation'') such as photons and neutrinos. Some 380 kyr later, when the cosmic background radiation (CBR) radiation was freed from the embrace of the ionized plasma of protons and electrons, the spectrum of temperature fluctuations imprinted on the CBR also depended on the baryon and radiation densities. The comparison between the constraints imposed by BBN and those from the CBR reveals a remarkably consistent picture of the Universe at two widely separated epochs in its evolution. Combining these two probes leads to new and tig...

  20. Cosmologie l'univers avant le Big Bang

    CERN Multimedia

    Larousserie, David

    2003-01-01

    Tout n'a pas commencé par une explosion. L'histoire du cosmos avait débuté bien avant le Big Bang, si l'on suit la théorie défendue par les partisans d'une nouvelle cosmologie issue de la mystérieuse théorie des cords. A l'heure où vacillent les scénarios classiques du XXe siècle, se prépare un grand chamboulement de nos idées sur la naissance de l'Univers et son devenir, sur l'existence possible d'univers parallèles.

  1. Cosmic Heritage Evolution from the Big Bang to Conscious Life

    CERN Document Server

    Shaver, Peter

    2011-01-01

    This book follows the evolutionary trail all the way from the Big Bang 13.7 billion years ago to conscious life today. It is an accessible introductory book written for the interested layperson – anyone interested in the ‘big picture’ coming from modern science. It covers a wide range of topics including the origin and evolution of our universe, the nature and origin of life, the evolution of life including questions of birth and death, the evolution of cognition, the nature of consciousness, the possibility of extraterrestrial life and the future of the universe. The book is written in a narrative style, as these topics are all parts of a single story. It concludes with a discussion on the nature and future of science.  “Peter Shaver has written engagingly for anyone curious about the world we inhabit.  If you'd like to know how the Universe began, where the chemical elements originated, how life may have started on Earth, how man, ants and bacteria are related to each other, or why we humans think...

  2. String theory and pre-big bang cosmology

    Science.gov (United States)

    Gasperini, M.; Veneziano, G.

    2016-09-01

    In string theory, the traditional picture of a Universe that emerges from the inflation of a very small and highly curved space-time patch is a possibility, not a necessity: quite different initial conditions are possible, and not necessarily unlikely. In particular, the duality symmetries of string theory suggest scenarios in which the Universe starts inflating from an initial state characterized by very small curvature and interactions. Such a state, being gravitationally unstable, will evolve towards higher curvature and coupling, until string-size effects and loop corrections make the Universe "bounce" into a standard, decreasing-curvature regime. In such a context, the hot big bang of conventional cosmology is replaced by a "hot big bounce" in which the bouncing and heating mechanisms originate from the quantum production of particles in the high-curvature, large-coupling pre-bounce phase. Here we briefly summarize the main features of this inflationary scenario, proposed a quarter century ago. In its simplest version (where it represents an alternative and not a complement to standard slow-roll inflation) it can produce a viable spectrum of density perturbations, together with a tensor component characterized by a "blue" spectral index with a peak in the GHz frequency range. That means, phenomenologically, a very small contribution to a primordial B-mode in the CMB polarization, and the possibility of a large enough stochastic background of gravitational waves to be measurable by present or future gravitational wave detectors.

  3. String propagation through a big crunch to big bang transition

    Science.gov (United States)

    Tolley, Andrew J.

    2006-06-01

    We consider the propagation of classical and quantum strings on cosmological spacetimes which interpolate from a collapsing phase to an expanding phase. We begin by considering the classical propagation of strings on spacetimes with isotropic and anisotropic cosmological singularities. We find that cosmological singularities fall into two classes, in the first class the string evolution is well behaved all the way up to the singularity, while in the second class it becomes ill-defined. Then assuming the singularities are regulated by string scale corrections, we consider the implications of the propagation through a “bounce.” It is known that as we evolve through a bounce, quantum strings will become excited giving rise to “particle transmutation.” We reconsider this effect, giving qualitative arguments for the amount of excitation for each class. We find that strings whose physical wavelength at the bounce is less than α' inevitably emerge in highly excited states, and that in this regime there is an interesting correspondence between strings on anisotropic cosmological spacetimes and plane waves. We argue that long wavelength modes, such as those describing cosmological perturbations, will also emerge in mildly excited string scale mass states. Finally we discuss the relevance of this to the propagation of cosmological perturbations in models such as the ekpyrotic/cyclic universe.

  4. THE 2H(alpha, gamma6LI REACTION AT LUNA AND BIG BANG NUCLEOSYNTHETIS

    Directory of Open Access Journals (Sweden)

    Carlo Gustavino

    2013-12-01

    Full Text Available The 2H(α, γ6Li reaction is the leading process for the production of 6Li in standard Big Bang Nucleosynthesis. Recent observations of lithium abundance in metal-poor halo stars suggest that there might be a 6Li plateau, similar to the well-known Spite plateau of 7Li. This calls for a re-investigation of the standard production channel for 6Li. As the 2H(α, γ6Li cross section drops steeply at low energy, it has never before been studied directly at Big Bang energies. For the first time the reaction has been studied directly at Big Bang energies at the LUNA accelerator. The preliminary data and their implications for Big Bang nucleosynthesis and the purported 6Li problem will be shown.

  5. Beyond Einstein: From the Big Bang to Black Holes

    Science.gov (United States)

    2005-01-01

    How did the Universe begin? Does time have a beginning and an end? Does space have edges? The questions are clear and simple. They are as old as human curiosity. But the answers have always seemed beyond the reach of science. Until now. In their attempts to understand how space, time, and matter are connected, Einstein and his successors made three predictions. First, space is expanding from a Big Bang; second, space and time can tie themselves into contorted knots called black holes where time actually comes to a halt; third, space itself contains some kind of energy that is pull- ing the Universe apart. Each of these three predictions seemed so fantastic when it was made that everyone, including Einstein himself, regarded them as unlikely. Incredibly, all three have turned out to be true. Yet Einstein's legacy is one of deep mystery, because his theories are silent on three questions raised by his fantastic predictions: (1) What powered the Big Bang? (2) What happens to space, time, and matter at the edge of a black hole? (3) What is the mysterious dark energy pulling the Universe apart? The answers to these questions-which lie at the crux of where our current theories fail us-will lead to a profound, new understanding of the nature of time and space. To find answers, however, we must venture beyond Einstein. The answers require new theories, such as the inflationary Universe and new insights in high-energy particle theory. Like Einstein s theories, these make fantastic predictions that seem hard to believe: unseen dimensions and entire universes beyond our own. We must find facts to confront and guide these new theories. Powerful new technologies now make this possible. And NASA and its partners are developing an armada of space-based observatories to chart the path to discovery. Here is where the Beyond Einstein story begins. By exploring the three questions that are Einstein s legacy, we begin the next revolution in understanding our Universe. We plot our way

  6. Classical propagation of strings across a big crunch/big bang singularity

    Science.gov (United States)

    Niz, Gustavo; Turok, Neil

    2007-01-01

    One of the simplest time-dependent solutions of M theory consists of nine-dimensional Euclidean space times 1+1-dimensional compactified Milne space-time. With a further modding out by Z2, the space-time represents two orbifold planes which collide and re-emerge, a process proposed as an explanation of the hot big bang [J. Khoury, B. A. Ovrut, P. J. Steinhardt, and N. Turok, Phys. Rev. D 64, 123522 (2001).PRVDAQ0556-282110.1103/PhysRevD.64.123522][P. J. Steinhardt and N. Turok, Science 296, 1436 (2002).SCIEAS0036-807510.1126/science.1070462][N. Turok, M. Perry, and P. J. Steinhardt, Phys. Rev. D 70, 106004 (2004).PRVDAQ0556-282110.1103/PhysRevD.70.106004]. When the two planes are near, the light states of the theory consist of winding M2-branes, describing fundamental strings in a particular ten-dimensional background. They suffer no blue-shift as the M theory dimension collapses, and their equations of motion are regular across the transition from big crunch to big bang. In this paper, we study the classical evolution of fundamental strings across the singularity in some detail. We also develop a simple semiclassical approximation to the quantum evolution which allows one to compute the quantum production of excitations on the string and implement it in a simplified example.

  7. Stilometrie en karakterisering in The Big Bang Theory

    Directory of Open Access Journals (Sweden)

    Maryka van Zyl

    2016-09-01

    Full Text Available Dialoog is ’n belangrike aspek van televisuele karakterkonstruering. Skrywers maak talige keuses namens die karakters en hierdie keuses kan daartoe aanleiding gee dat kykers ’n karakter met ’n spesifieke stereotipe subkultuur of sosiale groep vereenselwig. Hierdie studie ondersoek die talige konstruering van die karakter Sheldon Cooper in die CBS-sitkom The Big Bang Theory. ’n Trosanaliseboom van die spraak van elk van die vyf hoofkarakters in die eerste sewe seisoene (gegenereer deur die R-skrip Stylo 0.6.0 dui daarop dat die karakter Sheldon Cooper van die ander hoofkarakters (Leonard, Penny, Howard en Rajesh verskil ten opsigte van taalstyl. Hierdie verskille word verder ondersoek deur gebruik te maak van die korpusanalise program (WordSmith 6.0. om sleutelwoorde en leksikale bondels te identifiseer en om die gebruik van aktiewe en passiewe werkwoordkonstruksies te vergelyk. Sheldon se keuse van wetenskaplike of meer formele woorde en sy relatiewe voorkeur vir die passiefkonstruksie tipeer sy taalstyl as verduidelikend eerder as tipies van omgangstaal.

  8. The big bang? An eventful year in workers' compensation.

    Science.gov (United States)

    Guidotti, Tee L

    2006-01-01

    Workers' compensation in the past two years has been dominated by events in California, which have been so fundamental as to merit the term big bang. Passage of Senate Bill 899 has led to a comprehensive program of reform in access to medical care, access to rehabilitation services, temporary and permanent disability, evidence-based management, dispute resolution, and system innovation. Two noteworthy developments thus arose: a new requirement for apportionment by cause in causation analysis, and the adoption of evidence-based criteria for impairment assessment, treatment guidelines, and, soon, utilization review. Elsewhere in the United States, changes were modest, but extensive legislative activity in Texas suggests that Texas will be next to make major changes. In Canada, the Workers' Compensation Board of British Columbia has adopted an ambitious strategic initiative, and there is a Canadawide movement to establish presumption for certain diseases in firefighters. Suggestions for future directions include an increased emphasis on prevention, integration of programs, worker participation, enhancing the expertise of health care professionals, evidence-based management, process evaluation, and opportunities for innovation.

  9. Gravitationally induced adiabatic particle production: from big bang to de Sitter

    Science.gov (United States)

    de Haro, Jaume; Pan, Supriya

    2016-08-01

    In the background of a flat homogeneous and isotropic space-time, we consider a scenario of the Universe driven by the gravitationally induced ‘adiabatic’ particle production with constant creation rate. We have shown that this Universe attains a big bang singularity in the past and at late-time it asymptotically becomes de Sitter. To clarify this model Universe, we performed a dynamical analysis and found that the Universe attains a thermodynamic equilibrium in this late de Sitter phase. Finally, for the first time, we have discussed the possible effects of ‘adiabatic’ particle creations in the context of loop quantum cosmology.

  10. Revisiting big-bang nucleosynthesis constraints on dark-matter annihilation

    Directory of Open Access Journals (Sweden)

    Masahiro Kawasaki

    2015-12-01

    Full Text Available We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of anti-nucleons emitted by the annihilation of dark matter and the interconversion reactions of neutron and proton at inelastic scatterings of energetic nucleons. Comparing the theoretical prediction of the primordial light-element abundances with the latest observational constraints, we derive upper bounds on the dark-matter pair-annihilation cross section. Implication to some of particle-physics models are also discussed.

  11. The Theological Basis of Big Bang Cosmology and the Failure of General Relativity

    Science.gov (United States)

    Crothers, Stephen J.

    2013-09-01

    It is shown in this paper that the Big Bang Cosmology has its basis in theology, not in science, that it pertains to a Universe entirely filled by a single spherically symmetric continuous indivisible homogeneous body and therefore models nothing, that it violates the physical principles of General Relativity, that it violates the conservation of energy, and that General Relativity itself violates the usual conservation of energy and momentum and is therefore in conflict with experiment on a deep level, rendering Einstein's conception of the physical Universe and the gravitational field invalid.

  12. Revisiting big-bang nucleosynthesis constraints on dark-matter annihilation

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Masahiro [Institute for Cosmic Ray Research, The University of Tokyo, Kashiwa 277-8582 (Japan); Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa 277-8583 (Japan); Kohri, Kazunori [Theory Center, IPNS, KEK, Tsukuba 305-0801 (Japan); Sokendai, Tsukuba 305-0801 (Japan); Moroi, Takeo [Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa 277-8583 (Japan); Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Takaesu, Yoshitaro, E-mail: takaesu@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan)

    2015-12-17

    We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of anti-nucleons emitted by the annihilation of dark matter and the interconversion reactions of neutron and proton at inelastic scatterings of energetic nucleons. Comparing the theoretical prediction of the primordial light-element abundances with the latest observational constraints, we derive upper bounds on the dark-matter pair-annihilation cross section. Implication to some of particle-physics models are also discussed.

  13. Revisiting big-bang nucleosynthesis constraints on dark-matter annihilation

    Science.gov (United States)

    Kawasaki, Masahiro; Kohri, Kazunori; Moroi, Takeo; Takaesu, Yoshitaro

    2015-12-01

    We study the effects of dark-matter annihilation during the epoch of big-bang nucleosynthesis on the primordial abundances of light elements. We improve the calculation of the light-element abundances by taking into account the effects of anti-nucleons emitted by the annihilation of dark matter and the interconversion reactions of neutron and proton at inelastic scatterings of energetic nucleons. Comparing the theoretical prediction of the primordial light-element abundances with the latest observational constraints, we derive upper bounds on the dark-matter pair-annihilation cross section. Implication to some of particle-physics models are also discussed.

  14. Gamma rays and the case for baryon symmetric big-bang cosmology

    Science.gov (United States)

    Stecker, F. W.

    1977-01-01

    The baryon symmetric big-bang cosmologies offer an explanation of the present photon-baryon ratio in the universe, the best present explanation of the diffuse gamma-ray background spectrum in the 1 to 200 MeV range, and a mechanism for galaxy formation. In the context of an open universe model, the value of omega which best fits the present gamma-ray data is omega equals approx. 0.1 which does not conflict with upper limits on Comptonization distortion of the 3K background radiation. In regard to He production, evidence is discussed that nucleosynthesis of He may have taken place after the galaxies were formed.

  15. Deep mixing of 3He: reconciling Big Bang and stellar nucleosynthesis.

    Science.gov (United States)

    Eggleton, Peter P; Dearborn, David S P; Lattanzio, John C

    2006-12-08

    Low-mass stars, approximately 1 to 2 solar masses, near the Main Sequence are efficient at producing the helium isotope 3He, which they mix into the convective envelope on the giant branch and should distribute into the Galaxy by way of envelope loss. This process is so efficient that it is difficult to reconcile the low observed cosmic abundance of 3He with the predictions of both stellar and Big Bang nucleosynthesis. Here we find, by modeling a red giant with a fully three-dimensional hydrodynamic code and a full nucleosynthetic network, that mixing arises in the supposedly stable and radiative zone between the hydrogen-burning shell and the base of the convective envelope. This mixing is due to Rayleigh-Taylor instability within a zone just above the hydrogen-burning shell, where a nuclear reaction lowers the mean molecular weight slightly. Thus, we are able to remove the threat that 3He production in low-mass stars poses to the Big Bang nucleosynthesis of 3He.

  16. Measurements Of Stellar And Big-Bang Nucleosynthesis Reactions Using Inertially-Confined Plasmas

    Science.gov (United States)

    Zylstra, Alex; Herrmann, Hans; Gatu Johnson, Maria; Kim, Yongho; Frenje, Johan; Hale, Gerry; Li, Chikang; Rubery, Mike; Paris, Mark; Bacher, Andy; Brune, Carl; Forrest, Chad; Glebov, Vladimir; Janezic, Roger; McNabb, Dennis; Nikroo, Abbas; Pino, Jesse; Sangster, Craig; Seguin, Fredrick; Sio, Hong; Stoeckl, Christian; Petrasso, Richard

    2016-09-01

    The 3He+ 3He, T+3He, and p+D reactions directly relevant to either Stellar or Big-Bang Nucleosynthesis (BBN) have been studied at the OMEGA laser facility using inertially-confined plasmas, created using shock-driven `exploding pusher' implosions. These plasmas better mimic astrophysical systems than cold-target accelerator experiments. A new measured S-factor for the T(3He, γ)6Li reaction rules out an anomalously-high 6Li production during the Big Bang as an explanation to the high observed values in metal poor first generation stars. Our value is also inconsistent with values used in previous BBN calculations. Proton spectra from the 3He+3He and T+3He reactions are used to constrain nuclear R-matrix modeling, and recent experiments have probed the p+D reaction for the first time in a plasma. This work was partially supported by the LDRD program at LANL, US DOE, NLUF, LLE, and GA.

  17. Molecular evolution of colorectal cancer: from multistep carcinogenesis to the big bang.

    Science.gov (United States)

    Amaro, Adriana; Chiara, Silvana; Pfeffer, Ulrich

    2016-03-01

    Colorectal cancer is characterized by exquisite genomic instability either in the form of microsatellite instability or chromosomal instability. Microsatellite instability is the result of mutation of mismatch repair genes or their silencing through promoter methylation as a consequence of the CpG island methylator phenotype. The molecular causes of chromosomal instability are less well characterized. Genomic instability and field cancerization lead to a high degree of intratumoral heterogeneity and determine the formation of cancer stem cells and epithelial-mesenchymal transition mediated by the TGF-β and APC pathways. Recent analyses using integrated genomics reveal different phases of colorectal cancer evolution. An initial phase of genomic instability that yields many clones with different mutations (big bang) is followed by an important, previously not detected phase of cancer evolution that consists in the stabilization of several clones and a relatively flat outgrowth. The big bang model can best explain the coexistence of several stable clones and is compatible with the fact that the analysis of the bulk of the primary tumor yields prognostic information.

  18. Out of the White Hole: A Holographic Origin for the Big Bang

    CERN Document Server

    Pourhasan, Razieh; Mann, Robert B

    2013-01-01

    While most of the singularities of General Relativity are expected to be safely hidden behind event horizons by the cosmic censorship conjecture, we happen to live in the causal future of the classical big bang singularity, whose resolution constitutes the active field of early universe cosmology. Could the big bang be also hidden behind a causal horizon, making us immune to the decadent impacts of a naked singularity? We describe a braneworld description of cosmology with both 4d induced and 5d bulk gravity (otherwise known as Dvali-Gabadadze-Porati, or DGP model), which exhibits this feature: The universe emerges as a spherical 3-brane out of the formation of a 5d Schwarzschild black hole. In particular, we show that a pressure singularity of the holographic fluid, discovered earlier, happens inside the white hole horizon, and thus need not be real or imply any pathology. Furthermore, we outline a novel mechanism through which any thermal atmosphere for the brane, with comoving temperature of 20% of the 5D ...

  19. Review of Big Bang Nucleosynthesis and Primordial Abundances

    Science.gov (United States)

    Tytler, David; O'Meara, John M.; Suzuki, Nao; Lubin, Dan

    2001-03-01

    Big Bang Nucleosynthesis (BBN) is the synthesis of the light nuclei, Deuterium (D or 2H), 3He, 4He and 7Li during the first few minutes of the universe. This review concentrates on recent improvements in the measurement of the primordial (after BBN, and prior to modification) abundances of these nuclei. We mention improvement in the standard theory, and the non-standard extensions which are limited by the data. We have achieved an order of magnitude improvement in the precision of the measurement of primordial D/H, using the HIRES spectrograph on the W. M. Keck telescope to measure D in gas with very nearly primordial abundances towards quasars. From 1994 - 1996, it appeared that there could be a factor of ten range in primordial D/H, but today four examples of low D are secure. High D/H should be much easier to detect, and since there are no convincing examples, it must be extremely rare or non-existent. All data are consistent with a single low value for D/H, and the examples which are consistent with high D/H are readily interpreted as H contamination near the position of D. The new D/H measurements give the most accurate value for the baryon to photon ratio, η, and hence the cosmological baryon density. A similar density is required to explain the amount of Lyα absorption from neutral Hydrogen in the intergalactic medium (IGM) at redshift z ≃ 3, and to explain the fraction of baryons in local clusters of galaxies. The D/H measurements lead to predictions for the abundances of the other light nuclei, which generally agree with measurements. The remaining differences with some measurements can be explained by a combination of measurement and analysis errors or changes in the abundances after BBN. The measurements do not require physics beyond the standard BBN model. Instead, the agreement between the abundances is used to limit the non-standard physics. New measurements are giving improved understanding of the difficulties in estimating the abundances of all

  20. From Big Crunch to Big Bang with AdS/CFT

    CERN Document Server

    Turok, Neil; Hertog, Thomas

    2007-01-01

    The AdS/CFT correspondence is used to describe a five-dimensional cosmology with a big crunch singularity in terms of a super-Yang-Mills theory on $\\Rbar\\times S^3$ deformed by a potential which is unbounded below. Classically, a Higgs field in the dual theory rolls to infinity in finite time. But since the $S^3$ is finite, the unstable mode spreads quantum mechanically and the singularity is resolved when self-adjoint boundary conditions are imposed at infinity. Asymptotic freedom of the coupling governing the instability gives us computational control and the quantum spreading provides a UV cutoff on particle creation. The bulk translation of our result is a quantum transition from a big crunch to a big bang. An intriguing consequence of the near scale-invariance of the dual theory is that a nearly scale-invariant spectrum of stress-energy perturbations is automatically generated in the boundary theory. We comment on implications for more realistic cosmologies.

  1. No ``explosion'' in Big Bang cosmology: teaching kids the truth of what cosmologists really know

    Science.gov (United States)

    Gangui, Alejandro

    2011-06-01

    Common wisdom says that cosmologists are smart: they have developed a theory that can explain the ``origin of the universe''. Every time an astro-related, heavily funded ``big-science'' project comes to the media, naturally the question arises: will science -through this or that experiment- explain the origin of the cosmos? Can this be done with the LHC, for example? Will this dream machine create other universes? Of course, the very words we employ in cosmology reinforce this misconception: so Big Bang must be associated with an ``explosion'', even if a ``peculiar'' one, as it took place nowhere (there was presumably no space before the beginning) and happened virtually in no time (supposedly, space-time was created on this peculiar -singular- event). Right, the issue sounds confusing. Let us imagine what kids may get out of all this. We have recently presented a series of brief astronomy and cosmology books aimed at helping both kids and their teachers in these and other arcane subjects, all introduced with carefully chosen words and images that young children can understand. In particular, Volume Four deals with the Big Bang and emphasizes the notion of ``evolution'' as opposed to the -wrong- notion of ``origin'' behind the scientific model. We then explain some of the pillars of Big Bang cosmology: the expansion of space that drags away distant galaxies, as seen in the redshift of their emitted light; the build-up of light elements in a cooling bath of radiation, as explained by primordial nucleosynthesis; and the existence and main features of the ubiquitous cosmic microwave background radiation, where theory and observations agree to a highly satisfactory degree. Of course, one cannot attempt to answer the ``origins'' question when it is well known that all theories so far break down close to this origin (if there was actually an origin). It is through observations, analyses, lively discussions and recognition of the basic limitations of current theories and

  2. Time, space, stars and man the story of the Big Bang

    CERN Document Server

    Woolfson, Michael M

    2009-01-01

    Most well-read, but non-scientific, people will have heard of the term "Big Bang" as a description of the origin of the Universe. They will recognize that DNA identifies individuals and will know that the origin of life is one of the great unsolved scientific mysteries. This book brings together all of that material. Starting with the creation of space and time - known as the Big Bang - the book traces causally related steps through the formation of matter, of stars and planets, the Earth itself, the evolution of the Earth's surface and atmosphere, and then through to the beginnings of life an

  3. An Analysis of Verbal Humor in American Sitcom The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    吴珍; 芮艳芳

    2015-01-01

    Humor plays an indispensable part in human communication. This thesis is a tentative analysis of verbal humor under-standing within the framework of Relevance Theory. This paper, using The Big Bang Theory as a corpus, analyzes the humor gener-ated in the cognitive process of searching for relevance. According to the Relevance Theory, the understanding of humor is a pro-cess in which the hearer finds"relevance"in what seems"irrelevant". The author hopes that this analysis can help more people un-derstand and appreciate the humor in The Big Bang Theory. And meanwhile their personal sense of humor can also be improved.

  4. El concepto de big bang como inicio del proceso creativo del dibujo

    Directory of Open Access Journals (Sweden)

    Manuel Bru Serrano

    2015-01-01

    Full Text Available Este artículo establece un paralelismo entre la teoría del big bang y el comienzo de elaboración de un dibujo. Pretende sintetizar una serie de planteamientos de artistas, teóricos del arte y los experimentados a través del dibujo gracias a una propuesta artística personal. Unos trabajos, expuestos como un ejemplo de proceso creativo basado en el big bang, que muestran cómo los nuevos parámetros del dibujo contemporáneo ofrecen al artista numerosas posibilidades para enfocar la investigación artística.

  5. On Subtitle Translation of Sitcoms-A Case Study of The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    杨雯婷

    2013-01-01

    As we all know that exquisite subtitle translation of foreign film and television series is the fatal elements for them to spread among Chinese audiences. This article is based on Eugene·Nida’s“the Functional Equivalence”principle with three char⁃acteristics of sitcoms’subtitle to study the type, form and features of the Big Bang Theory, which lead to the conclusion of sitcom subtitle’s characteristics. It helps us to analyze its subtitle from six aspects. As the result, the author of the paper makes the conclu⁃sion of translation tactic about Big Bang Theory, which could help the subtitle translation of similar sitcoms.

  6. The Big Bang and the Search for a Theory of Everything

    Science.gov (United States)

    Kogut, Alan

    2010-01-01

    How did the universe begin? Is the gravitational physics that governs the shape and evolution of the cosmos connected in a fundamental way to the sub-atomic physics of particle colliders? Light from the Big Bang still permeates the universe and carries within it faint clues to the physics at the start of space and time. I will describe how current and planned measurements of the cosmic microwave background will observe the Big Bang to provide new insight into a "Theory of Everything" uniting the physics of the very large with the physics of the very small.

  7. El concepto de big bang como inicio del proceso creativo del dibujo

    OpenAIRE

    2015-01-01

    Este artículo establece un paralelismo entre la teoría del big bang y el comienzo de elaboración de un dibujo. Pretende sintetizar una serie de planteamientos de artistas, teóricos del arte y los experimentados a través del dibujo gracias a una propuesta artística personal. Unos trabajos, expuestos como un ejemplo de proceso creativo basado en el big bang, que muestran cómo los nuevos parámetros del dibujo contemporáneo ofrecen al artista numerosas posibilidades para enfocar la investigación ...

  8. Detection of Pristine Gas Two Billion Years after the Big Bang

    CERN Document Server

    Fumagalli, Michele; Prochaska, J Xavier

    2011-01-01

    In the current cosmological model, only the three lightest elements were created in the first few minutes after the Big Bang; all other elements were produced later in stars. To date, however, heavy elements have been observed in all astrophysical environments. We report the detection of two gas clouds with no discernible elements heavier than hydrogen. These systems exhibit the lowest heavy-element abundance in the early universe and thus are potential fuel for the most metal poor halo stars. The detection of deuterium in one system at the level predicted by primordial nucleosynthesis provides a direct confirmation of the standard cosmological model. The composition of these clouds further implies that the transport of heavy elements from galaxies to their surroundings is highly inhomogeneous.

  9. Detection of pristine gas two billion years after the Big Bang.

    Science.gov (United States)

    Fumagalli, Michele; O'Meara, John M; Prochaska, J Xavier

    2011-12-02

    In the current cosmological model, only the three lightest elements were created in the first few minutes after the Big Bang; all other elements were produced later in stars. To date, however, heavy elements have been observed in all astrophysical environments. We report the detection of two gas clouds with no discernible elements heavier than hydrogen. These systems exhibit the lowest heavy-element abundance in the early universe, and thus are potential fuel for the most metal-poor halo stars. The detection of deuterium in one system at the level predicted by primordial nucleosynthesis provides a direct confirmation of the standard cosmological model. The composition of these clouds further implies that the transport of heavy elements from galaxies to their surroundings is highly inhomogeneous.

  10. Pre-Big Bang, space-time structure, asymptotic Universe

    Directory of Open Access Journals (Sweden)

    Gonzalez-Mestres Luis

    2014-04-01

    Full Text Available Planck and other recent data in Cosmology and Particle Physics can open the way to controversial analyses concerning the early Universe and its possible ultimate origin. Alternatives to standard cosmology include pre-Big Bang approaches, new space-time geometries and new ultimate constituents of matter. Basic issues related to a possible new cosmology along these lines clearly deserve further exploration. The Planck collaboration reports an age of the Universe t close to 13.8 Gyr and a present ratio H between relative speeds and distances at cosmic scale around 67.3 km/s/Mpc. The product of these two measured quantities is then slightly below 1 (about 0.95, while it can be exactly 1 in the absence of matter and cosmological constant in patterns based on the spinorial space-time we have considered in previous papers. In this description of space-time we first suggested in 1996-97, the cosmic time t is given by the modulus of a SU(2 spinor and the Lundmark-Lemaître-Hubble (LLH expansion law turns out to be of purely geometric origin previous to any introduction of standard matter and relativity. Such a fundamental geometry, inspired by the role of half-integer spin in Particle Physics, may reflect an equilibrium between the dynamics of the ultimate constituents of matter and the deep structure of space and time. Taking into account the observed cosmic acceleration, the present situation suggests that the value of 1 can be a natural asymptotic limit for the product H t in the long-term evolution of our Universe up to possible small corrections. In the presence of a spinorial space-time geometry, no ad hoc combination of dark matter and dark energy would in any case be needed to get an acceptable value of H and an evolution of the Universe compatible with observation. The use of a spinorial space-time naturally leads to unconventional properties for the space curvature term in Friedmann-like equations. It therefore suggests a major modification of

  11. Sneutrino condensate as a candidate for the hot big bang cosmology

    CERN Document Server

    Mazumdar, A; Mazumdar, Anupam

    2004-01-01

    If inflationary paradigm is correct, then it must create conditions for the hot big bang model with all observed matter, baryons and seed perturbations for the structure formation. In this paper we propose a scenario where the inflaton energy density is dumped into the bulk in a brane world setup, and all the required physical conditions are created by the right handed neutrino sector within supersymmetry. The scalar component of the right handed Majorana neutrino is responsible for generating the scale invariant fluctuations in the cosmic microwave background radiation, reheating the Universe at a temperature $T_{rh}\\leq 10^{9}$ GeV, and finally generating the lepton asymmetry, $n_{B}/s\\sim 10^{-10}$.

  12. Low-lying Resonances and Relativistic Screening in Big Bang Nucleosynthesis

    CERN Document Server

    Famiano, Michael A; Kajino, Toshitaka

    2016-01-01

    We explore effects of the screening due to the relativistic electron-positron plasma and presence of resonances in the secondary reactions leading to A=7 nuclei during the Big Bang Nucleosynthesis. In particular, we investigate and examine possible low-lying resonances in the 7Be(3He, g)10C reaction and examine the resultant destruction of 7Be for various resonance locations and strengths. While a resonance in the 10C compound nucleus is thought to have negligible effects we explore the possibility of an enhancement from plasma screening that may adjust the final 7Be abundance. We find the effects of relativistic screening and possible low-lying resonances to be relatively small in the standard Early Universe models.

  13. Challenges in Cosmology from the Big Bang to Dark Energy, Dark Matter and Galaxy Formation

    CERN Document Server

    Silk, Joseph

    2016-01-01

    I review the current status of Big Bang Cosmology, with emphasis on current issues in dark matter, dark energy, and galaxy formation. These topics motivate many of the current goals of experimental cosmology which range from targeting the nature of dark energy and dark matter to probing the epoch of the first stars and galaxies.

  14. In search of the big bang the life and the death of the universe

    CERN Document Server

    Gribbin, John

    1998-01-01

    Where do we come from? How did the universe of stars, planets and people come into existence? Now revised and expanded, this second edition takes into account developments in cosmology and quantum physics since its first publication in 1986, and traces the historical path which has led physicists to an understanding of the big bang, the fireball in which our universe was born.

  15. After the Big Bang: What's Next in Design Education? Time to Relax?

    Science.gov (United States)

    Fleischmann, Katja

    2015-01-01

    The article "Big Bang technology: What's next in design education, radical innovation or incremental change?" (Fleischmann, 2013) appeared in the "Journal of Learning Design" Volume 6, Issue 3 in 2013. Two years on, Associate Professor Fleischmann reflects upon her original article within this article. Although it has only been…

  16. Initial conditions and the structure of the singularity in pre-big-bang cosmology

    NARCIS (Netherlands)

    Feinstein, A.; Kunze, K.E.; Vazquez-Mozo, M.A.

    2000-01-01

    We propose a picture, within the pre-big-bang approach, in which the universe emerges from a bath of plane gravitational and dilatonic waves. The waves interact gravitationally breaking the exact plane symmetry and lead generically to gravitational collapse resulting in a singularity with the Kasner

  17. From the Big Bang to the Nobel Prize and on to the James Webb Space Telescope

    Science.gov (United States)

    Mather, John C.

    2008-01-01

    The history of the universe in a nutshell, from the Big Bang to now. and on to the future - John Mather will tell the story of how we got here, how the Universe began with a Big Bang, how it could have produced an Earth where sentient beings can live, and how those beings are discovering their history. Mather was Project Scientist for NASA's Cosmic Background Explorer (COBE) satellite, which measured the spectrum (the color) of the heat radiation from the Big Bang, discovered hot and cold spots in that radiation, and hunted for the first objects that formed after the great explosion. He will explain Einstein's biggest mistake, show how Edwin Hubble discovered the expansion of the univerre, how the COBE mission was built, and how the COBE data support the Big Bang theory. He will also show NASA's plans for the next great telescope in space, the Jarnes Webb Space Telescope. It will look even farther back in time than the Hubble Space Telescope, and will look inside the dusty cocoons where rtars and planets are being born today. Planned for launch in 2013, it may lead to another Nobel Prize for some lucky observer.

  18. From the Big Bang to the Nobel Prize and on to James Webb Space Telescope

    Science.gov (United States)

    Mather, John C.

    2009-01-01

    The history of the universe in a nutshell, from the Big Bang to now, and on to the future - John Mather will tell the story of how we got here, how the Universe began with a Big Bang, how it could have produced an Earth where sentient beings can live, and how those beings are discovering their history. Mather was Project Scientist for NASA s Cosmic Background Explorer (COBE) satellite, which measured the spectrum (the color) of the heat radiation from the Big Bang, discovered hot and cold spots in that radiation, and hunted for the first objects that formed after the great explosion. He will explain Einstein s biggest mistake, show how Edwin Hubble discovered the expansion of the universe, how the COBE mission was built, and how the COBE data support the Big Bang theory. He will also show NASA s plans for the next great telescope in space, the James Webb Space Telescope. It will look even farther back in time than the Hubble Space Telescope, and will look inside the dusty cocoons where stars and planets are being born today. Planned for launch in 2013, it may lead to another Nobel Prize for some lucky observer.

  19. Big Bang Nucleosynthesis in the presence of sterile neutrinos with altered dispersion relations

    CERN Document Server

    Aeikens, Elke; Pakvasa, Sandip; Weiler, Thomas J

    2016-01-01

    Big Bang Nucleosynthesis imposes stringent bounds on light sterile neutrinos mixing with the active flavors. Here we discuss how altered dispersion relations can weaken such bounds and allow compatibility of new sterile neutrino degrees of freedom with a successful generation of the light elements in the early Universe.

  20. From the big bang to the eureka moment

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, Peter

    2002-02-01

    A Brief History of Time made Stephen Hawking famous, but he was already a world leader in cosmology. Peter Rodgers reports from the celebrations to mark Hawking's 60th birthday. Masters of the universe Stephen Hawking is the most famous physicist in the world. Indeed, the sales of Hawking's books and his appearances on The Simpsons and Star Trek have tended to overshadow his scientific achievements. But that was not the case in Cambridge last month when Hawking's contributions to physics and cosmology were celebrated at a week-long conference to mark his 60th birthday. 'We organized the meeting to look back on the immense contribution that Stephen has made to many areas of gravitational physics and cosmology,' said Gary Gibbons, one of Hawking's colleagues at Cambridge. 'We also wanted to look forward to what the future might hold for theoretical physics and cosmology, with special reference to the areas that Stephen has been most interested and most active in.' Hawking made his name with a series of papers in the 1960s on singularities in cosmology. Building on work by Roger Penrose, he showed that Einstein's general theory of relativity implied that space and time would have a beginning in the big bang and would end in a singularity. 'How unlike particle physics, where people were falling over themselves to latch onto the latest idea. They still are.' Hawking then switched his attention to black holes - regions of space where gravity is so strong that nothing can escape. He was also one of the first physicists to make progress in combining general relativity - the classical theory of gravity - and quantum mechanics. First he showed that when two black holes collide and merge, the area of the 'event horizon' around the resulting black hole is greater than the sum of the two original areas. This led Hawking and co-workers to link the area of the event horizon, A, with the entropy of a black hole, S

  1. Leadership in the Big Bangs of European Integration

    DEFF Research Database (Denmark)

    types of circumstances, and who provides leadership affects the shape of the final outcome. The use of a common framework throughout allows the volume to provide some tentative answers to the following empirical questions: which actors have driven the European integration process in the last two decades...... bangs in the European integration process in the past two decades, and why.  ......European Union constitutional negotiations are very complex, unpredictable and messy affairs with high bargaining (transaction) costs. Leadership is often necessary in order for the parties to find and agree upon a mutually acceptable outcome. Various types of leadership are demanded in different...

  2. Constraints on unparticle long range forces from big bang nucleosynthesis bounds on the variation of the gravitational coupling

    OpenAIRE

    2009-01-01

    We use big bang nucleosynthesis bounds on the variation of the gravitational coupling to derive constraints on the strength of the deviation from the gravitational inverse-square law due to tensor and vector unparticle exchange.

  3. Gigantic particle collision machine does "mini Big Bangs"

    CERN Multimedia

    2007-01-01

    "The world's largest machine is reputed to be the Large Hadron Collider (LHC) at CERN in Geneva and everything about it is big. Designed to carry out high energy particle collisions, when completed next year, one of the collider's experiments includes a 10'000 ton detector." (1/2 page)

  4. Time, space, stars and man the story of the Big Bang

    CERN Document Server

    Woolfson, Michael M

    2013-01-01

    The three greatest scientific mysteries, which remain poorly understood, are the origin of the universe, the origin of life and the development of consciousness. This book describes the processes preceding the Big Bang, the creation of matter, the concentration of that matter into stars and planets, the development of simple life forms and the theory of evolution that has given higher life forms, including mankind. Readership: Members of the general public who have an interest in popular science. There are many popular and excellent science books that present various aspects of science. However, this book follows a narrow scientific pathway from the Big Bang to mankind, and depicts the causal relationship between each step and the next. The science covered will be enough to satisfy most readers. Many important areas of science are dealt with, and these include cosmology, particle physics, atomic physics, galaxy and star formation, planet formation and aspects of evolution. The necessary science is described i...

  5. Effects of variation of fundamental constants from Big Bang to atomic clocks

    Science.gov (United States)

    Flambaum, Victor

    2004-05-01

    Theories unifying gravity with other interactions suggest temporal and spatial variation of the fundamental "constants" in expanding Universe. I discuss effects of variation of the fine structure constant, strong interaction, quark mass and gravitational constant. The measurements of these variations cover the lifespan of the Universe from few minutes after Big Bang to the present time and give controversial results. There are some hints for the variations in Big Bang nucleosynthesis, quasar absorption spectra and Oklo natural nuclear reactor data. A very promising method to search for the variation of the fundamental constants consists in comparison of different atomic clocks. A billion times enhancement of the variation effects happens in transitions between accidentally degenerate atomic energy levels.

  6. Le big bang n'est pas une théorie comme les autres

    CERN Document Server

    Bonnet-Bidaud, Jean-Marc; Leglu, Dominique; Reinisch, Gilbert

    2009-01-01

    Le big bang n'est pas une théorie comme les autres. Ce n'est d'ailleurs pas une théorie physique au sens propre du terme, mais un scénario cosmologique issu des équations de la relativité générale. Il est le modèle qui s'ajuste le mieux aux observations actuelles, mais à quel prix ? Il nous livre un Univers composé à 96 % de matière et d'énergie noires inconnues. C'est donc un euphémisme que de dire que le big bang semble poser autant - sinon plus - de questions qu'il n'en résout. En ce sens, le big bang apparaît davantage comme une paramétrisation de notre ignorance plutôt que comme une modélisation d'un phénomène. Pourtant, le succès du big bang et l'adhésion qu'il suscite, tant dans la sphère scientifique que dans la sphère médiatique, ne se démentent pas. Surmédiatisé, son statut dépasse celui de modèle théorique, et la simple évocation de son nom suffit pour justifier des opérations de marketing scientifique ou rejeter des cosmologies alternatives. Pour éclaircir les pr...

  7. The moment of creation big bang physics from before the first millisecond to the present universe

    CERN Document Server

    Trefil, James S

    2004-01-01

    ""Trefil surpasses almost all other scientists writing about science"" "- The New York Times""Fascinating reading. A mind-stretching book."" - John Barkham ReviewsCompelling and lucid, this reader-friendly narrative travels billions of years back in time to depict the events that culminated in the Big Bang: the colossal explosion that initiated the existence of the universe. James Trefil is one of the founders of modern quark theory, and he specializes in explaining complex scientific matters to nonspecialists.

  8. Analysis of Humor in The Big Bang Theory Based on the Conversational Relevance

    Institute of Scientific and Technical Information of China (English)

    XU Yang

    2014-01-01

    Humor is the life buoy in waves of life. Pragmatics and humor are closely linked. Relevance is one of the important topics of Pragmatics. This paper takes the lines from The Big Bang Theory as a case study and analyzes the humorous effect from the perspective of Principle of Relevance and Conversational Relevance, hoping to help people deepen the appreciation and un⁃derstanding of humor.

  9. Gamma-rays and the case for baryon symmetric big-bang cosmology

    Science.gov (United States)

    Stecker, F. W.

    1977-01-01

    The baryon symmetric big-bang cosmologies offer an explanation of the present photon-baryon ratio in the universe, the best present explanation of the diffuse gamma-ray background spectrum in the 1-200 MeV range, and a mechanism for galaxy formation. In regard to He production, evidence is discussed that nucleosynthesis of He may have taken place after the galaxies were formed.

  10. Calixarenes and cations: a time-lapse photography of the big-bang.

    Science.gov (United States)

    Casnati, Alessandro

    2013-08-07

    The outstanding cation complexation properties emerging from the pioneering studies on calixarene ligands during a five-year period in the early 1980s triggered a big-bang burst of publications on such macrocycles that is still lasting at a distance of more than 30 years. A time-lapse photography of this timeframe is proposed which allows the readers to pinpoint the contributions of the different research groups.

  11. The Passport to the Big Bang: a trail of discovery of CERN and its sites

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    Sunday 2 June 2013 will see the launch of CERN’s Passport to the Big Bang, a scientific tourist trail linking ten of the Laboratory’s sites in the Pays de Gex and the Canton of Geneva. CERN is organising a public event to celebrate the launch and needs lots of volunteers – you could be one of them!   The exhibition platform in Sergy, in front of the ALICE experiment. Does your grocer insist that the Pays de Gex is going to be swallowed up by a black hole made by the LHC? Do your neighbours ask you questions about the CERN site visible from your houses, leaving you stumped when you don’t have the answers?  Well then, take them on an accelerator tour – but above ground and with no need for access cards! How? By taking advantage of the Passport to the Big Bang, a cross-border scientific tourist trail that will be inaugurated on 2 June. The goal of the Passport to the Big Bang is provide the local population wi...

  12. Big Bang Bifurcation Analysis and Allee Effect in Generic Growth Functions

    Science.gov (United States)

    Leonel Rocha, J.; Taha, Abdel-Kaddous; Fournier-Prunaret, D.

    2016-06-01

    The main purpose of this work is to study the dynamics and bifurcation properties of generic growth functions, which are defined by the population size functions of the generic growth equation. This family of unimodal maps naturally incorporates a principal focus of ecological and biological research: the Allee effect. The analysis of this kind of extinction phenomenon allows to identify a class of Allee’s functions and characterize the corresponding Allee’s effect region and Allee’s bifurcation curve. The bifurcation analysis is founded on the performance of fold and flip bifurcations. The dynamical behavior is rich with abundant complex bifurcation structures, the big bang bifurcations of the so-called “box-within-a-box” fractal type being the most outstanding. Moreover, these bifurcation cascades converge to different big bang bifurcation curves with distinct kinds of boxes, where for the corresponding parameter values several attractors are associated. To the best of our knowledge, these results represent an original contribution to clarify the big bang bifurcation analysis of continuous 1D maps.

  13. 总星系局爆宇宙理论%Theory of Local Big Bang of Metagalaxy on Universe

    Institute of Scientific and Technical Information of China (English)

    殷业; 胡素辉

    2013-01-01

    大爆炸宇宙理论是一个非常成功的宇宙理论,它在经过古斯等人提出的暴涨理论修正后日趋完善。但即使这样也还存在几个难题无法解决:(1)欧洲普朗克望远镜揭示的宇宙背景辐射的不对称性;(2)宇宙中所有物质来源于大爆炸没有实验依据;(3)存在暴涨中宇宙膨胀的超光速问题。为了解释上述难题,本文提出了一种建立在大爆炸宇宙理论基础上的多宇宙模型:总星系局爆宇宙模型。该模型可以很好地解决上述难题,文中提出了检验理论模型新的实验方法,通过实验可以最终确认真实的宇宙到底更符合哪个模型。%Big Bang Theory is a very successful theory of the Universe, which is maturing after being cor-rected by Alan Guth proposed inflation theory. But even so, there are several problems can’t be solved:(a) European Planck telescope reveals the cosmic background radiation asymmetry; (b) Big Bang created all matter in the Universe there isn’t experimental evidence; (c) superluminal in inflation theory is contra-diction with relativistic invariance of light speed assumption. In order to explain these problems, this pa-per presents a new model of the Universe based on the Big Bang Theory: Model of Local Big Bang of Metagalaxy. The model can be a good solution to these problems, it is also proposed an experimental methods of tested theoretical model, the experiment can finally confirm which model is more in line with the real Universe in the end.

  14. On the relation between boundary proposals and hidden symmetries of the extended pre-big bang quantum cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Jalalzadeh, S.; Rostami, T. [Shahid Beheshti University, Department of Physics, Tehran (Iran, Islamic Republic of); Moniz, P.V. [Centro de Matematica e Aplicacoes-UBI, Covilha (Portugal); Universidade da Beira Interior, Departamento de Fisica, Covilha (Portugal)

    2015-01-01

    A framework associating quantum cosmological boundary conditions to minisuperspace hidden symmetries has been introduced in Jalalzadeh and Moniz (Phys Rev D 89:083504, 2014). The scope of the application was, notwithstanding the novelty, restrictive because it lacked a discussion involving realistic matter fields. Therefore, in the present letter, we extend the framework scope to encompass elements from a scalar-tensor theory in the presence of a cosmological constant. More precisely, it is shown that hidden minisuperspace symmetries present in a pre-big bang model suggest a process from which boundary conditions can be selected. (orig.)

  15. A high abundance of massive galaxies 3-6 billion years after the Big Bang.

    Science.gov (United States)

    Glazebrook, Karl; Abraham, Roberto G; McCarthy, Patrick J; Savaglio, Sandra; Chen, Hsiao-Wen; Crampton, David; Murowinski, Rick; Jørgensen, Inger; Roth, Kathy; Hook, Isobel; Marzke, Ronald O; Carlberg, R G

    2004-07-08

    Hierarchical galaxy formation is the model whereby massive galaxies form from an assembly of smaller units. The most massive objects therefore form last. The model succeeds in describing the clustering of galaxies, but the evolutionary history of massive galaxies, as revealed by their visible stars and gas, is not accurately predicted. Near-infrared observations (which allow us to measure the stellar masses of high-redshift galaxies) and deep multi-colour images indicate that a large fraction of the stars in massive galaxies form in the first 5 Gyr (refs 4-7), but uncertainties remain owing to the lack of spectra to confirm the redshifts (which are estimated from the colours) and the role of obscuration by dust. Here we report the results of a spectroscopic redshift survey that probes the most massive and quiescent galaxies back to an era only 3 Gyr after the Big Bang. We find that at least two-thirds of massive galaxies have appeared since this era, but also that a significant fraction of them are already in place in the early Universe.

  16. The surprising influence of late charged current weak interactions on Big Bang Nucleosynthesis

    Science.gov (United States)

    Grohs, E.; Fuller, George M.

    2016-10-01

    The weak interaction charged current processes (νe + n ↔ p +e-; νbare + p ↔ n +e+; n ↔ p +e- +νbare) interconvert neutrons and protons in the early universe and have significant influence on Big Bang Nucleosynthesis (BBN) light-element abundance yields, particularly that for 4He. We demonstrate that the influence of these processes is still significant even when they operate well below temperatures T ∼ 0.7 MeV usually invoked for "weak freeze-out," and in fact down nearly into the alpha-particle formation epoch (T ≈ 0.1 MeV). This physics is correctly captured in commonly used BBN codes, though this late-time, low-temperature persistent effect of the isospin-changing weak processes, and the sensitivity of the associated rates to lepton energy distribution functions and blocking factors are not widely appreciated. We quantify this late-time influence by analyzing weak interaction rate dependence on the neutron lifetime, lepton energy distribution functions, entropy, the proton-neutron mass difference, and Hubble expansion rate. The effects we point out here render BBN a keen probe of any beyond-standard-model physics that alters lepton number/energy distributions, even subtly, in epochs of the early universe all the way down to near T = 100 keV.

  17. Implication of the proton-deuteron radiative capture for Big Bang Nucleosynthesis

    CERN Document Server

    Marcucci, L E; Kievsky, A; Viviani, M

    2015-01-01

    The astrophysical $S$-factor for the radiative capture $d(p,\\gamma)^3$He in the energy-range of interest for Big Bang Nucleosynthesis (BBN) is calculated using an {\\it ab-initio} approach. The nuclear Hamiltonian retains both two- and three-nucleon interactions - the Argonne $v_{18}$ and the Urbana IX, respectively. Both one- and many-body contributions to the nuclear current operator are included. The former retain for the first time, besides the $1/m$ leading order contribution ($m$ is the nucleon mass), also the next-to-leading order term, proportional to $1/m^3$. The many-body currents are constructed in order to satisfy the current conservation relation with the adopted Hamiltonian model. The hyperspherical harmonics technique is applied to solve the $A=3$ bound and scattering states. A particular attention is used in this second case in order to obtain, in the energy range of BBN, an uncertainty on the astrophysical $S$-factor of the order or below $\\sim$1 %. Then, in this energy range, the $S$-factor i...

  18. The ripples of "The Big (agricultural) Bang": the spread of early wheat cultivation.

    Science.gov (United States)

    Abbo, Shahal; Gopher, Avi; Peleg, Zvi; Saranga, Yehoshua; Fahima, Tzion; Salamini, Francesco; Lev-Yadun, Simcha

    2006-08-01

    Demographic expansion and (or) migrations leave their mark in the pattern of DNA polymorphisms of the respective populations. Likewise, the spread of cultural phenomena can be traced by dating archaeological finds and reconstructing their direction and pace. A similar course of events is likely to have taken place following the "Big Bang" of the agricultural spread in the Neolithic Near East from its core area in southeastern Turkey. Thus far, no attempts have been made to track the movement of the founder genetic stocks of the first crop plants from their core area based on the genetic structure of living plants. In this minireview, we re-interpret recent wheat DNA polymorphism data to detect the genetic ripples left by the early wave of advance of Neolithic wheat farming from its core area. This methodology may help to suggest a model charting the spread of the first farming phase prior to the emergence of truly domesticated wheat types (and other such crops), thereby increasing our resolution power in studying this revolutionary period of human cultural, demographic, and social evolution.

  19. Quantum Oscillations Can Prevent the Big Bang Singularity in an Einstein-Dirac Cosmology

    Science.gov (United States)

    Finster, Felix; Hainzl, Christian

    2010-01-01

    We consider a spatially homogeneous and isotropic system of Dirac particles coupled to classical gravity. The dust and radiation dominated closed Friedmann-Robertson-Walker space-times are recovered as limiting cases. We find a mechanism where quantum oscillations of the Dirac wave functions can prevent the formation of the big bang or big crunch singularity. Thus before the big crunch, the collapse of the universe is stopped by quantum effects and reversed to an expansion, so that the universe opens up entering a new era of classical behavior. Numerical examples of such space-times are given, and the dependence on various parameters is discussed. Generically, one has a collapse after a finite number of cycles. By fine-tuning the parameters we construct an example of a space-time which satisfies the dominant energy condition and is time-periodic, thus running through an infinite number of contraction and expansion cycles.

  20. Quantum Oscillations Prevent the Big Bang Singularity in an Einstein-Dirac Cosmology

    CERN Document Server

    Finster, Felix

    2008-01-01

    We consider a spatially homogeneous and isotropic system of Dirac particles coupled to classical gravity. The dust and radiation dominated closed Friedmann-Robertson-Walker space-times are recovered as limiting cases. We find a mechanism where quantum oscillations of the Dirac wave functions prevent the formation of the big bang or big crunch singularity. Thus before the big crunch, the collapse of the universe is stopped by quantum effects and reversed to an expansion, so that the universe opens up entering a new era of classical behavior. Numerical examples of such space-times are given, and the dependence on various parameters is discussed. We finally give an example of a space-time which satisfies the dominant energy condition and is time-periodic, thus running through an infinite number of contraction and expansion cycles.

  1. Where Are the Logical Errors in the Theory of Big Bang?

    Science.gov (United States)

    Kalanov, Temur Z.

    2015-04-01

    The critical analysis of the foundations of the theory of Big Bang is proposed. The unity of formal logic and of rational dialectics is methodological basis of the analysis. It is argued that the starting point of the theory of Big Bang contains three fundamental logical errors. The first error is the assumption that a macroscopic object (having qualitative determinacy) can have an arbitrarily small size and can be in the singular state (i.e., in the state that has no qualitative determinacy). This assumption implies that the transition, (macroscopic object having the qualitative determinacy) --> (singular state of matter that has no qualitative determinacy), leads to loss of information contained in the macroscopic object. The second error is the assumption that there are the void and the boundary between matter and void. But if such boundary existed, then it would mean that the void has dimensions and can be measured. The third error is the assumption that the singular state of matter can make a transition into the normal state without the existence of the program of qualitative and quantitative development of the matter, without controlling influence of other (independent) object. However, these assumptions conflict with the practice and, consequently, formal logic, rational dialectics, and cybernetics. Indeed, from the point of view of cybernetics, the transition, (singular state of the Universe) -->(normal state of the Universe),would be possible only in the case if there was the Managed Object that is outside the Universe and have full, complete, and detailed information about the Universe. Thus, the theory of Big Bang is a scientific fiction.

  2. Majorana Neutrino Magnetic Moment and Neutrino Decoupling in Big Bang Nucleosynthesis

    CERN Document Server

    Vassh, N; Balantekin, A B; Fuller, G M

    2015-01-01

    We examine the physics of the early universe when neutrinos (electron neutrino, muon neutrino, tau neutrino) possess transition magnetic moments. These extra couplings beyond the usual weak interaction couplings alter the way neutrinos decouple from the plasma of electrons/positrons and photons. We calculate how transition magnetic moment couplings modify neutrino decoupling temperatures, and then use a full weak, strong, and electromagnetic reaction network to compute corresponding changes in Big Bang Nucleosynthesis abundance yields. We find that light element observational constraints and other cosmological constraints may allow probes of neutrino transition magnetic moments which are not directly available in the laboratory.

  3. Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''

    CERN Document Server

    Matsuura, Shunji; Hashimoto, Masa-aki; Sato, Katsuhiko

    2007-01-01

    This is a reply report to astro-ph/0604264. We studied heavy element production in high baryon density region in early universe astro-ph/0507439. However it is claimed in astro-ph/0604264 that small scale but high baryon density region contradicts observations for the light element abundance or in order not to contradict to observations high density region must be so small that it cannot affect the present heavy element abundance. In this paper we study big bang nucleosynthesis in high baryon density region and show that in certain parameter spaces it is possible to produce enough amount of heavy element without contradiction to CMB and light element observations.

  4. Stable Emergent Universe -- A Creation without Big-Bang

    CERN Document Server

    Guendelman, Eduardo; Labrana, Pedro; Nissimov, Emil; Pacheva, Svetlana

    2015-01-01

    Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we derive an effective "Einstein-frame" theory featuring the following remarkable properties: (i) We obtain effective potential for the cosmological scalar field possessing two infinitely large flat regions which allows for a unified description of both early universe inflation as well as of present dark energy epoch; (ii) For a specific parameter range the model possesses a non-singular stable "emergent universe" solution which describes an initial phase of evolution that precedes the inflationary phase.

  5. Stable emergent Universe - a creation without Big-Bang

    Science.gov (United States)

    Guendelman, E.; Herrera, R.; Labrana, P.; Nissimov, E.; Pacheva, S.

    2015-11-01

    Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we derive an effective ``Einstein-frame'' theory featuring the following remarkable properties: (i) We obtain effective potential for the cosmological scalar field possessing two infinitely large flat regions which allows for a unified description of both early Universe inflation as well as of present dark energy epoch; (ii) for a specific parameter range the model possesses a non-singular stable ``emergent Universe'' solution which describes an initial phase of evolution that precedes the inflationary phase.

  6. Researchers Develop Method to Identify Sparticles in Big Bang Conditions

    CERN Multimedia

    2008-01-01

    Three Northeastern University researchers have proposed a new approach for the highly anticipated discovery of supersymmetric particles, often called sparticles. The methodology, which was published in the December 21 issue of the Physical Review Letters, is based on identifying the hierarchical mass patterns of sparticles, which are assumed to exist in a new class of particle physics theories beyond the Standard Model.

  7. The critical geometry of a thermal big bang

    CERN Document Server

    Afshordi, Niayesh

    2016-01-01

    We explore the space of scalar-tensor theories containing two disformally related metrics, and find a discontinuity pointing to a special "critical" cosmological solution. This solution has a simple geometrical interpretation based on the action of a probe 3-brane embedded in an $EAdS_2\\times E_3$ geometry. Due to the different maximal speeds of propagation for matter and gravity, the cosmological fluctuations start off inside the horizon even without inflation, and will more naturally have a thermal origin (since there is never vacuum domination). The critical model makes an unambiguous, non-tuned prediction for the spectral index of the scalar fluctuations left outside the horizon: $n_s= 0.96478(64)$. Adding to this that no gravitational waves are produced, we have unveiled the most predictive model on offer.

  8. Big Bang Nucleosynthesis in Visible and Hidden-Mirror Sectors

    Directory of Open Access Journals (Sweden)

    Paolo Ciarcelluti

    2014-01-01

    dark matter. The production of ordinary nuclides shows differences from the standard model for a ratio of the temperatures between mirror and ordinary sectors x=T′/T≳0.3, and they present an interesting decrease of the abundance of Li7. For the mirror nuclides, instead, one observes an enhanced production of He4, which becomes the dominant element for x≲0.5, and much larger abundances of heavier elements.

  9. A fairytale creation or the beginning of everything: Students’ pre-instructional conceptions about the Big Bang theory

    Directory of Open Access Journals (Sweden)

    Sarah Aretz

    2016-12-01

    However, it is not yet clear in science education if students’ conceptions about the Big Bang vary by nationality, and therefore, if it is possible to apply the same teaching modules to students from different countries, who may have diverse social and cultural backgrounds and different curricula. These conceptions with which students enter the classroom were investigated in our study. We implemented an open-ended questionnaire survey in Germany, with questions based on recent U.S. studies. The results clearly showed, with high interrater reliabilities, widespread misconceptions like the Big Bang being an explosion of preexisting matter into empty space or the universe having a centre. Furthermore, a comparison of results from researchers in the USA, Sweden and Germany allowed us to identify differences in students’ conceptions between the countries. Our findings appear to indicate that German students have slightly better pre-instructional conceptions about the Big Bang theory.

  10. The big bang of genome editing technology: development and application of the CRISPR/Cas9 system in disease animal models.

    Science.gov (United States)

    Shao, Ming; Xu, Tian-Rui; Chen, Ce-Shi

    2016-07-18

    Targeted genome editing technology has been widely used in biomedical studies. The CRISPR-associated RNA-guided endonuclease Cas9 has become a versatile genome editing tool. The CRISPR/Cas9 system is useful for studying gene function through efficient knock-out, knock-in or chromatin modification of the targeted gene loci in various cell types and organisms. It can be applied in a number of fields, such as genetic breeding, disease treatment and gene functional investigation. In this review, we introduce the most recent developments and applications, the challenges, and future directions of Cas9 in generating disease animal model. Derived from the CRISPR adaptive immune system of bacteria, the development trend of Cas9 will inevitably fuel the vital applications from basic research to biotechnology and bio-medicine.

  11. Big Bang Day: 5 Particles - 1. The Electron

    CERN Multimedia

    Simon Singh

    2008-01-01

    Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 1. The Electron Just over a century ago, British physicist J.J. Thompson experimenting with electric currents and charged particles inside empty glass tubes, showed that atoms are divisible into indivisible elementary particles. But how could atoms be built up of these so called "corpuscles"? An exciting 30 year race ensued, to grasp the planetary model of the atom with its orbiting electrons, and the view inside the atom was born. Whilst the number of electrons around the nucleus of an atom determines their the chemistry of all elements, the power of electrons themselves have been harnessed for everyday use: electron beams for welding,cathode ray tubes and radiation therapy.

  12. Big-bang nucleosynthesis with high-energy photon injection

    Energy Technology Data Exchange (ETDEWEB)

    Holtmann, Erich N. [Univ. of California, Berkeley, CA (United States)

    1999-05-01

    The author discusses the photodissociation of light elements due to the radiative decay of a massive particle, and he has shown how to constrain the model parameters from the observed light-element abundances. He adopted two quasar absorption system (QAS) D/H values, as well as solar system data for D/H and 3He/H. For each of these, he used two 4He values. He presents his results in terms of the confidence level at which each theoretical parameter set (i.e., the set of properties of a radiatively decaying particle) is excluded by the observed abundances. His algorithm for computing the confidence level is consistent and general enough to apply not only to the scenarios investigated in this work, but also to many other non-standard theories of BBN.

  13. On initial conditions for the Hot Big Bang

    CERN Document Server

    Bezrukov, F; Shaposhnikov, M

    2008-01-01

    We analyse the process of reheating the Universe in the electroweak theory where the Higgs field plays a role of the inflaton. We estimate the maximal temperature of the Universe and fix the initial conditions for radiation-dominated phase of the Universe expansion in the framework of the nuMSM--the minimal extension of the Standard Model (SM) by three right-handed singlet fermions. We show that the inflationary epoch is followed by a matter dominated stage related to the Higgs field oscillations. We investigate the energy transfer from higgs-inflaton to the SM particles and show that the radiation dominated phase of the Universe expansion starts at temperature T_r ~ (3-8)*10^{13} GeV. We estimate the production rate of singlet fermions at preheating and find that their concentrations at T_r are negligibly small. This suggests that the sterile neutrino Dark Matter (DM) production and baryogenesis in the nuMSM with higgs driven inflation are low energy phenomena, having nothing to do with inflation. We study t...

  14. Classical and quantum Big Brake cosmology for scalar field and tachyonic models

    Energy Technology Data Exchange (ETDEWEB)

    Kamenshchik, A. Yu. [Dipartimento di Fisica e Astronomia and INFN, Via Irnerio 46, 40126 Bologna (Italy) and L.D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences, Kosygin str. 2, 119334 Moscow (Russian Federation); Manti, S. [Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy)

    2013-02-21

    We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models based on a tachyon-pseudo-tachyon field . It is shown that the effect of quantum avoidance is absent for the soft singularities of the Big Brake type while it is present for the Big Bang and Big Crunch singularities. Thus, there is some kind of a classical - quantum correspondence, because soft singularities are traversable in classical cosmology, while the strong Big Bang and Big Crunch singularities are not traversable.

  15. Classical and quantum Big Brake cosmology for scalar field and tachyonic models

    CERN Document Server

    Kamenshchik, A

    2013-01-01

    We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models based on a tachyon-pseudo-tachyon field . It is shown that the effect of quantum avoidance is absent for the soft singularities of the Big Brake type while it is present for the Big Bang and Big Crunch singularities. Thus, there is some kind of a classical - quantum correspondence, because soft singularities are traversable in classical cosmology, while the strong Big Bang and Big Crunch singularities are not traversable.

  16. Classical and Quantum Big Brake Cosmology for Scalar Field and Tachyonic Models

    Science.gov (United States)

    Kamenshchik, Alexander; Manti, Serena

    2015-01-01

    We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models based on a tachyon-pseudo-tachyon field. It is shown that the effect of quantum avoidance is absent for the soft singularities of the Big Brake type while it is present for the Big Bang and Big Crunch singularities. Thus, there is some kind of a classical - quantum correspondence, because soft singularities are traversable in classical cosmology, while the strong Big Bang and Big Crunch singularities are not traversable.

  17. Don’t miss the Passport to the Big Bang event this Sunday!

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    Word has been going around for weeks now about the inauguration of the Passport to the Big Bang on Sunday 2 June. Ideal for a family day out or a day with friends, this is a CERN event not to be missed!   The Passport to the Big Bang is a 54-km scientific tourist trail comprising ten exhibition platforms in front of ten CERN sites in the Pays de Gex and the Canton of Geneva. Linked by cycle routes, these ten platforms will mark the same number of stages in the rally for competitive cyclists and the bicycle tour for families taking place this Sunday from 9 a.m. to 12 p.m. But that’s not all: from 2 p.m., you will also have the chance to take part in a huge range of activities provided by clubs and associations from CERN and the local region. Watch an oriental dance show, have a go at building detectors out of Kapla blocks and Lego, meet different reptile species, learn about wind instruments, try your hand at Nordic walking or Zumba fitness, get a better understanding of road safety...

  18. Pre-big bang bubbles from the gravitational instability of generic string vacua

    CERN Document Server

    Buonanno, A; Veneziano, Gabriele

    1999-01-01

    We formulate the basic postulate of pre-big bang cosmology as one of ``asymptotic past triviality'', by which we mean that the initial state is a generic perturbative solution of the tree-level low-energy effective action. Such a past-trivial ``string vacuum'' is made of an arbitrary ensemble of incoming gravitational and dilatonic waves, and is generically prone to gravitational instability, leading to the possible formation of many black holes hiding singular space-like hypersurfaces. Each such singular space-like hypersurface of gravitational collapse becomes, in the string-frame metric, the usual big-bang t=0 hypersurface, i.e. the place of birth of a baby Friedmann universe after a period of dilaton-driven inflation. Specializing to the spherically-symmetric case, we review and reinterpret previous work on the subject, and propose a simple, scale-invariant criterion for collapse/inflation in terms of asymptotic data at past null infinity. Those data should determine whether, when, and where collapse/infl...

  19. The amazing unity of the Universe and its origin in the Big Bang

    CERN Document Server

    van den Heuvel, Edward

    2016-01-01

    In the first chapters the author describes how our knowledge of the position of Earth in space and time has developed, thanks to the work of many generations of astronomers and physicists. He discusses how our position in the Galaxy was discovered, and how in 1929, Hubble uncovered the fact that the Universe is expanding, leading to the picture of the Big Bang. He then explains how astronomers have found that the laws of physics that were discovered here on Earth and in the Solar System (the laws of mechanics, gravity, atomic physics, electromagnetism, etc.) are valid throughout the Universe. This is illustrated by the fact that all matter in the Universe consists of atoms of the same chemical elements that we know on Earth. This unity is all the more surprising when one realizes that in the original Big Bang theory, different parts of the Universe could never have communicated with each other. It then is a mystery how they could have shared the same physical laws. This problem was solved by the introduction ...

  20. A big bang in a little room the quest to create new universes

    CERN Document Server

    Merali, Zeeya

    2017-01-01

    What if you could become God, with the ability to build a whole new universe? As startling as it sounds, modern physics suggests that within the next two decades, scientists may be able to perform this seemingly divine feat-to concoct an entirely new baby universe, complete with its own physical laws, star systems, galaxies, and even intelligent life. A Big Bang in a Little Room takes the reader on a journey through the history of cosmology and unravels-particle by particle, theory by theory, and experiment by experiment-the ideas behind this provocative claim made by some of the most respected physicists alive today. Beyond simply explaining the science, A Big Bang in a Little Room also tells the story of the people who have been laboring for more than thirty years to make this seemingly impossible dream a reality. What has driven them to continue on what would seem, at first glance, to be a quixotic quest? This mind-boggling book reveals that we can nurse other worlds in the tiny confines of a lab, raising...

  1. A large neutral fraction of cosmic hydrogen a billion years after the Big Bang.

    Science.gov (United States)

    Wyithe, J Stuart B; Loeb, Abraham

    2004-02-26

    The fraction of ionized hydrogen left over from the Big Bang provides evidence for the time of formation of the first stars and quasar black holes in the early Universe; such objects provide the high-energy photons necessary to ionize hydrogen. Spectra of the two most distant known quasars show nearly complete absorption of photons with wavelengths shorter than the Lyman alpha transition of neutral hydrogen, indicating that hydrogen in the intergalactic medium (IGM) had not been completely ionized at a redshift of z approximately 6.3, about one billion years after the Big Bang. Here we show that the IGM surrounding these quasars had a neutral hydrogen fraction of tens of per cent before the quasar activity started, much higher than the previous lower limits of approximately 0.1 per cent. Our results, when combined with the recent inference of a large cumulative optical depth to electron scattering after cosmological recombination therefore suggest the presence of a second peak in the mean ionization history of the Universe.

  2. Implication of the Proton-Deuteron Radiative Capture for Big Bang Nucleosynthesis.

    Science.gov (United States)

    Marcucci, L E; Mangano, G; Kievsky, A; Viviani, M

    2016-03-11

    The astrophysical S factor for the radiative capture d(p,γ)^{3}He in the energy range of interest for big bang nucleosynthesis (BBN) is calculated using an ab initio approach. The nuclear Hamiltonian retains both two- and three-nucleon interactions-the Argonne v_{18} and the Urbana IX, respectively. Both one- and many-body contributions to the nuclear current operator are included. The former retain for the first time, besides the 1/m leading order contribution (m is the nucleon mass), also the next-to-leading order term, proportional to 1/m^{3}. The many-body currents are constructed in order to satisfy the current conservation relation with the adopted Hamiltonian model. The hyperspherical harmonics technique is applied to solve the A=3 bound and scattering states. Particular attention is paid in this second case in order to obtain, in the energy range of BBN, an uncertainty on the astrophysical S factor of the order or below ∼1%. Then, in this energy range, the S factor is found to be ∼10% larger than the currently adopted values. Part of this increase (1%-3%) is due to the 1/m^{3} one-body operator, while the remaining is due to the new more accurate scattering wave functions. We have studied the implication of this new determination for the d(p,γ)^{3}He S factor on the deuterium primordial abundance. We find that the predicted theoretical value for ^{2}H/H is in excellent agreement with its experimental determination, using the most recent determination of the baryon density of the Planck experiment, and with a standard number of relativistic degrees of freedom N_{eff}=3.046 during primordial nucleosynthesis. This calls for a more accurate measurement of the astrophysical S factor in order to confirm the present predictions.

  3. Geneva Festival, 2004: Opened with the Big Bang, closed with Creation

    CERN Multimedia

    2004-01-01

    In its 50th Anniversary year, CERN had the honour of opening and closing this year's Geneva Festival. The Geneva Festival traditionally opens with a bang, but this year's was the biggest yet. On 30 July, on a warm summer's evening by Lake Geneva, several tons of fireworks replayed the early history of the Universe. Starting with the Big Bang, the display had acts representing inflation, the breaking of symmetries, the clash of antimatter and matter, hadrons and nucleosynthesis, the first atoms and the Universe becoming transparent, and the formation of stars and planets. It was a challenge to translate these very abstract ideas into more than a thousand kilograms of TNT of different colour. But, set to the music of The Matrix, Alan Parsons, and Jurassic Park, one of the most spectacular physics presentations ever staged dazzled the audience of two hundred thousand spectators. CERN physicist Rolf Landua, who scripted the narrative and worked with the pyrotechnicians on the realization, said: "From the many e...

  4. Relic High Frequency Gravitational waves from the Big Bang, and How to Detect Them

    CERN Document Server

    Beckwith, A W

    2008-01-01

    We show generic conditions for HFGW detection, employing a novel entropy concept written up by Jack Ng, and Steinhard's proceedure for reconstructing tensorial representations for relic HFGW from the onset of the big bang. The issue of the reality of gravitons as a measurable physical object so eloquently raised by Rothman in 2006 is indirectly answered via a proceedure obtained from Weinberg's 1972 book on gravitation, and all the methodologies so obtained are referenced with respect to the engineering specifications of the Li-Baker HFGW detector. In addition, the document also refers to entanglement entropy, and its possible aid in refining measurement predictions by the Li-Baker HFGW detector, using Dr. Yeo's 2006 EPL paper

  5. “I am a rogue night elf”: Avatars, gaming and The Big Bang Theory

    Directory of Open Access Journals (Sweden)

    Theo Plothe

    2014-03-01

    Full Text Available CBS’s The Big Bang Theory (TBBT frequently exhibits elements of video games and gaming culture. The author uses subculture theory to consider the representation of video games, gamers, and their avatars within popular culture. This paper investigates the representation of avatars within the characterization of gaming subculture on the TBBT. The author performed a content analysis of the program’s six seasons, examining the relationship between the show’s video game playing characters and their avatars. This investigation found that almost half of the scenes that contained video gaming activities contained some aspect of avatars. TBBT reifies gaming as a subculture through the relationship between the characters and their avatars. Examining the representation of these relationships is essential to understanding the representation of the gaming subculture in the mass media and within culture at large.

  6. Revisiting constraints on small scale perturbations from big-bang nucleosynthesis

    Science.gov (United States)

    Inomata, Keisuke; Kawasaki, Masahiro; Tada, Yuichiro

    2016-08-01

    We revisit the constraints on the small scale density perturbations (1 04 Mpc-1≲k ≲1 05 Mpc-1 ) from the modification of the freeze-out value of the neutron-proton ratio at the big-bang nucleosynthesis era. Around the freeze-out temperature T ˜0.5 MeV , the universe can be divided into several local patches that have different temperatures since any perturbation that enters the horizon after the neutrino decoupling has not diffused yet. Taking account of this situation, we calculate the freeze-out value in detail. We find that the small scale perturbations decrease the n -p ratio in contrast to previous works. With the use of the latest observed 4He abundance, we obtain the constraint on the power spectrum of the curvature perturbations as ΔR2≲0.018 on 1 04 Mpc-1≲k ≲1 05 Mpc-1 .

  7. 178th International School of Physics "Enrico Fermi" : From the Big Bang to the Nucleosynthesis

    CERN Document Server

    Nappi, E

    2011-01-01

    Physicists have devoted much effort to reproducing the conditions of the primordial universe in laboratory conditions in their quest to work out a comprehensive theory of the appearance and evolution of nuclear matter. Whether it be trying to recreate the predicted primordial state of high-energy density matter in which quarks and gluons are effectively deconfined - the so-called Quark Gluon Plasma (QGP) - or exploring the structure and reaction properties of very unstable nuclei in experiments using radioactive beams, they have striven to understand the events which characterized the Big Bang and the various nucleosynthesis mechanisms which occur in the stars. This book contains the proceedings of the 2010 Enrico Fermi summer school held in Varenna, Italy, in July 2010, and devoted to the present understanding of the primordial universe and the origin of the elements, as achieved by studying nuclei and their constituents in extreme regimes of energy and composition. Subjects covered include: QGP formation; e...

  8. Dust production 0.7-1.5 billion years after the Big Bang

    CERN Document Server

    Michałowski, Michał J

    2015-01-01

    Cosmic dust is an important component of the Universe, and its origin, especially at high redshifts, is still unknown. I present a simple but powerful method of assessing whether dust observed in a given galaxy could in principle have been formed by asymptotic giant branch (AGB) stars or supernovae (SNe). Using this method I show that for most of the galaxies with detected dust emission between z=4 and z=7.5 (1.5-0.7 billion years after the Big Bang) AGB stars are not numerous and efficient enough to be responsible for the measured dust masses. Supernovae could account for most of the dust, but only if all of them had efficiencies close to the maximal theoretically allowed value. This suggests that a different mechanism is responsible for dust production at high redshifts, and the most likely possibility is the grain growth in the interstellar medium.

  9. On Big Bang Relics, the Neutrino Mass and the Spectrum of Cosmic Rays

    CERN Document Server

    Wigmans, R

    2000-01-01

    It is shown that high-energy features of the cosmic ray spectrum, in particular the kink around 4 PeV and the corresponding change in spectral index, may be explained from interactions between highly energetic cosmic protons and relic Big Bang antineutrinos, if the latter have a rest mass of about 0.4 eV/$c^2$. This explanation is supported by experimental data from extensive air-shower experiments, and in particular by the observation (Fly's Eye) of a second kink around 300 PeV, and by the abrupt change in the chemical composition of the cosmic ray spectrum that occurs at that energy. Both facts follow naturally from our theory, which predicts additional verifiable features of the cosmic ray spectrum in the few-PeV region, e.g. an abrupt decrease in the $p/\\alpha$ ratio.

  10. From the Big Bang to the Nobel Prize and the JWST

    Science.gov (United States)

    Mather, John C.

    2007-01-01

    I will describe the history of the universe, from the Big Bang to 2013, when the JWST is to be launched to look back towards our beginnings. I will discuss how the COBE results led to the Nobel Prize, how the COBE results have been confirmed and extended, and their implications for future observations. The James Webb Space Telescope will be used to examine every part of our history from the first stars and galaxies to the formation of individual stars and planets and the delivery of life-supporting materials to the Earth. I will describe the plans for the JWST and how observers may use it. With luck, the JWST may produce a Nobel Prize for some discovery we can only guess today.

  11. 宇舶表 Big Bang In Red-2010年绚丽登场

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    2010年情人节来临之际,瑞士著名手表品牌Hublot宇舶表特别推出Big Bang In Red腕表。表款整体选用红色这一诠释浪漫经典爱情的永厘颜色,尽在绚丽、妩媚优雅。镶钻深红色表盘、白色陶瓷表壳与天然橡胶内衬的鳄鱼真皮腕带完美结合,尽显宇舶表“融合之艺术”的设计理念。

  12. Quantum mechanics before the big bang in heterotic-M-theory

    CERN Document Server

    Zanzi, Andrea

    2016-01-01

    In this letter we investigate the role played by quantum mechanics before the big-bang in heterotic-M-theory assuming an orbifold compactification of time. As we will see particles are localized around a black hole but only in regions where a constructive quantum interference takes place. We infer that the creation of this interference pattern is interesting for many reasons: (A) it is a mechanism to localize particles on $S^4$ branes; (B) the Casimir potential for the dilaton can be interpreted as a gravitational effective potential for a two-body problem; (C) the quantum interference is a new way to define the branes in heterotic-M-theory. Remarkably, a modified Schroedinger equation is obtained. The stabilization of the branes' position is related to the absence of a cosmological singularity.

  13. The Big Bang of picorna-like virus evolution antedates the radiation of eukaryotic supergroups.

    Science.gov (United States)

    Koonin, Eugene V; Wolf, Yuri I; Nagasaki, Keizo; Dolja, Valerian V

    2008-12-01

    The recent discovery of RNA viruses in diverse unicellular eukaryotes and developments in evolutionary genomics have provided the means for addressing the origin of eukaryotic RNA viruses. The phylogenetic analyses of RNA polymerases and helicases presented in this Analysis article reveal close evolutionary relationships between RNA viruses infecting hosts from the Chromalveolate and Excavate supergroups and distinct families of picorna-like viruses of plants and animals. Thus, diversification of picorna-like viruses probably occurred in a 'Big Bang' concomitant with key events of eukaryogenesis. The origins of the conserved genes of picorna-like viruses are traced to likely ancestors including bacterial group II retroelements, the family of HtrA proteases and DNA bacteriophages.

  14. Observational Constraint on Heavy Element Production in Inhomogeneous Big Bang Nucleosynthesis

    CERN Document Server

    Nakamura, Riou; Fujimoto, Shin-ichiro; Nishimura, Nobuya; Sato, Katsuhiko

    2010-01-01

    Based on a scenario of the inhomogeneous big-bang nucleosynthesis (IBBN), we investigate the detailed nucleosynthesis that includes the production of heavy elements beyond Li-7. From the observational constraints on light elements of He4 and D for the baryon-to-photon ratio given by WMAP, possible regions found on the plane of the volume fraction of the high density region against the ratio between high- and low-density regions. In these allowed regions, we have confirmed that the heavy elements beyond Fe can be produced appreciably, where p- and/or r-process elements are produced well simultaneously compared to the solar system abundances. We suggest that recent observational signals such as He4 overabundance in globular clusters and high metallicity abundances in quasars could be partly due to the results of IBBN. Possible implications are given for the formation of the first generation stars

  15. From Big Crunch to Big Bang A Quantum String Cosmology Perspective

    CERN Document Server

    Maharana, J

    2002-01-01

    The scenario that the Universe contracts towards a big crunch and then undergoes a transition to expanding Universe in envisaged in the quantum string cosmology approach. The Wheeler-De Witt equation is solved exactly for an exponential dilaton potential. S-duality invariant cosmological effective action, for type IIB theory, is considered to derive classical solutions and solve WDW equations.

  16. Nobel Lecture: From the Big Bang to the Nobel Prize and beyond

    Science.gov (United States)

    Mather, John C.

    NASA’s Cosmic Background Explorer satellite mission, the COBE, laid the foundations for modern cosmology by measuring the spectrum and anisotropy of the cosmic microwave background radiation and discovering the cosmic infrared background radiation. I describe the history of the COBE project, its scientific context, the people who built it, and the scientific results. The COBE observed the universe on the largest scales possible by mapping the cosmic microwave and infrared background radiation fields and determining their spectra. It produced conclusive evidence that the hot Big Bang theory of the early universe is correct, showed that the early universe was very uniform but not perfectly so, and that the total luminosity of post Big Bang objects is twice as great as previously believed. The COBE concept was developed by a Mission Definition Study Team appointed by NASA in 1976, based on three competing proposals submitted in 1974. The COBE was built in-house by Goddard Space Flight Center, with a helium cryostat provided by Ball Aerospace, and was launched on a Delta rocket built by McDonnell Douglas. It is in a circular orbit 900km above the Earth, in a plane inclined 99° to the equator and roughly perpendicular to the line to the Sun. It carried three instruments, a far infrared absolute spectrophotometer (FIRAS), a differential microwave radiometer with three channels (DMR), and a diffuse infrared background experiment (DIRBE). The helium cryostat cooled the FIRAS and DIRBE for 10months until the helium was exhausted, but operations continued for a total of 4years . Subsequent observations have confirmed the COBE results and led to measurements of the main cosmological parameters with a precision of a few percent.

  17. Indeterministic Quantum Gravity and Cosmology; 7, Dynamical Passage through Singularities Black Hole and Naked Singularity, Big Crunch and Big Bang

    CERN Document Server

    Mashkevich, V S

    1997-01-01

    This paper is a continuation of the papers [gr-qc/9409010, gr-qc/9505034, gr-qc/9603022, gr-qc/9609035, gr-qc/9609046, gr-qc/9704033]. The aim of the paper is to incorporate singularities---both local (black hole and naked singularity) and global (big bang and big crunch)---into the dynamics of indeterministic quantum gravity and cosmology. The question is whether a singularity is dynamically passable, i.e., whether a dynamical process which ends with a singularity may be extended beyond the latter. The answer is yes. A local singularity is trivially passable, while the passableness for a global singularity may invoke CPT transformation. The passableness of the singularities implies pulsating black holes and the oscillating universe. For the local singularity, the escape effect takes place: In a vicinity of the singularity, quantum matter leaves the gravitational potential well. Keywords: tempered singularity, strong singularity, trivial passage, CPT passage, pulsating black hole, escape effect, oscillating u...

  18. Big Bang-Big Crunch Algorithm for Voltage Stability Limit Improvement by Coordinated Control of SVC Settings

    Directory of Open Access Journals (Sweden)

    S. Sakthivel

    2013-07-01

    Full Text Available Modern power system networks are operated under highly stressed conditions and there is a risk of voltage instability problems owing to increased load demand. A power system needs to be with sufficient voltage stability margin for secured operation. In this study, SVC parameters of location and size along with generator bus voltages, transformer tap settings are considered as control parameters for voltage stability limit improvement by minimizing loss and voltage deviation. The control parameters are varied in a coordinated manner for better results. The line based LQP voltage stability indicator is used for voltage stability assessment. The nature inspired meta heuristic Big Bang-Big Crunch (BB-BC algorithm is exploited for optimization of the control variables and the performance is compared with that of PSO algorithm. The effectiveness of the proposed algorithm is tested on the standard IEEE 30 bus system under normal and N-1 line outage contingency conditions. The results obtained from the simulation encourage the performances of the new algorithm.

  19. Change of government: one more big bang health care reform in England's National Health Service.

    Science.gov (United States)

    Hunter, David J

    2011-01-01

    Once again the National Health Service (NHS) in England is undergoing major reform, following the election of a new coalition government keen to reduce the role of the state and cut back on big government. The NHS has been undergoing continuous reform since the 1980s. Yet, despite the significant transaction costs incurred, there is no evidence that the claimed benefits have been achieved. Many of the same problems endure. The reforms follow the direction of change laid down by the last Conservative government in the early 1990s, which the recent Labour government did not overturn despite a commitment to do so. Indeed, under Labour, the NHS was subjected to further market-style changes that have paved the way for the latest round of reform. The article considers the appeal of big bang reform, questions its purpose and value, and critically appraises the nature and extent of the proposed changes in this latest round of reform. It warns that the NHS in its current form may not survive the changes, as they open the way to privatization and a weakening of its public service ethos.

  20. BICEP2, Planck, spinorial space-time, pre-Big Bang.

    Directory of Open Access Journals (Sweden)

    Gonzalez-Mestres Luis

    2015-01-01

    Full Text Available The field of Cosmology is currently undergoing a positive and constructive crisis. Controversies concerning inflation are not really new. But after the 2013-2014 Planck and BICEP2 announcements, and the more recent joint analysis by Planck, BICEP2 and the Keck Array (PBKA, the basic issues can involve more direct links between the Mathematical Physics aspects of cosmological patterns and the interpretation of experimental results. Open questions and new ideas on the foundations of Cosmology can emerge, while future experimental and observational programs look very promising. The BICEP2 result reporting an excess of B-mode polarization signal of the cosmic microwave background (CMB radiation was initially presented as a signature of primordial gravitational waves from cosmic inflation. But polarized dust emission can be at the origin of such a signal, and the evidence claimed by BICEP2 is no longer secure after the PBKA analysis. Furthermore, even assuming that significant CMB B-mode polarization has indeed been generated by the early Universe, its theoretical and cosmological interpretation would be far from obvious. Inflationary gravitational waves are not the only possible source of primordial CMB B-modes. Alternative cosmologies such as pre-Big Bang patterns and the spinorial space-time (SST we introduced in 1996-97 can naturally produce this polarization. Furthermore, the SST automatically generates for each comoving observer a local privileged space direction (PSD whose existence may have been confirmed by Planck data. If such a PSD exists, vector perturbations have most likely been strong in the early Universe and may have produced CMB B-modes. Pre-Big Bang cosmologies can also generate gravitational waves in the early Universe without inflation. After briefly describing detectors devoted to the study of the CMB polarization, we discuss the situation emerging from BICEP2 results, Planck results and the PBKA analysis. In particular, we

  1. 字幕翻译中幽默元素的翻译--以The Big Bang Theory为例

    Institute of Scientific and Technical Information of China (English)

    乐迁

    2016-01-01

    幽默可分为三类:语言幽默、文化幽默和普义幽默。每类幽默的特点决定了翻译时译员要采取不同的策略。本文通过对翻译The Big Bang Theory中幽默的讨论,探索各类幽默可行的翻译方法。

  2. Limits on Cosmological Variation of Strong Interaction and Quark Masses from Big Bang Nucleosynthesis, Cosmic, Laboratory and Oklo Data

    CERN Document Server

    Flambaum, V V

    2002-01-01

    Recent data on cosmological variation of the electromagnetic fine structure constant from distant quasar (QSO) absorption spectra have inspired a more general discussion of possible variation of other constants. We discuss variation of strong scale and quark masses. We derive the limits on their relative change from (i) primordial Big-Bang Nucleosynthesis (BBN); (ii) Oklo natural nuclear reactor, (iii) quasar absorption spectra, and (iv) laboratory measurements of hyperfine intervals.

  3. A study on the Translation of Cultural Elements in TV Subtitles-A Case Study of The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    胡亚庆

    2014-01-01

    With the growing popularity of one country’s TV series in foreign countries, subtitle translation has attracted consider-able attention in recent years. The Big Bang Theory (TBBT) is a widespread American TV series whose subtitles have been trans-lated into many foreign languages, and it also boasts its richness in cultural elements, the most typical ones including science ele-ments and religious cultural elements.

  4. Conference | The Big Bang and the interfaces of knowledge: towards a common understanding? | 11 November

    CERN Multimedia

    2015-01-01

    The third in a series of conferences organised by CERN and Wilton Park, this event will once again bring together scientists, theologians and philosophers to discuss the themes of the nature and understanding of a common language, truth and logic.   Wednesday, 11 November at 4 p.m. in the Main Auditorium For more information and to register, click here. In 2012, CERN and Wilton Park hosted the pioneering international conference “The Big Bang and the interfaces of knowledge: towards a common language?”. The event was very successful and a follow-up conference was organised in June 2014 with the purpose of widening the spectrum of scientists, theologians and philosophers involved, continuing the dialogue on one of the key themes that emerged during the first meeting: the nature and the understanding of “truth”. A key theme emerging from the 2014 event was the nature and understanding of logic, and this third meeting will focu...

  5. Comparison of Plasma-Redshift Cosmology and Big-Bang Cosmology

    Science.gov (United States)

    Brynjolfsson, Ari

    2009-05-01

    Plasma redshift is derived theoretically from conventional axioms of physics by using more accurate methods than those conventionally used. The main difference is the proper inclusion of the dielectric constant. The force acting on the electron is proportional to E=D/ɛ and not D as is conventionally surmised. This correction is not important in ordinary laboratory plasmas; but in the hot sparse plasmas of the intergalactic space, it explains the gradual energy loss (the cosmological redshift) of photons. This energy loss of photons is transferred to the plasma and makes it very hot. The plasma redshift explains long range of phenomena, including the intrinsic redshift of Sun, stars, galaxies and quasars, and the cosmological redshift. It explains also the beautiful black body spectrum of the CMB, and it predicts the observed XRB, and much more. There is no need for Big Bang, Inflation, Dark Energy, Dark Matter, Black Holes and much more. The universe is quasi-static and can renew itself forever. There is no cosmic time dilation. In intergalactic space the average temperature is 2.7.10^6 K, and the average electron density (Ne)avg= 2 .10-4 cm-3.

  6. HD 140283: A STAR IN THE SOLAR NEIGHBORHOOD THAT FORMED SHORTLY AFTER THE BIG BANG

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Howard E.; Nelan, Edmund P. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States); VandenBerg, Don A. [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, BC V8W 3P6 (Canada); Schaefer, Gail H. [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Harmer, Dianne, E-mail: bond@stsci.edu, E-mail: nelan@stsci.edu, E-mail: vandenbe@uvic.ca, E-mail: schaefer@chara-array.org, E-mail: diharmer@noao.edu [National Optical Astronomy Observatories, 950 North Cherry Avenue, Tucson, AZ 85726 (United States)

    2013-03-01

    HD 140283 is an extremely metal-deficient and high-velocity subgiant in the solar neighborhood, having a location in the Hertzsprung-Russell diagram where absolute magnitude is most sensitive to stellar age. Because it is bright, nearby, unreddened, and has a well-determined chemical composition, this star avoids most of the issues involved in age determinations for globular clusters. Using the Fine Guidance Sensors on the Hubble Space Telescope, we have measured a trigonometric parallax of 17.15 {+-} 0.14 mas for HD 140283, with an error one-fifth of that determined by the Hipparcos mission. Employing modern theoretical isochrones, which include effects of helium diffusion, revised nuclear reaction rates, and enhanced oxygen abundance, we use the precise distance to infer an age of 14.46 {+-} 0.31 Gyr. The quoted error includes only the uncertainty in the parallax, and is for adopted surface oxygen and iron abundances of [O/H] = -1.67 and [Fe/H] = -2.40. Uncertainties in the stellar parameters and chemical composition, especially the oxygen content, now contribute more to the error budget for the age of HD 140283 than does its distance, increasing the total uncertainty to about {+-}0.8 Gyr. Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 {+-} 0.06 Gyr, based on the microwave background and Hubble constant, but it must have formed soon after the big bang.

  7. From the big bang to cleaner teeth - doppler shift - a practical engineering tool

    Energy Technology Data Exchange (ETDEWEB)

    Traynor, R [Vibrometry and Velocimetry Product Specialist, Lambda Photometrics Ltd, UK Division of Polytec GmbH, Lambda House, Batford Mill, Harpenden, Hertfordshire, AL5 5BZ (United Kingdom)], E-mail: roger@lambdaphoto.co.uk

    2008-03-01

    Many basic engineering techniques rely on fundamental science that is so well embedded and accepted, that it becomes effectively 'invisible' to the average user. Doppler Shift is one such physical phenomenon that is widely used throughout science and engineering, but often without being noticed. Probably the most familiar scientific application of Doppler is the measurement of the speed of stars, to identify the expansion of the Universe since the 'Big Bang'. But in engineering and R and D, it can and is being used as a powerful vibration measurement tool. Using laser-based interferometric techniques, with Doppler Frequency Shifting in one path of the interferometer, velocities and displacements as subtle as those of the hearing mechanisms of flies and as fierce as the motion of Formula 1 engines valves can be measured This paper describes the basics of Doppler Shift and its use within Laser Doppler Vibration and Velocity measurement instruments. It will cover the extremely wide performance capabilities of the technique and the practical advantages of such instruments, with some practical examples of how and where they are currently being used. Of these examples, many are unique and would not be practical or even feasible without the availability of such tools.

  8. A Note on the Quantization Mechanism within the Cold Big Bang Cosmology

    Directory of Open Access Journals (Sweden)

    Assis A. V. D. B.

    2011-10-01

    Full Text Available In my paper [3], I obtain a Cold Big Bang Cosmology, fitting the cosmological data, with an absolute zero primordial temperature, a natural cutoff for the cosmological data to a vanishingly small entropy at a singular microstate of a comoving domain of the cos- mological fluid. This solution resides on a negative pressure solution from the general relativity field equation and on a postulate regarding a Heisenberg indeterminacy mech- anism related to the energy fluctuation obtained from the solution of the field equations under the Robertson-Walker comoving elementar line element context in virtue of the adoption of the Cosmological Principle. In this paper, we see the, positive, differential energy fluctuation, purely obtained from the general relativity cosmological solution in [3], leads to the quantum mechanical argument of the postulate in [3], provided this energy fluctuation is quantized, strongly supporting the postulate in [3]. I discuss the postulate in [3], showing the result for the energy fluctuation follows from a discreteness hypothesis.

  9. The Interstellar Medium In Galaxies Seen A Billion Years After The Big Bang

    CERN Document Server

    Capak, P L; Jones, G; Casey, C M; Riechers, D; Sheth, K; Carollo, C M; Ilbert, O; Karim, A; LeFevre, O; Lilly, S; Scoville, N; Smolcic, V; Yan, L

    2015-01-01

    Evolution in the measured rest frame ultraviolet spectral slope and ultraviolet to optical flux ratios indicate a rapid evolution in the dust obscuration of galaxies during the first 3 billion years of cosmic time (z>4). This evolution implies a change in the average interstellar medium properties, but the measurements are systematically uncertain due to untested assumptions, and the inability to measure heavily obscured regions of the galaxies. Previous attempts to directly measure the interstellar medium in normal galaxies at these redshifts have failed for a number of reasons with one notable exception. Here we report measurements of the [CII] gas and dust emission in 9 typical (~1-4L*) star-forming galaxies ~1 billon years after the big bang (z~5-6). We find these galaxies have >12x less thermal emission compared with similar systems ~2 billion years later, and enhanced [CII] emission relative to the far-infrared continuum, confirming a strong evolution in the interstellar medium properties in the early u...

  10. First life in primordial-planet oceans: the biological big bang

    CERN Document Server

    Gibson, Carl H; Schild, Rudolph E

    2010-01-01

    A scenario is presented for the formation of first life in the universe based on hydro-gravitational-dynamics (HGD) cosmology. From HGD, the dark matter of galaxies is H-He gas dominated planets (primordial-fog-particle PFPs) in million solar mass clumps (protoglobularstarcluster PGCs), which formed at the plasma to gas transition temperature 3000 K. Stars result from mergers of the hot-gas-planets. Over-accretion causes stars to explode as supernovae that scatter life-chemicals (C, N, O, P, S, Ca, Fe etc.) to other planets in PGC clumps and beyond. These chemicals were first collected gravitationally by merging PFPs to form H-saturated, high-pressure, dense oceans of critical-temperature 647 K water over iron-nickel cores at ~ 2 Myr. Stardust fertilizes the formation of first life in a cosmic hot-ocean soup kitchen comprised of all planets and their moons in meteoric communication, > 10^100 kg in total. Ocean freezing slows this biological big bang at ~ 8 Myr. HGD cosmology confirms that the evolving seeds o...

  11. Georges Lemaître: The Priest Who Invented the Big Bang

    Science.gov (United States)

    Lambert, Dominique

    This contribution gives a concise survey of Georges Lemaître works and life, shedding some light on less-known aspects. Lemaître is a Belgian catholic priest who gave for the first time in 1927 the explanation of the Hubble law and who proposed in 1931 the "Primeval Atom Hypothesis", considered as the first step towards the Big Bang cosmology. But the scientific work of Lemaître goes far beyond Physical Cosmology. Indeed, he contributed also to the theory of Cosmis Rays, to the Spinor theory, to Analytical mechanics (regularization of 3- Bodies problem), to Numerical Analysis (Fast Fourier Transform), to Computer Science (he introduced and programmed the first computer of Louvain),… Lemaître took part to the "Science and Faith" debate. He defended a position that has some analogy with the NOMA principle, making a sharp distinction between what he called the "two paths to Truth" (a scientific one and a theological one). In particular, he never made a confusion between the theological concept of "creation" and the scientific notion of "natural beginning" (initial singularity). Lemaître was deeply rooted in his faith and sacerdotal vocation. Remaining a secular priest, he belonged to a community of priests called "The Friends of Jesus", characterized by a deep spirituality and special vows (for example the vow of poverty). He had also an apostolic activity amongst Chinese students.

  12. A magnified young galaxy from about 500 million years after the Big Bang.

    Science.gov (United States)

    Zheng, Wei; Postman, Marc; Zitrin, Adi; Moustakas, John; Shu, Xinwen; Jouvel, Stephanie; Høst, Ole; Molino, Alberto; Bradley, Larry; Coe, Dan; Moustakas, Leonidas A; Carrasco, Mauricio; Ford, Holland; Benítez, Narciso; Lauer, Tod R; Seitz, Stella; Bouwens, Rychard; Koekemoer, Anton; Medezinski, Elinor; Bartelmann, Matthias; Broadhurst, Tom; Donahue, Megan; Grillo, Claudio; Infante, Leopoldo; Jha, Saurabh W; Kelson, Daniel D; Lahav, Ofer; Lemze, Doron; Melchior, Peter; Meneghetti, Massimo; Merten, Julian; Nonino, Mario; Ogaz, Sara; Rosati, Piero; Umetsu, Keiichi; van der Wel, Arjen

    2012-09-20

    Re-ionization of the intergalactic medium occurred in the early Universe at redshift z ≈ 6-11, following the formation of the first generation of stars. Those young galaxies (where the bulk of stars formed) at a cosmic age of less than about 500 million years (z ≲ 10) remain largely unexplored because they are at or beyond the sensitivity limits of existing large telescopes. Understanding the properties of these galaxies is critical to identifying the source of the radiation that re-ionized the intergalactic medium. Gravitational lensing by galaxy clusters allows the detection of high-redshift galaxies fainter than what otherwise could be found in the deepest images of the sky. Here we report multiband observations of the cluster MACS J1149+2223 that have revealed (with high probability) a gravitationally magnified galaxy from the early Universe, at a redshift of z = 9.6 ± 0.2 (that is, a cosmic age of 490 ± 15 million years, or 3.6 per cent of the age of the Universe). We estimate that it formed less than 200 million years after the Big Bang (at the 95 per cent confidence level), implying a formation redshift of ≲14. Given the small sky area that our observations cover, faint galaxies seem to be abundant at such a young cosmic age, suggesting that they may be the dominant source for the early re-ionization of the intergalactic medium.

  13. Cosmology as Relativistic Particle Mechanics: From Big Crunch to Big Bang

    CERN Document Server

    Russo, J G

    2004-01-01

    Cosmology can be viewed as geodesic motion in an appropriate metric on an `augmented' target space; here we obtain these geodesics from an effective relativistic particle action. As an application, we find some exact (flat and curved) cosmologies for models with N scalar fields taking values in a hyperbolic target space for which the augmented target space is a Milne universe. The singularities of these cosmologies correspond to points at which the particle trajectory crosses the Milne horizon, suggesting a novel resolution of them, which we explore via the Wheeler-deWitt equation.

  14. From First Stars to the Spite Plateau: a Possible Reconciliation of Halo Stars Observations with Predictions from Big Bang Nucleosynthesis

    CERN Document Server

    Piau, L; Beers, T C; Ferguson, J W; Sivarani, T; Truran, J W

    2006-01-01

    Since the pioneering observations of Spite & Spite in 1982, the constant lithium abundance of metal-poor ([Fe/H]<-1.3) halo stars near the turnoff has been attributed a cosmological origin. Closer analysis revealed that the observed abundance lies at $\\Delta$ Li~0.4 dex below the predictions of Big Bang Nucleosynthesis. The measurements of deuterium abundances on the lines of sight toward quasars and the recent data from the Wilkinson Microwave Anisotropy Probe independently confirmed this gap. We suggest here that part of the discrepancy is explained by the first generation of stars that efficiently depleted lithium. Assuming that the models for lithium evolution in the halo turnoff stars and $\\Delta$ Li estimates are correct, we infer that between 1/3 and 1/2 of the baryonic matter of the early halo (~10^9 Mo) was processed through Population III stars. This new paradigm proposes a very economical solution to the lingering difficulty of understanding the properties of the Spite Plateau and its lack o...

  15. A revised thermonuclear rate of $^{7}$Be($n$,$\\alpha$)$^{4}$He relevant to Big-Bang nucleosynthesis

    CERN Document Server

    Hou, S Q; Kubono, S; Chen, Y S

    2015-01-01

    In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The $^7$Be($n$,$\\alpha$)$^4$He reaction, which may affect the $^7$Li abundance, was regarded as the secondary important reaction in destructing the $^7$Be nucleus in BBN. However, the thermonuclear rate of $^7$Be($n$,$\\alpha$)$^4$He has not been well studied so far. This reaction rate was firstly estimated by Wagoner in 1969, which has been generally adopted in the current BBN simulations and the reaction rate library. This simple estimation involved only a direct-capture reaction mechanism, but the resonant contribution should be also considered according to the later experimental results. In this work, we have revised this rate based on the indirect cross-section data available for the $^4$He($\\alpha$,$n$)$^7$Be and $^4$He($\\alpha$,$p$)$^7$Li reactions, with the charge symmetry and deta...

  16. Origin of matter and space-time in the big bang

    Energy Technology Data Exchange (ETDEWEB)

    Mathews, G. J. [University of Notre Dame, Center for Astrophysics/JINA, Notre Dame, IN 46556, USA and Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Kajino, T. [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yamazaki, D. [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Kusakabe, M. [School of Liberal Arts and Science, Korea Aerospace University, Goyang 412-791, Korea and Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of)

    2014-05-02

    We review the case for and against a bulk cosmic motion resulting from the quantum entanglement of our universe with the multiverse beyond our horizon. Within the current theory for the selection of the initial state of the universe from the landscape multiverse there is a generic prediction that pre-inflation quantum entanglement with other universes should give rise to a cosmic bulk flow with a correlation length of order horizon size and a velocity field relative to the expansion frame of the universe. Indeed, the parameters of this motion are are tightly constrained. A robust prediction can be deduced indicating that there should be an overall motion of of about 800 km/s relative to the background space time as defined by the cosmic microwave background (CMB). This talk will summarize the underlying theoretical motivation for this hypothesis. Of course our motion relative to the background space time (CMB dipole) has been known for decades and is generally attributed to the gravitational pull of the local super cluster. However, this cosmic peculiar velocity field has been recently deduced out to very large distances well beyond that of the local super cluster by using X-ray galaxy clusters as tracers of matter motion. This is achieved via the kinematic component of the Sunyaev-Zeldovich (KSZ) effect produced by Compton scattering of cosmic microwave background photons from the local hot intracluster gas. As such, this method measures peculiar velocity directly in the frame of the cluster. Similar attempts by our group and others have attempted to independently assess this bulk flow via Type la supernova redshifts. In this talk we will review the observation case for and against the existence of this bulk flow based upon the observations and predictions of the theory. If this interpretation is correct it has profound implications in that we may be observing for the first time both the physics that occurred before the big bang and the existence of the multiverse

  17. Origin of matter and space-time in the big bang

    Science.gov (United States)

    Mathews, G. J.; Kajino, T.; Yamazaki, D.; Kusakabe, M.; Cheoun, M.-K.

    2014-05-01

    We review the case for and against a bulk cosmic motion resulting from the quantum entanglement of our universe with the multiverse beyond our horizon. Within the current theory for the selection of the initial state of the universe from the landscape multiverse there is a generic prediction that pre-inflation quantum entanglement with other universes should give rise to a cosmic bulk flow with a correlation length of order horizon size and a velocity field relative to the expansion frame of the universe. Indeed, the parameters of this motion are are tightly constrained. A robust prediction can be deduced indicating that there should be an overall motion of of about 800 km/s relative to the background space time as defined by the cosmic microwave background (CMB). This talk will summarize the underlying theoretical motivation for this hypothesis. Of course our motion relative to the background space time (CMB dipole) has been known for decades and is generally attributed to the gravitational pull of the local super cluster. However, this cosmic peculiar velocity field has been recently deduced out to very large distances well beyond that of the local super cluster by using X-ray galaxy clusters as tracers of matter motion. This is achieved via the kinematic component of the Sunyaev-Zeldovich (KSZ) effect produced by Compton scattering of cosmic microwave background photons from the local hot intracluster gas. As such, this method measures peculiar velocity directly in the frame of the cluster. Similar attempts by our group and others have attempted to independently assess this bulk flow via Type la supernova redshifts. In this talk we will review the observation case for and against the existence of this bulk flow based upon the observations and predictions of the theory. If this interpretation is correct it has profound implications in that we may be observing for the first time both the physics that occurred before the big bang and the existence of the multiverse

  18. Engine of life and big bang of evolution: a personal perspective.

    Science.gov (United States)

    Barber, James

    2004-01-01

    Photosystem II (PS II) is the engine for essentially all life on our planet and its beginning 2.5 billion years ago was the 'big bang of evolution.' It produces reducing equivalents for making organic compounds on an enormous scale and at the same time provides us with an oxygenic atmosphere and protection against UV radiation (in the form of the ozone layer). In 1967, when I began my career in photosynthesis research, little was known about PS II. The Z-scheme had been formulated [Hill and Bendall (1960) Nature 186: 136-137] and Boardman and Anderson [(1964) Nature 203: 166-167] had isolated PS II as a discrete biochemical entity. PS II was known not only to be the source of oxygen but of variable chlorophyll fluorescence [Duysens and Sweers (1963) In: Studies on Microalgae and Photosynthetic Bacteria, pp. 353-372. University of Tokyo Press, Tokyo] and delayed chlorophyll fluorescence [Arnold and Davidson (1954) J Gen Physiol 37: 677-684]. P680 had just been discovered [Döring et al. (1967) Z Naturforsch 22b: 639-644]. No wonder the 'black box of PS II' was described at that time by Bessel Kok and George Cheniae [Current Topics in Bioenergetics 1: 1-47 (1966)] as the 'inner sanctum of photosynthesis.' What a change in our level of understanding of PS II since then! The contributions of many talented scientists have unraveled the mechanisms and structural basis of PS II function and we are now very close to revealing the molecular details of the remarkable and thermodynamically demanding reaction which it catalyzes, namely the splitting of water into its elemental constituents. It has been a privilege to be involved in this journey.

  19. Conference | The Big Bang and the interfaces of knowledge: towards a common understanding of Truth? | 25 June

    CERN Multimedia

    2014-01-01

    You are cordially invited to attend the concluding open session of the conference The Big Bang and the interfaces of knowledge: towards a common understanding of Truth?    Wednesday 25 June at 14.30 in the Main Auditorium Please register by Tuesday 24 June at: https://indico.cern.ch/event/325739/ In 2012, CERN and Wilton Park hosted the pioneering international conference “The Big Bank and the interfaces of knowledge: towards a common language?” The purpose of this conference was to enable scientists from a range of disciplines to dialogue with philosophers and theologians from the world religions about the nature of the Big Bang. What understandings might scientists and theologians share in common? How are their paradigms shaped and developed? Is it possible to develop a common framework or language. The conference gained global attention. A follow-up conference will be held on 23-25 June 2014 with the purpose of widening the spectrum of...

  20. A Study of the Subtitle Translation in “The Big Bang Theory” from Newmark’s Communicative Translation Theory

    Institute of Scientific and Technical Information of China (English)

    甄宽; 彭念凡; 甄顺

    2015-01-01

    The subtitle translation is very different from other forms of translation.We translators should meet the particular needs of the subtitle.This study is going to analyze the subtitle translation in "The Big Bang Theory" from Newmark’s Communicative Translation Theory in three main perspectives:the information transmission,the aesthetics effect and the emotional transmission.In the information transmission the study will put emphasis on the limited circumstance.In the aesthetics effect the study will explore the expression of the sense of beauty.In the emotional transmission this study will study the use of rhetoric to express different emotions.

  1. A Study of the Subtitle Translation in“The Big Bang Theory”from Newmark’s Communicative Translation Theory

    Institute of Scientific and Technical Information of China (English)

    甄宽; 彭念凡; 甄顺

    2015-01-01

    The subtitle translation is very different from other forms of translation.We translators should meet the particular needs of the subtitle.This study is going to analyze the subtitle translation in“The Big Bang Theory” from Newmark’s Communicative Translation Theory in three main perspectives:the information transmission,the aesthetics effect and the emotional transmission.In the information transmission the study will put emphasis on the limited circumstance.In the aesthetics effect the study will explore the expression of the sense of beauty.In the emotional transmission this study will study the use of rhetoric to express different emotions.

  2. Codimension-Two Big-Bang Bifurcation in a ZAD-Controlled Boost DC-DC Converter

    Science.gov (United States)

    Amador, A.; Casanova, S.; Granada, H. A.; Olivar, G.; Hurtado, J.

    In this paper, we study some nonlinear behaviors in a two-dimensional system defined by a Boost Converter controlled by CPWM (Centered Pulse-Width Modulation) and a ZAD (Zero Average Dynamics) strategy. The dynamics was analyzed using a discrete-time map, which consists of a sampled system at each switching cycle. The structure of the two-parametric space is characterized analytically. This allows proving the existence and stability of an infinite number of codimension-one curves that intersect at the same point in the two-parametric space. This phenomenon has been called a big-bang bifurcation.

  3. Constraint on Heavy Element Production in Inhomogeneous Big-Bang Nucleosynthesis from The Light-Element Observations

    CERN Document Server

    Nakamura, Riou; Fujimoto, Shin-ichiro; Sato, Katsuhiko

    2013-01-01

    We investigate the observational constraints on the inhomogeneous big-bang nucleosynthesis that Matsuura et al. suggested the possibility of the heavy element production beyond ${}^7$Li in the early universe. From the observational constraints on light elements of ${}^4$He and D, possible regions are found on the plane of the volume fraction of the high density region against the ratio between high-and low-density regions. In these allowed regions, we have confirmed that the heavy elements beyond Ni can be produced appreciably, where $p$- and/or $r$-process elements are produced well simultaneously.

  4. 'Big Bang' tomography as a new route to atomic-resolution electron tomography.

    Science.gov (United States)

    Van Dyck, Dirk; Jinschek, Joerg R; Chen, Fu-Rong

    2012-06-13

    Until now it has not been possible to image at atomic resolution using classical electron tomographic methods, except when the target is a perfectly crystalline nano-object imaged along a few zone axes. The main reasons are that mechanical tilting in an electron microscope with sub-ångström precision over a very large angular range is difficult, that many real-life objects such as dielectric layers in microelectronic devices impose geometrical constraints and that many radiation-sensitive objects such as proteins limit the total electron dose. Hence, there is a need for a new tomographic scheme that is able to deduce three-dimensional information from only one or a few projections. Here we present an electron tomographic method that can be used to determine, from only one viewing direction and with sub-ångström precision, both the position of individual atoms in the plane of observation and their vertical position. The concept is based on the fact that an experimentally reconstructed exit wave consists of the superposition of the spherical waves that have been scattered by the individual atoms of the object. Furthermore, the phase of a Fourier component of a spherical wave increases with the distance of propagation at a known 'phase speed'. If we assume that an atom is a point-like object, the relationship between the phase and the phase speed of each Fourier component is linear, and the distance between the atom and the plane of observation can therefore be determined by linear fitting. This picture has similarities with Big Bang cosmology, in which the Universe expands from a point-like origin such that the distance of any galaxy from the origin is linearly proportional to the speed at which it moves away from the origin (Hubble expansion). The proof of concept of the method has been demonstrated experimentally for graphene with a two-layer structure and it will work optimally for similar layered materials, such as boron nitride and molybdenum disulphide.

  5. Gravitino, dark matter candidate and implications for big bang nucleosynthesis; Le gravitino, candidat a la matiere noire et les implications en nucleosynthese primordiale

    Energy Technology Data Exchange (ETDEWEB)

    Bailly, S

    2008-11-15

    The Standard Model of particle physics was developed in the seventies. Despite many experimental successes, it presents many problems that can only be solved with models beyond the Standard Model. Supersymmetry is an interesting candidate, postulating a new symmetry between fermions and bosons. This model can also have interesting applications in cosmology. It offers potentially good candidates for dark matter, what represents 25% of the energy density of the Universe, and its nature is unknown. Another cosmological problem is the lithium problems in Big Bang Nucleosynthesis describing the production of light elements in the first seconds of the Universe. The lithium abundance predicted by the theory is inconsistent with observations. I study a scenario in which a supersymmetric particle, the gravitino, is the candidate for dark matter and the production of this particle through the decay of other supersymmetric particles may solve the lithium problems. (author)

  6. The 7Be(d,p)2alpha cross section at Big Bang energies and the primordial 7Li abundance

    CERN Document Server

    Angulo, C; Couder, M; Demaret, P; Leleux, P; Vanderbist, F; Coc, A; Kiener, J; Tatischeff, V; Davinson, T; Murphy, A S; Achouri, N L; Orr, N A; Cortina-Gil, D; Figuera, P; Fulton, B R; Mukha, I; Vangioni, E

    2005-01-01

    The WMAP satellite, devoted to the observations of the anisotropies of the Cosmic Microwave Background (CMB) radiation, has recently provided a determination of the baryonic density of the Universe with unprecedented precision. Using this, Big Bang Nucleosynthesis (BBN) calculations predict a primordial 7Li abundance which is a factor 2-3 higher than that observed in galactic halo dwarf stars. It has been argued that this discrepancy could be resolved if the 7Be(d,p)2alpha reaction rate is around a factor of 100 larger than has previously been considered. We have now studied this reaction, for the first time at energies appropriate to the Big Bang environment, at the CYCLONE radioactive beam facility at Louvain-la-Neuve. The cross section was found to be a factor of 10 smaller than derived from earlier measurements. It is concluded therefore that nuclear uncertainties cannot explain the discrepancy between observed and predicted primordial 7Li abundances, and an alternative astrophysical solution must be inve...

  7. Big Bang, inflation, standard Physics… and the potentialities of new Physics and alternative cosmologies. Present statuts of observational and experimental Cosmology. Open questions and potentialities of alternative cosmologies

    Science.gov (United States)

    Gonzalez-Mestres, Luis

    2016-11-01

    A year ago, we wrote [1] that the field of Cosmology was undergoing a positive and constructive crisis. The possible development of more direct links between the Mathematical Physics aspects of cosmological patterns and the interpretation of experimental and observational results was particularly emphasized. Controversies on inflation are not really new, but in any case inflation is not required in pre-Big Bang models and the validity of the standard Big Bang + inflation + ΛCDM pattern has not by now been demonstrated by data. Planck has even explicitly reported the existence of "anomalies". Remembering the far-reaching work of Yoichiro Nambu published in 1959-61, it seems legitimate to underline the need for a cross-disciplinary approach in the presence of deep, unsolved theoretical problems concerning new domains of matter properties and of the physical world. The physics of a possible preonic vacuum and the associated cosmology constitute one of these domains. If the vacuum is made of superluminal preons (superbradyons), and if standard particles are vacuum excitations, how to build a suitable theory to describe the internal structure of such a vacuum at both local and cosmic level? Experimental programs (South Pole, Atacama, AUGER, Telescope Array…) and observational ones (Planck, JEM-EUSO…) devoted to the study of cosmic microwave background radiation (CMB) and of ultra-high energy cosmic rays (UHECR) are crucial to elucidate such theoretical interrogations and guide new phenomenological developments. Together with a brief review of the observational and experimental situation, we also examine the main present theoretical and phenomenological problems and point out the role new physics and alternative cosmologies can potentially play. The need for data analyses less focused a priori on the standard models of Particle Physics and Cosmology is emphasized in this discussion. An example of a new approach to both fields is provided by the pre-Big Bang pattern

  8. "Big Bang'' as a result of first-order phase transition driven by changing scalar curvature in expanding early Universe: "hyperinflation'' scenario

    CERN Document Server

    Pashitskii, E A

    2015-01-01

    We suggest that the "Big Bang" may be a result of the first-order phase transition driven by changing scalar curvature of the 4D space-time in expanding cold Universe, filled with nonlinear scalar field $\\phi $ and neutral matter with equation of state $p=\

  9. 多模态下情景喜剧The Big Bang Theory的字幕翻译

    Institute of Scientific and Technical Information of China (English)

    王祥冰

    2010-01-01

    本文在多模态话语分析的理论框架下,探讨最近流行的美国电视情景喜剧The Big Bang Theory的字幕翻译方法,分析在新的观看方式和特殊的文化环境下,字幕与画面、音响等其他模态之问的关系比传统的辅助作用要更深入,直译的方式能更好发挥字幕的作用,使得该情景喜剧的"幽默交际"得以成功实现.

  10. The Big Bang and Its Proofs%宇宙大爆炸:有什么证据?

    Institute of Scientific and Technical Information of China (English)

    白杉

    2003-01-01

    @@ 大爆炸理论是关于宇宙形成的最有影响的一种学说,英文说法为Big Bang,也称为大爆炸宇宙论.大爆炸理论诞生于20世纪20年代,在40年代得到补充和发展,但一直寂寂无闻.直到50年代,人们才开始广泛注意这个理论.大爆炸理论的主要观点是认为我们的宇宙诞生于140亿年前,并曾有一段从热到冷的演化史.迄今人类已经获得的宇宙大爆炸证据有下列内容.

  11. Criticize the Big-bang Cosmology%“大爆炸宇宙学”批评

    Institute of Scientific and Technical Information of China (English)

    黄志洵

    2015-01-01

    the big-bang cosmogony was based on the Hubble’ s astro-observation,he discovered that the remote celestial bodies are leaving far from us. It is the Hubble’ s theory of expanding cosmography. But this theory lacks sufficient proof,then it should be a product of subjective idealism. Another important argument of the theory of exploded cosmogony is that measurement data on microwave background radia-tion,but the data can’ t indicate that the temperature of microwave background radiation should be the re-sult of once exploding. It is never the spread ember at once exploding of an original celestrial body. Ac-cording to the definity of cosmos,people can’ t say “the age of cosmos”,because we only can say “the age of earth”,“the age of solar system” and“the age of star system”;etc. Then,we are against these ab-surd views of big-bang cosmology categorically,because such theoretical system is full of flaws that both science and philosophy all can’ t hold. Although it seems that the universe is riddled with in explicable forces,the theory of dark matter and dark energy just are two hypothesises. Another hypothesis is the exist of gravitational waves,it is just an estimate,but the actual situation might be different. The velocity of gravity in Newton’ s universal law is infinite,but the gravity propagation speed and the velocity of gravitational waves in Einstein’ s theory are the light speed c. The General relativity( GR) explains these features by suggesting that gravitation ( un-like electromagnetic forces) is a pure geometric effect of curved space-time,not a force of nature that propagates. Moreover,now different gravity models need to be considered. For example,if gravity is once again taken to be a propagating force of nature in flat space-time with the propagation speed indicated by observational evidence and experiments:not less than 2 × 1010c(c is the speed of light in vacuum). Al-though faster-than-light force propagation speeds do

  12. How to analyse a Big Bang of data: the mammoth project at the Cern physics laboratory in Geneva to recreate the conditions immediately after the universe began requires computing power on an unprecedented scale

    CERN Multimedia

    Thomas, Kim

    2005-01-01

    How to analyse a Big Bang of data: the mammoth project at the Cern physics laboratory in Geneva to recreate the conditions immediately after the universe began requires computing power on an unprecedented scale

  13. 基于粒子群优化的混合宇宙大爆炸算法%Hybrid Big Bang-Big Crunch Algorithm Based on Particle Swarm Optimization

    Institute of Scientific and Technical Information of China (English)

    吴伟民; 田龙; 林志毅

    2016-01-01

    宇宙大爆炸算法( Big Bang-Big Crunch,BB-BC)思想来源于宇宙大爆炸和大收缩理论。针对其在高维函数的寻优过程中,随迭代次数增加,爆炸生成的碎片解收缩速度慢,多样性快速减弱,质量变差,容易陷入局部最优解的缺点,提出一种混合型BB-BC算法( HBB-BC)。首先,将质心代入当代解中作为奇点解进行改进,提高算法收缩速度;其次,结合粒子群优化的路径优化,提高碎片解的质量;最后,引入宇宙大撕裂理论增加大爆炸阶段碎片解的多样性和跳出局部最优解的能力。通过9个新型测试函数进行测试,测试结果显示,HBB-BC算法在高维函数的寻优性能上更优于BB-BC算法和另一种改进的均匀大爆炸混沌大收缩( UBB-CBC)算法。%The Big Bang-Big Crunch ( BB-BC ) algorithm is based on the big bang and big contraction theory of the universe. With the increase of number of iterations in optimizing of high dimensional func-tions, the candidates shrink slowly, worsen in quality and weaken rapidly in diversity, as well as sink in-to a local optimal solution. In light of these features, an improved hybrid BB-BC algorithm ( HBB-BC) is proposed. This algorithm puts the center of mass into contemporary candidates computing as a singular point solution to increase the speed of contraction and improves the candidates’ quality and enhances its diversity by mean of Particle Swarm optimization (PSO). At last, Big Rip theory is introduced to in-crease the diversity of the big bang phase solutions and the ability to jump out of local optimal solution. The experimental results tested by 9 new benchmark test functions indicate that the improved algorithm performs better than the BB-BC and Uniform Big Bang-Chaotic Big Crunch ( UBB-CBC) on optimization of high dimensional functions.

  14. Large hadron collider will get us closer to the Big Bang

    CERN Multimedia

    Khadilkar, Dhananjay

    2006-01-01

    The LHC consists of a 27 km tunnel located 100 meters under the ground near Geneva in Switzerland, lined with hundreds of superconducting magnets which will accelerate protons and subsequently collide them at mind-boggling energies of 14 terra electorn Volts. The result will be conditions prevalent just microseconds after the Big Band 15 billion years ago (1/2 page)

  15. Bid to recreate the Big Bang and unlock the secrets of life hits a

    CERN Multimedia

    Morgan, James

    2007-01-01

    "It was not the kind of "big band" they were hopint for - but the explosion at the new £6.81 bn particle accelerator in Switzerland on Saturday, was "not a major setback", says a British scientist who is leading the project." (1 page)

  16. Big bang nucleosynthesis and the cosmic neutrino background%大爆炸核合成与宇宙背景中微子

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    We present a brief overview of the neutrino decoupling and big bang nucleosynthe-sis in the early universe. The big bang relic neutrinos formed one of the backgrounds of the universe.A few possible ways to directly detect the cosmic neutrino background are briefly introduced, and partic-ular attention is paid to the relic neutrino capture on b-decaying nuclei.%  文章基于大爆炸宇宙学描述了发生于宇宙早期的中微子退耦与轻核素合成事件。退耦后的中微子形成宇宙的背景之一。文章介绍了几种探测宇宙背景中微子的方法,侧重于利用b衰变核俘获超低动能的中微子。

  17. Historia del modelo cosmológico estándar LCDM: la cosmología física tras del modelo del big bang

    OpenAIRE

    2015-01-01

    Desde que el big bang se asentara como modelo cosmológico estándar han pasado 50 años. En este periodo, la cosmología ha mantenido abierta la cuestión de cuál es la evolución del universo y a través de la teoría inflacionaria ha enfrentado el p

  18. The biological big bang: the first oceans of primordial planets at 2-8 million years explain Hoyle/Wickramasinghe cometary panspermia

    Science.gov (United States)

    Gibson, Carl H.

    2011-10-01

    Hydrogravitional-dynamics (HGD) cosmology of Gibson/Schild 1996 predicts that the primordial H-He4 gas of big bang nucleosynthesis became proto-globular-star-cluster clumps of Earth-mass planets at 300 Kyr. The first stars formed from mergers of these 3000 K gas planets. Chemicals C, N, O, Fe etc. created by stars and supernovae then seeded many of the reducing hydrogen gas planets with oxides to give them hot water oceans with metallic iron-nickel cores. Water oceans at critical temperature 647 K then hosted the first organic chemistry and the first life, distributed to the 1080 planets of the cosmological big bang by comets produced by the new (HGD) planet-merger star formation mechanism. The biological big bang scenario occurs between 2 Myr when liquid oceans condensed and 8 Myr when they froze. HGD cosmology explains, very naturally, the Hoyle/Wickramasinghe concept of cometary panspermia by giving a vast, hot, nourishing, cosmological primordial soup for abiogenesis, and the means for transmitting the resulting life forms and their evolving chemical mechanisms widely throughout the universe. A primordial astrophysical basis is provided for astrobiology by HGD cosmology. Concordance ΛCDMHC cosmology is rendered obsolete by the observation of complex life on Earth.

  19. The Biological Big Bang: The First Oceans of Primordial Planets at 2-8 Million Years Explain Hoyle/Wickramasinghe Cometary Panspermia

    CERN Document Server

    Gibson, Carl H

    2011-01-01

    Hydrogravitional-dynamics (HGD) cosmology of Gibson/Schild 1996 predicts that the primordial H-He^4 gas of big bang nucleosynthesis became proto-globular-star-cluster clumps of Earth-mass planets at 300 Kyr. The first stars formed from mergers of these 3000 K gas planets. Chemicals C, N, O, Fe etc. created by stars and supernovae then seeded many of the reducing hydrogen gas planets with oxides to give them hot water oceans with metallic iron-nickel cores. Water oceans at critical temperature 647 K then hosted the first organic chemistry and the first life, distributed to the 10^80 planets of the cosmological big bang by comets produced by the new (HGD) planet-merger star formation mechanism. The biological big bang scenario occurs between 2 Myr when liquid oceans condensed and 8 Myr when they froze. HGD cosmology explains, very naturally, the Hoyle/Wickramasinghe concept of cometary panspermia by giving a vast, hot, nourishing, cosmological primordial soup for abiogenesis, and the means for transmitting the ...

  20. The Biological Big Bang: The First Oceans of Primordial Planets at 2-8 Myr Explains Hoyle-Wickramasinghe Cometary Panspermia and a Primordial LUCA

    Science.gov (United States)

    Gibson, Carl H.; Wickramasinghe, N. C.; Schild, R. E.

    2011-10-01

    Hydrogravitional-dynamics (HGD) cosmology of Gibson/Schild 1996 predicts that the primordial H-He4 gas of big bang nucleosynthesis became proto-globular-star-cluster clumps of Earth-mass planets at 300 Kyr. The first stars formed from mergers of these 3000 K gas planets. Chemicals C, N, O, Fe etc. created by stars and supernovae then seeded many of the reducing hydrogen gas planets with oxides to give them hot water oceans with metallic iron-nickel cores. Water oceans at critical temperature 647 K then hosted the first organic chemistry and the first life, distributed to the 1080 planets of the cosmological big bang by comets produced by the new (HGD) planet-merger star formation mechanism. The biological big bang scenario occurs between 2 Myr when liquid oceans condensed and 8 Myr when they froze. HGD cosmology explains, very naturally, the Hoyle/Wickramasinghe concept of cometary panspermia by giving a vast, hot, nourishing, cosmological primordial soup for abiogenesis, and the means for transmitting the resulting life forms and their evolving chemical mechanisms widely throughout the universe from the resulting RNA last-universal-common-ancestor LUCA. A primordial astrophysical basis is provided for astrobiology by HGD cosmology. Concordance ΛCDMHC cosmology is rendered obsolete by the observation of complex life on Earth.

  1. Hydro-gravitational-dynamics cosmology is crucial to astrobiology and the biological big bang at two million years

    Science.gov (United States)

    Gibson, Carl H.

    2015-09-01

    Hydro-Gravitational-Dynamics (HGD) cosmology predicts that the 1012 s (30 Kyr) H-He4 plasma protogalaxies become, by viscous fragmentation, proto-globular-star-cluster PGC clumps of a trillion small planets, at the 1013 s transition to gas. Larger planets and stars result from mergers of these hot 3000 K hydrogen planets in the PGCs. Stardust oxides of life chemicals C, N, O, Fe, Si seed the planets when the stars explode as supernovae. Hydrogen reduces the metal oxides and silicates to metal and rocky planet cores with massive hot water oceans at critical water temperature 647 K in which organic chemistry and life can develop. Because information is continually exchanged between the merging planets, they form a cosmic soup. The biological big bang occurs between 2 Myr when liquid water rains hot deep oceans in the cooling cosmos, and 8 Myr when the oceans freeze6. Thus, HGD cosmology explains the Hoyle/Wickramasinghe concept of cometary panspermia by giving a vast, hot, nourishing, cosmological primordial soup for abiogenesis, and the means for transmitting the resulting life forms and their evolving RNA/DNA mechanisms widely throughout the universe. A primordial astrophysical basis is provided for astrobiology by HGD cosmology. Concordance ΛCDMHC cosmology is rendered obsolete by the observation of complex life on Earth.

  2. A Rapidly Star-forming Galaxy 700 Million Years After the Big Bang at z=7.51

    CERN Document Server

    Finkelstein, S L; Dickinson, M; Song, M; Tilvi, V; Koekemoer, A M; Finkelstein, K D; Mobasher, B; Ferguson, H C; Giavalisco, M; Reddy, N; Ashby, M L N; Dekel, A; Fazio, G G; Fontana, A; Grogin, N A; Huang, J -S; Kocevski, D; Rafelski, M; Weiner, B J; Willner, S P

    2013-01-01

    Out of several dozen z > 7 candidate galaxies observed spectroscopically, only five have been confirmed via Lyman-alpha emission, at z=7.008, 7.045, 7.109, 7.213 and 7.215. The small fraction of confirmed galaxies may indicate that the neutral fraction in the intergalactic medium (IGM) rises quickly at z > 6.5, as Lyman-alpha is resonantly scattered by neutral gas. However, the small samples and limited depth of previous observations makes these conclusions tentative. Here we report the results of a deep near-infrared spectroscopic survey of 43 z > 6.5 galaxies. We detect only a single galaxy, confirming that some process is making Lyman-alpha difficult to detect. The detected emission line at 1.0343 um is likely to be Lyman-alpha emission, placing this galaxy at a redshift z = 7.51, an epoch 700 million years after the Big Bang. This galaxy's colors are consistent with significant metal content, implying that galaxies become enriched rapidly. We measure a surprisingly high star formation rate of 330 Msol/yr,...

  3. Effect of exotic long-lived sub-strongly interacting massive particles in big bang nucleosynthesis and a new solution to the Li problem

    Directory of Open Access Journals (Sweden)

    Kawasaki Masahiro

    2012-02-01

    Full Text Available The plateau of 7Li abundance as a function of the iron abundance by spectroscopic observations of metal-poor halo stars (MPHSs indicates its primordial origin. The observed abundance levels are about a factor of three smaller than the primordial 7Li abundance predicted in the standard Big Bang Nucleosynthesis (BBN model. This discrepancy might originate from exotic particle and nuclear processes operating in BBN epoch. Some particle models include heavy (m >> 1 GeV long-lived colored particles which would be confined inside exotic heavy hadrons, i.e., strongly interacting massive particles (SIMPs. We have found reactions which destroy 7Be and 7Li during BBN in the scenario of BBN catalyzed by a long-lived sub-strongly interacting massive particle (sub-SIMP, X. The reactions are non radiative X captures of 7 Be and 7Li which can be operative if the X particle interacts with nuclei strongly enough to drive 7 Be destruction but not strongly enough to form a bound state with 4 He of relative angular momentum L = 1. We suggest that 7Li problem can be solved as a result of a new process beyond the standard model through which the observable signature was left on the primordial Li abundance.

  4. High-energy break-up of 6Li as a tool to study the Big-Bang nucleosynthesis reaction 2H(alpha,gamma)6Li

    CERN Document Server

    Hammache, F; Typel, S; Galaviz, D; Sümmerer, K; Coc, A; Uhlig, F; Attallah, F; Caamano, M; Cortina, D; Geissel, H; Hellström, M; Iwasa, N; Kiener, J; Koczon, P; Kohlmeyer, B; Mohr, P; Schwab, E; Schwarz, K; Schümann, F; Senger, P; Sorlin, O; Tatischeff, V; Thibaud, J P; Vangioni, E; Wagner, A; Walus, W

    2010-01-01

    The recently claimed observations of non-negligible amounts of 6Li in old halo stars have renewed interest in the Big-Bang Nucleosynthesis (BBN) of 6Li. One important ingredient in the predicted BBN abundance of 6Li is the low-energy 2H(alpha,gamma)6Li cross section. Up to now, the only available experimental result for this cross section showed an almost constant astrophysical S-factor below 400 keV, contrary to theoretical expectations. We report on a new measurement of the 2H(alpha,gamma)6Li reaction using the break-up of 6Li at 150 A MeV. Even though we cannot separate experimentally the Coulomb contribution from the nuclear one, we find clear evidence for Coulomb-nuclear interference by analyzing the scattering-angular distributions. This is in-line with our theoretical description which indicates a drop of the S_24-factor at low energies as predicted also by most other models. Consequently, we find even lower upper limits for the calculated primordial 6Li abundance than before.

  5. THE ANATOMY OF AN EXTREME STARBURST WITHIN 1.3 Gyr OF THE BIG BANG REVEALED BY ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Carilli, C. L. [National Radio Astronomy Observatory, P.O. Box 0, Socorro, NM 87801 (United States); Riechers, D. [Astronomy Department, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Walter, F. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Maiolino, R.; Lentati, L. [Astrophysics Group, Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Wagg, J. [European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19 (Chile); McMahon, R. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Wolfe, A., E-mail: ccarilli@aoc.nrao.edu [Department of Physics and Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093 (United States)

    2013-02-15

    We present further analysis of the [C II] 158 {mu}m fine structure line and thermal dust continuum emission from the archetype extreme starburst/active galactic nucleus (AGN) group of galaxies in the early universe, BRI 1202-0725 at z = 4.7, using the Atacama Large Millimeter Array. The group has long been noted for having a closely separated (26 kpc in projection) FIR-hyperluminous quasar host galaxy and an optically obscured submillimeter galaxy (SMG). A short ALMA test observation reveals a rich laboratory for the study of the myriad processes involved in clustered massive galaxy formation in the early universe. Strong [C II] emission from the SMG and the quasar have been reported earlier by Wagg et al. based on these observations. In this paper, we examine in more detail the imaging results from the ALMA observations, including velocity channel images, position-velocity plots, and line moment images. We present detections of [C II] emission from two Ly{alpha}-selected galaxies in the group, demonstrating the relative ease with which ALMA can detect the [C II] emission from lower star formation rate galaxies at high redshift. Imaging of the [C II] emission shows a clear velocity gradient across the SMG, possibly indicating rotation or a more complex dynamical system on a scale {approx}10 kpc. There is evidence in the quasar spectrum and images for a possible outflow toward the southwest, as well as more extended emission (a {sup b}ridge{sup )}, between the quasar and the SMG, although the latter could simply be emission from Ly{alpha}-1 blending with that of the quasar at the limited spatial resolution of the current observations. These results provide an unprecedented view of a major merger of gas-rich galaxies driving extreme starbursts and AGN accretion during the formation of massive galaxies and supermassive black holes within 1.3 Gyr of the big bang.

  6. Enhancing Teachers' Awareness About Relations Between Science and Religion. The Debate Between Steady State and Big Bang Theories

    Science.gov (United States)

    Bagdonas, Alexandre; Silva, Cibelle Celestino

    2015-11-01

    Educators advocate that science education can help the development of more responsible worldviews when students learn not only scientific concepts, but also about science, or "nature of science". Cosmology can help the formation of worldviews because this topic is embedded in socio-cultural and religious issues. Indeed, during the Cold War period, the cosmological controversy between Big Bang and Steady State theory was tied up with political and religious arguments. The present paper discusses a didactic sequence developed for and applied in a pre-service science teacher-training course on history of science. After studying the historical case, pre-service science teachers discussed how to deal with possible conflicts between scientific views and students' personal worldviews related to religion. The course focused on the study of primary and secondary sources about cosmology and religion written by cosmologists such as Georges Lemaître, Fred Hoyle and the Pope Pius XII. We used didactic strategies such as short seminars given by groups of pre-service teachers, videos, computer simulations, role-play, debates and preparation of written essays. Along the course, most pre-service teachers emphasized differences between science and religion and pointed out that they do not feel prepared to conduct classroom discussions about this topic. Discussing the relations between science and religion using the history of cosmology turned into an effective way to teach not only science concepts but also to stimulate reflections about nature of science. This topic may contribute to increasing students' critical stance on controversial issues, without the need to explicitly defend certain positions, or disapprove students' cultural traditions. Moreover, pre-service teachers practiced didactic strategies to deal with this kind of unusual content.

  7. A galaxy rapidly forming stars 700 million years after the Big Bang at redshift 7.51.

    Science.gov (United States)

    Finkelstein, S L; Papovich, C; Dickinson, M; Song, M; Tilvi, V; Koekemoer, A M; Finkelstein, K D; Mobasher, B; Ferguson, H C; Giavalisco, M; Reddy, N; Ashby, M L N; Dekel, A; Fazio, G G; Fontana, A; Grogin, N A; Huang, J-S; Kocevski, D; Rafelski, M; Weiner, B J; Willner, S P

    2013-10-24

    Of several dozen galaxies observed spectroscopically that are candidates for having a redshift (z) in excess of seven, only five have had their redshifts confirmed via Lyman α emission, at z = 7.008, 7.045, 7.109, 7.213 and 7.215 (refs 1-4). The small fraction of confirmed galaxies may indicate that the neutral fraction in the intergalactic medium rises quickly at z > 6.5, given that Lyman α is resonantly scattered by neutral gas. The small samples and limited depth of previous observations, however, makes these conclusions tentative. Here we report a deep near-infrared spectroscopic survey of 43 photometrically-selected galaxies with z > 6.5. We detect a near-infrared emission line from only a single galaxy, confirming that some process is making Lyman α difficult to detect. The detected emission line at a wavelength of 1.0343 micrometres is likely to be Lyman α emission, placing this galaxy at a redshift z = 7.51, an epoch 700 million years after the Big Bang. This galaxy's colours are consistent with significant metal content, implying that galaxies become enriched rapidly. We calculate a surprisingly high star-formation rate of about 330 solar masses per year, which is more than a factor of 100 greater than that seen in the Milky Way. Such a galaxy is unexpected in a survey of our size, suggesting that the early Universe may harbour a larger number of intense sites of star formation than expected.

  8. Big Bounce Singularity of a Simple Five-Dimensional Cosmological Model

    Institute of Scientific and Technical Information of China (English)

    徐立昕; 刘宏亚; 王贝利

    2003-01-01

    The big bounce singularity of a simple five-dimensional cosmological model is studied. Contrary to the standard big bang space-time singularity, this big bounce singularity is found to be an event horizon at which the scale factor and the mass density of the universe are finite, while the pressure undergoes a sudden transition from negative infinity to positive infinity. By using coordinate transformation it is also shown that before the bounce the universe contracts deflationary. According to the proper-time, the universe may have existed for an infinitely long time.

  9. The first three minutes - 1990 version. [of early universe after Big Bang

    Science.gov (United States)

    Schramm, David N.

    1991-01-01

    The present state of understanding of what occurred in the universe's first three minutes is reviewed. Emphasis is on the events that lead to potentially observable consequences and that are model-independent or at least generic to broad classes of models. Inflation, phase transitions, dark matter, and nucleosynthesis are summarized.

  10. The Biological Big Bang: The First Oceans of Primordial Planets at 2-8 Million Years Explain Hoyle/Wickramasinghe Cometary Panspermia

    OpenAIRE

    Carl H. Gibson

    2011-01-01

    Hydrogravitional-dynamics (HGD) cosmology of Gibson/Schild 1996 predicts that the primordial H-He^4 gas of big bang nucleosynthesis became proto-globular-star-cluster clumps of Earth-mass planets at 300 Kyr. The first stars formed from mergers of these 3000 K gas planets. Chemicals C, N, O, Fe etc. created by stars and supernovae then seeded many of the reducing hydrogen gas planets with oxides to give them hot water oceans with metallic iron-nickel cores. Water oceans at critical temperature...

  11. Galaxy formation from annihilation-generated supersonic turbulence in the baryon-symmetric big-bang cosmology and the gamma ray background spectrum

    Science.gov (United States)

    Stecker, F. W.; Puget, J. L.

    1972-01-01

    Following the big-bang baryon symmetric cosmology of Omnes, the redshift was calculated to be on the order of 500-600. It is show that, at these redshifts, annihilation pressure at the boundaries between regions of matter and antimatter drives large scale supersonic turbulence which can trigger galaxy formation. This picture is consistent with the gamma-ray background observations discussed previously. Gravitational binding of galaxies then occurs at a redshift of about 70, at which time vortical turbulent velocities of about 3 x 10 to the 7th power cm/s lead to angular momenta for galaxies comparable with measured values.

  12. Testing the Big Bang: Light elements, neutrinos, dark matter and large-scale structure

    Science.gov (United States)

    Schramm, David N.

    1991-01-01

    Several experimental and observational tests of the standard cosmological model are examined. In particular, a detailed discussion is presented regarding: (1) nucleosynthesis, the light element abundances, and neutrino counting; (2) the dark matter problems; and (3) the formation of galaxies and large-scale structure. Comments are made on the possible implications of the recent solar neutrino experimental results for cosmology. An appendix briefly discusses the 17 keV thing and the cosmological and astrophysical constraints on it.

  13. Mach Cones and Hydrodynamic Flow:. Probing Big Bang Matter in the Laboratory

    Science.gov (United States)

    Betz, Barbara; Rau, Philip; Stöcker, Horst

    A critical discussion of the present signals for the phase transition to quark-gluon plasma (QGP) is given. Since hadronic rescattering models predict much larger flow than observed from 1 to 50 A GeV laboratory bombarding energies, this observation is interpreted as potential evidence for a first-order phase transition at high baryon density. A detailed discussion of the collective flow as a barometer for the equation of state (EoS) of hot dense matter at RHIC follows. Here, hadronic rescattering models can explain 2 GeV/c. This is interpreted as an evidence for the production of superdense matter at RHIC. The connection of v2 to jet suppression is examined. A study of Mach shocks generated by fast partonic jets propagating through the QGP is given. The main goal is to take into account different types of collective motion during the formation and evolution of this matter. A significant deformation of Mach shocks in central Au+Au collisions at RHIC and LHC energies as compared to the case of jet propagation in a static medium is predicted. A new hydrodynamical study of jet energy loss is presented.

  14. Mach Cones and Hydrodynamic Flow Probing Big Bang Matter in the Laboratory

    CERN Document Server

    Betz, Barbara; Stöcker, Horst

    2007-01-01

    A critical discussion of the present signals for the phase transition to quark-gluon plasma (QGP) is given. Since hadronic rescattering models predict much larger flow than observed from 1 to 50 A GeV laboratory bombarding energies, this observation is interpreted as potential evidence for a first-order phase transition at high baryon density. A detailed discussion of the collective flow as a barometer for the equation of state (EoS) of hot dense matter at RHIC follows. Here, hadronic rescattering models can explain $ 2$ GeV/c. This is interpreted as an evidence for the production of superdense matter at RHIC. The connection of $v_2$ to jet suppression is examined. A study of Mach shocks generated by fast partonic jets propagating through the QGP is given. The main goal is to take into account different types of collective motion during the formation and evolution of this matter. A significant deformation of Mach shocks in central Au+Au collisions at RHIC and LHC energies as compared to the case of jet propag...

  15. The Anatomy of an Extreme Starburst within 1.3 Gyr of the Big Bang Revealed by ALMA

    Science.gov (United States)

    Carilli, C. L.; Riechers, D.; Walter, F.; Maiolino, R.; Wagg, J.; Lentati, L.; McMahon, R.; Wolfe, A.

    2013-02-01

    We present further analysis of the [C II] 158 μm fine structure line and thermal dust continuum emission from the archetype extreme starburst/active galactic nucleus (AGN) group of galaxies in the early universe, BRI 1202-0725 at z = 4.7, using the Atacama Large Millimeter Array. The group has long been noted for having a closely separated (26 kpc in projection) FIR-hyperluminous quasar host galaxy and an optically obscured submillimeter galaxy (SMG). A short ALMA test observation reveals a rich laboratory for the study of the myriad processes involved in clustered massive galaxy formation in the early universe. Strong [C II] emission from the SMG and the quasar have been reported earlier by Wagg et al. based on these observations. In this paper, we examine in more detail the imaging results from the ALMA observations, including velocity channel images, position-velocity plots, and line moment images. We present detections of [C II] emission from two Lyα-selected galaxies in the group, demonstrating the relative ease with which ALMA can detect the [C II] emission from lower star formation rate galaxies at high redshift. Imaging of the [C II] emission shows a clear velocity gradient across the SMG, possibly indicating rotation or a more complex dynamical system on a scale ~10 kpc. There is evidence in the quasar spectrum and images for a possible outflow toward the southwest, as well as more extended emission (a "bridge"), between the quasar and the SMG, although the latter could simply be emission from Lyα-1 blending with that of the quasar at the limited spatial resolution of the current observations. These results provide an unprecedented view of a major merger of gas-rich galaxies driving extreme starbursts and AGN accretion during the formation of massive galaxies and supermassive black holes within 1.3 Gyr of the big bang. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA

  16. The rapid formation of a large rotating disk galaxy three billion years after the Big Bang.

    Science.gov (United States)

    Genzel, R; Tacconi, L J; Eisenhauer, F; Schreiber, N M Förster; Cimatti, A; Daddi, E; Bouché, N; Davies, R; Lehnert, M D; Lutz, D; Nesvadba, N; Verma, A; Abuter, R; Shapiro, K; Sternberg, A; Renzini, A; Kong, X; Arimoto, N; Mignoli, M

    2006-08-17

    Observations and theoretical simulations have established a framework for galaxy formation and evolution in the young Universe. Galaxies formed as baryonic gas cooled at the centres of collapsing dark-matter haloes; mergers of haloes and galaxies then led to the hierarchical build-up of galaxy mass. It remains unclear, however, over what timescales galaxies were assembled and when and how bulges and disks--the primary components of present-day galaxies--were formed. It is also puzzling that the most massive galaxies were more abundant and were forming stars more rapidly at early epochs than expected from models. Here we report high-angular-resolution observations of a representative luminous star-forming galaxy when the Universe was only 20% of its current age. A large and massive rotating protodisk is channelling gas towards a growing central stellar bulge hosting an accreting massive black hole. The high surface densities of gas, the high rate of star formation and the moderately young stellar ages suggest rapid assembly, fragmentation and conversion to stars of an initially very gas-rich protodisk, with no obvious evidence for a major merger.

  17. First direct measurement of the 2H(α,γ)6Li cross section at big bang energies and the primordial lithium problem.

    Science.gov (United States)

    Anders, M; Trezzi, D; Menegazzo, R; Aliotta, M; Bellini, A; Bemmerer, D; Broggini, C; Caciolli, A; Corvisiero, P; Costantini, H; Davinson, T; Elekes, Z; Erhard, M; Formicola, A; Fülöp, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Gyürky, Gy; Junker, M; Lemut, A; Marta, M; Mazzocchi, C; Prati, P; Rossi Alvarez, C; Scott, D A; Somorjai, E; Straniero, O; Szücs, T

    2014-07-25

    Recent observations of (6)Li in metal poor stars suggest a large production of this isotope during big bang nucleosynthesis (BBN). In standard BBN calculations, the (2)H(α,γ)(6)Li reaction dominates (6)Li production. This reaction has never been measured inside the BBN energy region because its cross section drops exponentially at low energy and because the electric dipole transition is strongly suppressed for the isoscalar particles (2)H and α at energies below the Coulomb barrier. Indirect measurements using the Coulomb dissociation of (6)Li only give upper limits owing to the dominance of nuclear breakup processes. Here, we report on the results of the first measurement of the (2)H(α,γ)(6)Li cross section at big bang energies. The experiment was performed deep underground at the LUNA 400 kV accelerator in Gran Sasso, Italy. The primordial (6)Li/(7)Li isotopic abundance ratio has been determined to be (1.5 ± 0.3) × 10(-5), from our experimental data and standard BBN theory. The much higher (6)Li/(7)Li values reported for halo stars will likely require a nonstandard physics explanation, as discussed in the literature.

  18. Big-Bang-Gate Cosmic Titanic: Why Aren't Physics Journal's Editors Bringing It To The Center of Scientific Attention

    Science.gov (United States)

    Gentry, Robert

    2010-02-01

    Until now science's greatest debacle occurred when Copernicus exposed Ptolemaic cosmologists' 1300 hundred year-long fraud that it must be true because observations fit theory so well, while they ignored the untested state of its central assumption of Earth centered planetary motion. With much hubris modern physicists are confident this could never happen again, that the integrity of physics journals editors suffices to guarantee that a challenge to the reigning cosmological theory -- big bang cosmology -- would immediately be brought to the center of scientific attention for analysis and discussion. In fact a decade ago it was reported [MPLA 2619 (1997); arXiv:gr-gc/9806061] that, like Ptolemaic cosmology before it, big bang's central assumption that GR expansion effects cause in-flight expansion had never been tested and, further, that experimental testing of it using GR operation of the GPS showed it to be false. This result proves it is impossible for the 2.73 K CBR to be fireball relic radiation. These results were expanded in CERN reports EXT-2003-021;022, but have been uniformly rejected by physics journals, one of which accepted a paper similar to CERN EXT-2003-022, only to reject it a few days later with the admission not to publish it because of fearing reaction of the worldwide physics community. For update on my PRL submission see http://www.alphacosmos.net. )

  19. The Big Bang machine

    CERN Multimedia

    Cox, Brian

    2009-01-01

    "At Cern in Geneva, 10'000 scientists form all over the world have gathered to discover the secrets of the universe. We drove there in a new Volvo C30 to watch the preparations for the second switch on" (12 pages)

  20. Clash over Big Bang

    CERN Multimedia

    Hawkes, N

    1999-01-01

    A recent announcement from Fermilab that they had discovered a precise value for the degree of CP Violation, has angered scientists at CERN who say the 'new' result is simply confirmation of results gained at CERN eleven years ago (1 page).

  1. Jupiter's Big Bang.

    Science.gov (United States)

    McDonald, Kim A.

    1994-01-01

    Collision of a comet with Jupiter beginning July 16, 1994 will be observed by astronomers worldwide, with computerized information relayed to a center at the University of Maryland, financed by the National Aeronautics and Space Administration and National Science Foundation. Geologists and paleontologists also hope to learn more about earth's…

  2. Big Bang launch

    CERN Document Server

    2008-01-01

    Physicists from the University, along with scientists and engineers around the world, watched with fevered anticipation as the world's biggest scientific experiment was launched in September. (1/1 page)

  3. Finding the Big Bang

    Science.gov (United States)

    Peebles, P. James E.; Page, Lyman A., Jr.; Partridge, R. Bruce

    2009-03-01

    1. Introduction; 2. A guide to modern cosmology; 3. Origins of the cosmology of the 1960s; 4. Recollections of the 1960s Dave Hogg, Neville Woolf, George B. Field, Patrick Thaddeus, Donald E. Osterbrock, Yuri Nikolaevich Smirnov, Igor Dmitriyevich Novikov, Andrei Georgievich Doroshkevich, Rashid Alievich Sunyaev, Malcolm S. Longair, Arno Penzias, Robert W. Wilson, Bernard F. Burke, Kenneth C. Turner, P. James E. Peebles, David T. Wilkinson, Peter G. Roll, R. Bruce Partridge, Malcolm S. Longair, John Faulkner, Robert V. Wagoner, Martin Rees, Geoffrey R. Burbidge, Jayant V. Narlikar, David Layzer, Michele Kaufman, Jasper V. Wall, John Shakeshaft, William Welch, Kazimir S. Stankevich, Paul Boynton, Robert A. Stokes, Martin Harwit, Judith L. Pipher, Kandiah Shivanandan, Rainer Weiss, Jer-tsang Yu, Rainer K. Sachs, Arthur M. Wolfe, Joe Silk, George F. R. Ellis, Ronald N. Bracewell, Edward K. Conklin, Stephen Boughn, Karl C. Davis, Paul S. Henry; 5. Cosmology and the CMBR since the 1960s Dick Bond; Appendixes; Glossary; References; Index.

  4. The analysis of irony through relevance theory in the big bang theory sitcom = A análise da ironia por meio da teoria da relevância na comédia de situação the big bang theory

    Directory of Open Access Journals (Sweden)

    Izaias, Karla Camila Oliveira

    2011-01-01

    Full Text Available Neste trabalho, será analisada a teoria da relevância proposta por Sperber e Wilson. Adicionalmente, a figura de linguagem ironia será descrita. Esse referencial teórico será utilizado para analisar um episódio da comédia de situação intitulado "The Big Bang Theory", em um esforço para demonstrar como enunciados são compreendidos entre os personagens e o público e como ironia é largamente utilizada como recurso humorístico

  5. The analysis of irony through relevance theory in the big bang theory sitcom = A análise da ironia por meio da teoria da relevância na comédia de situação the big bang theory

    OpenAIRE

    2011-01-01

    Neste trabalho, será analisada a teoria da relevância proposta por Sperber e Wilson. Adicionalmente, a figura de linguagem ironia será descrita. Esse referencial teórico será utilizado para analisar um episódio da comédia de situação intitulado "The Big Bang Theory", em um esforço para demonstrar como enunciados são compreendidos entre os personagens e o público e como ironia é largamente utilizada como recurso humorístico

  6. Innovación empresarial y desarrollo económico: De la destrucción creativa al big bang social coordinado

    Directory of Open Access Journals (Sweden)

    Carmen González Marsal

    2015-09-01

    Full Text Available El presente artículo parte de la distinción de Schumpeter entre innovación e invención en función de sus consecuencias económicas y analiza su conocido concepto de destrucción creativa provocada por la innovación empresarial. A continuación, se centra en el decisivo efecto de armonización social del ejercicio de la empresarialidad, sugiriendo la superación del concepto schumpeteriano a través de la idea de la creatividad coordinadora. De esta forma, se comprende que la innovación empresarial en vez de conducir a la autodestrucción del capitalismo, hace posible el desarrollo económico y social de manera ilimitada, proceso que ha sido denominado big bang social coordinado.

  7. An Analysis of Humor of the Big Bang Theory (Season Six)%《生活大爆炸》第六季的幽默探析

    Institute of Scientific and Technical Information of China (English)

    邬贝贝; 潘文红

    2014-01-01

    This paper analyzes humor of The Big Bang Theory (Season Six) from the perspective of violation of the cooperative principle .The study helps enable English learners to have a better understanding of Grice ’ s cooperative principle and enhance their appreciation of English humor in situation comedies .%以《生活大爆炸》第六季的对话为语料,从违反合作原则的角度出发,探讨会话者因违反合作原则的四个准则而产生的幽默效果,从而加强英语学习者对格莱斯会话含义理论的理解,提高对情景喜剧中英语幽默的欣赏能力。

  8. 功能目的论视角下情景喜剧字幕翻译研究——以The Big Bang Theory为例

    Institute of Scientific and Technical Information of China (English)

    房晶

    2011-01-01

    德国功能主义目的论在行为理论、语篇语言学和交际理论的基础上,提出了翻译目的决定翻译策略,将译者从直译还是意译的两难处境中解放出来,增加了可供选择的翻译策略,为译者灵活处理源语文本提供了理论依据。本文以美国情景喜剧The Big Bang Theory为例,分别从目的论的"目的原则"、"连贯原则"和"忠诚原则"三方面,分析了该剧字幕的翻译方法和策略。

  9. Feynman Clocks, Casual Networks, and the Origin of Hierarchical "Arrows of Time" in Complex Systems from the Big Bang to the Brain

    CERN Document Server

    Hitchcock, S M

    2000-01-01

    A theory of 'time' as a form of 'information' is proposed. New tools such as Feynman Clocks, Collective Excitation Networks, Sequential Excitation Networks, Plateaus of Complexity, Causal Networks, and Quantum Computation methods are used to unify previously separate 'arrows of time'. The 'direction' and 'dimension' of 'time' are found to be secondary information structures created by the 'processing' of the information carried by signals connecting 'clocks' together in networks. The 'problem of time' may be solved by identification of a fundamental 'irreversible' Quantum Arrow of Time and 'reversible' Classical Arrows of Time. These 'arrows' can used to map information flow through complex causal networks from the Big Bang to the Brain. Keywords; unification of the fundamental interactions of matter, consciousness, entangled states, time reversal, time travel, and FTL or superluminal signals

  10. Empirical Determination of Bang-Bang Operations

    CERN Document Server

    Byrd, M S; Byrd, Mark S.; Lidar, Daniel A.

    2003-01-01

    Strong and fast "bang-bang" (BB) pulses have been recently proposed as a means for reducing decoherence in a quantum system. So far theoretical analysis of the BB technique relied on model Hamiltonians. Here we introduce a method for empirically determining the set of required BB pulses, that relies on quantum process tomography. In this manner an experimenter may tailor his or her BB pulses to the quantum system at hand, without having to assume a model Hamiltonian.

  11. The Study of Pedantic Language in the Big Bang Theory%《生活大爆炸》中学究语研究

    Institute of Scientific and Technical Information of China (English)

    王亚辉

    2014-01-01

    Variants vary via variable communities. Social dialect reflects in distinct speech communities caused by social factors. Pedantic language, a sort of academic style used by speech communities with high education background, is a language variety stylized with advanced terminologies and complex sentences. The TV The Big Bang Theory, with its unique script setting, cate-gorizes its dialogues into pedantic language. Its plays discernibly incarnate the use of pedantic language in specific registers, and dis-play the impacts of it with other varieties of speech communities to some extent. This paper tentatively studies the influence of ac-ademic style on inappropriate registers through the corpus of season two of The Big Bang Theory.%语言变体随社会网络变化而迥异。社群言语的抽象表现就是由社会因素造成的社会方言。“学究语”是受教育程度相当高的社会团体使用的学术性语体,话语中常包含高级术语和复杂长句,是语言变体的一种。美剧《生活大爆炸》中独特地剧本背景设定将角色语言划归为学究语,在不同程度上表现出学究语作为独特的语言变体在特定语域中的作用,以及与不同社群的其他语言变体的冲突。该文对该剧第二季语料中的语言变体进行分析,试解读固定语域下非恰当语体对听话人造成的影响。

  12. Model Development Industrial Cluster Coffee Arabica in The District Bangli, Province of Bali

    Directory of Open Access Journals (Sweden)

    I Gusti Bagus Udayana

    2015-04-01

    Full Text Available Indonesian coffee commodity is non-oil export commodities the which contributes to the increase of in foreign exchange. The coffee agribusiness development Efforts have been undertaken by the government, but there are still many obstacles, especially in maintaining the quality of products that meet international market standards and continuity of production in accordance with market demand and to support a downstream industry of agricultural production. This research is the development of industrial clusters Earlier research arabica coffee. The results Showed that the human resources and knowledge about the importance of the coffee plant in Bangli society is still very low, this is evidenced by the many farmers replacing the coffee with citrus plants. Cluster models produced is the result of the development of the models on previous research. In the development of this models and the results of the field survey results show the need for forming FGD Control of Agro-Industry Forum Bangli. This forum Aimed to control and anticipate the development of information to replace the coffee plant with coffee other than agricultural industrial commodities like oranges. Many coffee farmers have replaced coffee with citrus plants. If this continues to Happen it is feared that coffee production has gained International recognition will Decrease. This controller Bangli Agro-Industry Forum in collaboration with Industrial Cluster Management Communication Forum Coffee Arabica and core industry of arabica coffee

  13. Big Bangs in Galaxy Clusters: Using X-ray Temperature Maps to Trace Merger Histories in Clusters with Radio Halos/Relics

    Science.gov (United States)

    Burns, Jack O.; Datta, Abhirup; Hallman, Eric J.

    2016-06-01

    Galaxy clusters are assembled through large and small mergers which are the most energetic events ("bangs") since the Big Bang. Cluster mergers "stir" the intracluster medium (ICM) creating shocks and turbulence which are illuminated by ~Mpc-sized radio features called relics and halos. These shocks heat the ICM and are detected in x-rays via thermal emission. Disturbed morphologies in x-ray surface brightness and temperatures are direct evidence for cluster mergers. In the radio, relics (in the outskirts of the clusters) and halos (located near the cluster core) are also clear signposts of recent mergers. Our recent ENZO cosmological simulations suggest that around a merger event, radio emission peaks very sharply (and briefly) while the x-ray emission rises and decays slowly. Hence, a sample of galaxy clusters that shows both luminous x-ray emission and radio relics/halos are good candidates for very recent mergers. We are in the early stages of analyzing a unique sample of 48 galaxy clusters with (i) known radio relics and/or halos and (ii) significant archival x-ray observations (>50 ksec) from Chandra and/or XMM. We have developed a new x-ray data analysis pipeline, implemented on parallel processor supercomputers, to create x-ray surface brightness, high fidelity temperature, and pressure maps of these clusters in order to study merging activity. The temperature maps are made using three different map-making techniques: Weighted Voronoi Tessellation, Adaptive Circular Binning, and Contour Binning. In this talk, we will show preliminary results for several clusters, including Abell 2744 and the Bullet cluster. This work is supported by NASA ADAP grant NNX15AE17G.

  14. 宇舶Big Bang Unico系列10周年高级珠宝手表

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    宇舶是第一个将贵金属与天然橡胶融合的手表,2005年革命性地推出BigBang系列,一经推出就囊括了业界多个大奖。距离当初的初露锋芒,已经过去十年,这是宇舶为2015年巴塞尔钟表展推出的三款Big Bang系列手表的其中一种款式。

  15. The big bang of hemofiltration: the beginning of a new era in the third millennium for extra-corporeal blood purification!

    Science.gov (United States)

    Honore', P M; Joannes-Boyau, O; Merson, L; Boer, W; Piette, V; Galloy, A-C; Janvier, G

    2006-07-01

    Since the last decade, hemofiltration and especially high volume hemofiltration has rapidly evolved from a somewhat experimental treatment towards a potentially effective 'adjunctive' therapy in severe septic shock and especially refractory or catecholamine resistant hypodynamic septic shock. Nevertheless, this approach lacks prospective randomized studies (PRT'S) evaluating the critical role of early hemofiltration in sepsis. An important step forward which could be called the 'big bang' in term of hemofiltration was the publication of a PRT in patients with acute renal failure (ARF) (1). Before this study (2), nobody believed that hemofiltration could change the survival rate in intensive care. Since that big bang, many physicians consider that hemofiltration at a certain dose can change the survival rate in intensive care. So the world of hemofiltration in ICU is not a definitive world, it is still in expansion. Indeed, we now have to try to define what will be the exact dose we need in septic acute renal failure. This dose might well be 'higher' than 35 ml/kg/hour in the septic acute renal failure 'group' as suggested by many studies (2-5). At present, it is the issue of continuous dose of high volume hemofiltration that has to be tested in future randomized studies. Since the Vicenza study (2) has shown that 35 ml/kg/h is the best dose in terms of survival, dealing with non septic acute renal failure in ICU, several studies from different groups have shown that, in septic acute renal failure, a higher dose might correlate with better survival. This has also been shown in some way by the study of the 'Vicenza group' but not with a statistically significant value (2). New PRT'S have just started in Europe like the IVOIRE study (hIgh VOlume in Intensive caRE) (6) and the RENAL study. Another large study is looking more basically at dose in non septic acute renal failure in Australasia and is led by the group of Rinaldo Bellomo in Melbourne (7) as well as the ATN

  16. Big Bang and bucks set to collide in inner space The price of exploring inner space went up this week

    CERN Multimedia

    Overbye, Dennis

    2007-01-01

    "At a news conference in Beijing this Thursday, an international consortium of physicists released the first detailed design of what they believe will be the Next Big Thing in physics: a machine 20 miles long that will slam together electrons and their evil-twin opposites, positrons, to produce fireballs of energy recreating conditions when the universe was only a trillionth of a second old." (1.5 page)

  17. 从合作原则分析《The Big Bang Theory》经典对白之幽默

    Institute of Scientific and Technical Information of China (English)

    向丽梅; 黎晓凤

    2015-01-01

    在交际中,为了保证会话的顺利进行,语用学中的合作原则要求交谈双方都必须遵守一些基本准则以期获得交际成功。但人们有时会故意违反合作原则中的某条或某几条准则,目的是想表达一定的会话含义,而这时幽默就会产生。本文以美国热播情景喜剧《The Big Bang Theory》典型对白为例,逐条分析其幽默产生机制,以期英语学习者能更好地理解合作原则,欣赏蕴藏在这些对白中的幽默。一、引言对幽默的研究实际上是对幽默的解读——幽默是怎么

  18. 将美剧引入高职英语课堂促进跨文化意识培养--以The Big Bang Theory为例

    Institute of Scientific and Technical Information of China (English)

    王梦君

    2015-01-01

    语言学习的最终目标是进行交际,学习者只在语言学层面学习语言,而缺乏跨文化意识,并不能够达到此目标。英语非母语国家的英语教学普遍存在的问题之一,是对英语学习者缺乏充分的跨文化意识输入和培养。传媒的全球化发展为语言教学者提供了一个很好的媒介来解决这一问题。The Big Bang Theory是广受国内大学生喜爱的美剧之一,全剧节奏明快,语言精炼地道,场景能够还原生活并有连续性,人物特征鲜明,将此剧引入课堂对学习者跨文化意识的输入和培养大有裨益。

  19. Characterization of big bang, a novel gene encoding for PDZ domain-containing proteins that are dynamically expressed throughout Drosophila development.

    Science.gov (United States)

    Kim, Sabrina Y; Renihan, Maia K; Boulianne, Gabrielle L

    2006-06-01

    PDZ (PSD-95, Discs-large, ZO-1) domain proteins often function as scaffolding proteins and have been shown to play important roles in diverse cellular processes such as the establishment and maintenance of cell polarity, and signal transduction. Here, we report the identification and cloning of a novel Drosophila melanogaster gene that is predicted to produce several different PDZ domain-containing proteins through alternative promoter usage and alternative splicing. This gene, that we have named big bang (bbg), was first identified as C96-GAL4, a GAL4 enhancer trap line that was generated in our lab. To further characterize bbg, its expression pattern was examined in ovaries, embryos, and late third instar larvae using UAS reporter gene constructs, in situ hybridization, or immunocytochemistry. In addition, the expression of alternatively spliced transcripts was examined in more detail using in situ hybridization. We find that during embryogenesis bbg is predominantly expressed in the developing gut, but it is also expressed in external sensory organs found in the epidermis. In the late third instar larva, bbg is expressed along the presumptive wing margin in the wing disc, broadly in the eye disc, and in other imaginal discs as well as in the brain. The expression patterns observed are dynamic and specific during development, suggesting that like other genes that encode for several different PDZ domain protein isoforms, bbg likely plays important roles in multiple developmental processes.

  20. Unsolved Mysteries of Science: A Mind-Expanding Journey through a Universe of Big Bangs, Particle Waves, and Other Perplexing Concepts

    Science.gov (United States)

    Malone, John

    2001-08-01

    A LIVELY EXPLORATION OF THE BIGGEST QUESTIONS IN SCIENCE How Did the Universe Begin? The Big Bang has been the accepted theory for decades, but does it explain everything? How Did Life on Earth Get Started? What triggered the cell division that started the evolutionary chain? Did life come from outer space, buried in a chunk of rock? What is Gravity? Newton's apple just got the arguments started, Einstein made things more complicated. Just how does gravity fit in with quantum theory? What Is the Inside of the Earth Like? What exactly is happening beneath our feet, and can we learn enough to help predict earthquakes and volcanic eruptions? How Do We Learn Language? Is language acquisition an inborn biological ability, or does every child have to start from scratch? Is There a Missing Link? The story of human evolution is not complete. In addition to hoaxes such as "Piltdown Man" and extraordinary finds such as "Lucy," many puzzles remain. What, in the end, do we mean by a "missing link"?

  1. ECM and Verbal Humor—Take Big Bang Theory as an Example%事件域认知模型与言语幽默——以美剧《生活大爆炸》为例

    Institute of Scientific and Technical Information of China (English)

    高文璐

    2012-01-01

      以王寅教授提出的事件域认知模型(ECM)为理论基础,从认知的角度对美国情景喜剧《生活大爆炸》中的言语幽默进行动态分析.ECM对言语幽默具有很强的解释力,通过ECM中的事件(Event)、行为/事体(A/B)、特征性或分类性特征(D/C)三个层面探究《生活大爆炸》中言语幽默产生的动态机制.%  Event-domain Cognitive Model (ECM), proposed by Chinese professor Wang Yin, is applied to dynamically the cog⁃nitive analysis of verbal humor in an American sitcom Big Bang Theory. It affords a strong explanatory power for the formation of verbal humor. The ECM theory tries to explore the dynamic mechanism of verbal humor on the EVENT, ACTION, BEING and D/C levels.

  2. From the Big Bang to the life in the primitive seas. (Spanish Title: Desde la Gran Explosión hasta la vida en los mares primitivos)

    Science.gov (United States)

    Esteban, S. B.

    Man has always wondered about the origins of humanity, life, and the world around him. The Earth crust is a vast and natural archive, and its rocks represent the pages of the most documented events in the geological past. These rocks hold large amounts of information about the Earth history, whose age is estimated to be 4,600 million years. Historical Geology seeks to bring together the knowledge of the origin of the Universe as well as the origin of Earth as a member of the Solar System. The Big Bang theory supposes that the Universe began with a huge explosion. In the Earth's history it is possible to differentiate the biological events from the physical ones. The physical events are geographical and environmental transformations. The biological events are related to life on Earth. There are evidences of biological processes back to 3,500 million years ago. At the beginning, the conditions on Earth were catastrophic and unstable. At this stage, the first signs of life were the molecules that started to take energy from the sunlight and the chemical products. It was not a simple accumulation of gradual biological forms, but was accompanied by episodic innovations that allowed increasing complexity and greater use of ecospace. Some of these innovations are shown by certain groups of primitive arthropods adapted to live in oxygen-poor, deep marine environments. These arthropods have been found in 500 million-year-old rocks in northwestern Argentina (provinces of Jujuy and La Rioja), indicating the presence of oxygen-poor seas in that region.

  3. Gabriele Veneziano : "La physique moderne doit dépasser Einstein et explorer l'avant-Big Bang"

    CERN Multimedia

    Deschamps, Pascale-Marie

    2004-01-01

    Interview with Gabriele Veneziana: in search of the infinitesimally small and infinitesimally large, the Standard Model of elementary particles and Einstein's general relativity are not enough to explain the universe. The "visible" matter predicted by the Standard Model represents only 5% of the energy of the Universe, the dark "invisible" matter constitutes 25 to 30%. Therefore 65 to 70 % of something else is missing. String theory calls into question all that one knows of the primordial universe formulated by the Standard Model (4 pages)

  4. A study on verbal humor in The Big Bang Theory from the perspective of relevance theory%从关联理论视角解读《生活大爆炸》中的言语幽默

    Institute of Scientific and Technical Information of China (English)

    陈丽玉

    2013-01-01

    本文运用关联理论解读美国情景喜剧《生活大爆炸》中的幽默对白,探讨言语幽默的产生机制,以期更好地理解和欣赏言语幽默。%The present paper aims to study verbal humor in the American sitcom The Big Bang Theory from a perspective of Relevance Theory with a purpose of summarizing the generating mechanism of verbal humor and providing suggestions for better appreciation of verbal humor.

  5. A constraint on a varying proton--electron mass ratio 1.5 billion years after the Big Bang

    CERN Document Server

    Bagdonaite, J; Murphy, M T; Whitmore, J B

    2015-01-01

    A molecular hydrogen absorber at a lookback time of 12.4 billion years, corresponding to 10$\\%$ of the age of the universe today, is analyzed to put a constraint on a varying proton--electron mass ratio, $\\mu$. A high resolution spectrum of the J1443$+$2724 quasar, which was observed with the Very Large Telescope, is used to create an accurate model of 89 Lyman and Werner band transitions whose relative frequencies are sensitive to $\\mu$, yielding a limit on the relative deviation from the current laboratory value of $\\Delta\\mu/\\mu=(-9.5\\pm5.4_{\\textrm{stat}} \\pm 5.3_{\\textrm{sys}})\\times 10^{-6}$.

  6. Constraint on a varying proton-electron mass ratio 1.5 billion years after the big bang.

    Science.gov (United States)

    Bagdonaite, J; Ubachs, W; Murphy, M T; Whitmore, J B

    2015-02-20

    A molecular hydrogen absorber at a lookback time of 12.4 billion years, corresponding to 10% of the age of the Universe today, is analyzed to put a constraint on a varying proton-electron mass ratio, μ. A high resolution spectrum of the J1443+2724 quasar, which was observed with the Very Large Telescope, is used to create an accurate model of 89 Lyman and Werner band transitions whose relative frequencies are sensitive to μ, yielding a limit on the relative deviation from the current laboratory value of Δμ/μ=(-9.5 ± 5.4(stat)± 5.3(syst))×10(-6).

  7. A universal, post Big-Bang Nucleo-synthesis, pre-Galactic, origin of the Lithium (Spite) Plateau

    CERN Document Server

    Ouyed, Rachid

    2012-01-01

    (Abridged abstract) We investigate the lithium plateau in the context of primordial dual-shock quark novae (dsQNe; i.e. a QN occurring a few days to a few weeks following the preceding SN explosion) going off in the wake of Pop. III stars. The neutron-rich relativistic QN ejecta leads to spallation of 56Ni processed in the ejecta of the preceding SN ejecta and thus to "iron impoverishment" of the primordial gas swept by dsQNe. We show that the generation of stars formed from fragmentation of pristine clouds swept-up by dsQNe acquire a metallicity with -7.5 2 (and up to [C/Fe] ~ 5) can be accounted for in our model for dsQNe with t_delay 10-11 days (i.e. [Fe/H] > -3). For shorter delays the temperature of the SN shell is too hot (> 2.5x10^6 K) for the spallated 7Li to survive. We find a corresponding 6Li plateau with 6Li/7Li < 0.3.

  8. Research on the Subtitle Translation of "The Big Bang Theory" from the Perspective of Functional Equivalence Theory%功能对等视角下《生活大爆炸》字幕翻译研究

    Institute of Scientific and Technical Information of China (English)

    蒋婷婷; 高圣兵

    2014-01-01

    "The Big Bang Theory"is a popular sitcom welcomed by a large audience. The features and limitations of the subtitles are fully showed in this sitcom, so the research can be done to this sitcom. In order to find out whether the subtitle translation have met the need of equivalence with different translating skills and methods and how they meet it, this paper presents a case study of American sitcom "The Big Bang Theory" within the framework of functionalism.%《生活大爆炸》是一个广受喜欢的情景喜剧。其字幕翻译中,包含了许多影视翻译的特征和制约因素,本文从语言和文体方面选取一些比较典型的对话片段,分析说明在翻译过程中是如何做到功能对等的,进而论证奈达的功能对等理论对字幕翻译具有实践性指导作用。

  9. Birmingham probes the Big Bang

    CERN Multimedia

    2007-01-01

    "The world's largest particle accelerator in Geneva is gearing up to begin work again. BBC Midlands Today science correspondent David Gregory went to see how scientists from the University of Birmingham are at the heart of trying to understand what makes our universe tick." (1 page)

  10. Big Bang Day : Physics Rocks

    CERN Multimedia

    Brian Cox; John Barrowman; Eddie Izzard

    2008-01-01

    Is particle physics the new rock 'n' roll? The fundamental questions about the nature of the universe that particle physics hopes to answer have attracted the attention of some very high profile and unusual fans. Alan Alda, Ben Miller, Eddie Izzard, Dara O'Briain and John Barrowman all have interests in this branch of physics. Brian Cox - CERN physicist, and former member of 90's band D:Ream, tracks down some very well known celebrity enthusiasts and takes a light-hearted look at why this subject can appeal to all of us.

  11. Did the big bang boil?

    CERN Multimedia

    Wilczek, Frank

    2006-01-01

    "Standard theories tell us that, at some point in the Universe's evolution, free quarks and gluons must have become bound together into the hadronic matter we see today. But was this transition abrupt or smooth?

  12. Retour vers le Big Bang

    CERN Multimedia

    Pentier, Olivier

    2007-01-01

    A laboratory from Grenoble participated in the building of LHC (Large Hadron Collider) at CERN. This particle accelerator, operational at the end of 2007, will help to understand how the universe was born. (1 page)

  13. Big Bang Day: Engineering Solutions

    CERN Multimedia

    Lyn Evans; Austin Ball; Jim Virdee; Adam Hart-Davis

    2008-01-01

    CERN's Large Hadron Collider is the most complicated scientific apparatus ever built. Many of the technologies it uses hadn't even been invented when scientists started building it. Adam Hart-Davis discovers what it takes to build the world's most intricate discovery machine.

  14. Scientists recreating the Big Bang

    CERN Multimedia

    Bagla, Pallava

    2007-01-01

    "Beneath the breathtaking alpine vineyards, work is on at a feverish pace to complete a machine nickmamed the "Lord of Rings". Otherwise called a particle accelerator, it will be switched on next summer." (1/2 page)

  15. Model "Big Five" personality and criminal behavior

    OpenAIRE

    Sánchez-Teruel, David; Profesor, Departamento de Psicología-Área de Psicología Social, Facultad de Humanidades y Ciencias de la Educación, España.; Robles-Bello, Mª Auxiliadora; Profesor, Departamento de Psicología-Área de Psicología Social, Facultad de Humanidades y Ciencias de la Educación, España.

    2013-01-01

    It reflect on the theoretical issues that currently versa Personality Psychology in general and antisocial or criminal behavior in particular. It discusses how the model can be used personality "Big Five" applied to the field of crime, and shows the variables that the literature presented as more predictive, through one of the most widely used assessment instruments at present. It currently advises finding, meeting points between the various existing theories, for that personality does not be...

  16. Del Big Bang al Big Bounce

    OpenAIRE

    2010-01-01

    39 transp.-- Presentación incluida entre las actividades de divulgación y comunicación social de la Semana de la Ciencia y la Tecnología en el CSIC (Consejo Superior de Investigaciones Científicas, Nov 2010)

  17. 情景喜剧《生活大爆炸》中双关语的妙用%The using of puns in magical sitcom "the big bang"

    Institute of Scientific and Technical Information of China (English)

    张帆

    2013-01-01

      the pun is a common rhetorical device in English, but plays a decisive role in the sitcom. The paper discusses the classification of the pun in the sitcom "the big bang", and rhetorical effect, show the rich connotation and the artistic charm, and to improve the understanding of pun and appreciate level.%  双关是英语中一种常见的修辞手法,但是却在情景喜剧中起着举足轻重的作用。本文探讨情景喜剧《生活大爆炸》中双关的分类,及其修辞效果,展现双关丰富内涵及艺术魅力,并提高读者对双关的理解和欣赏水平。

  18. 从英汉文化差异角度看2012年热播美剧Gossip Girl和The Big Bang Theory的字幕翻译

    Institute of Scientific and Technical Information of China (English)

    孟芸

    2013-01-01

    如今.不论电视剧还是电影领域,从美国引进的作品都占有重要一席。然而目前大部分中国人还不具备不依赖字幕直接欣赏英语片的能力,因此字幕翻译正日益受到影视爱好者和语言学习者的高度重视。本文主要从英汉文化差异看2012年热播关剧Gossip Girl和The Big Bang Theory的字幕翻译以及其对翻译策略选择的影响。

  19. Interpretation of Irony in the Big Bang Theory from the Perspective of Relevance%关联理论视角下《生活大爆炸》中的反语阐释

    Institute of Scientific and Technical Information of China (English)

    郑燕

    2013-01-01

    Irony study is drawing more and more attention from linguists. The basic claim in this article will be illustrated with these three prototypical cases by analyzing ironic utterances in the Big Bang Theory. The aim is to show how the relevance-theoret⁃ic framework of verbal irony describe and explain ironic communication in this comedy.%  反语研究正在受到越来越多语言学家的关注。此文将通过《生活大爆炸》里的三个典型的案例分析来阐释反语,其研究目的是研究关联理论如何描述和解释这部喜剧里的反语。

  20. Bang-Bang shortcut to adiabaticity in trapped ion quantum simulators

    Science.gov (United States)

    Yoshimura, Bryce; Balasubramanian, Shankar; Han, Shuyang; Freericks, James

    2016-05-01

    An experimental simulation can prepare a nontrivial ground state via an adiabatic process, however due to experimental constraints this process becomes more and more difficult as the number of ions increase. Instead, we model the bang-bang optimization protocol as a shortcut to adiabaticity in the ground-state preparation of an ion-trap-based quantum simulator. This well known technique in the quantum control community is simple to implement and can be applied without prior knowledge of the Hamiltonian. We apply the bang-bang optimization protocol to the transverse-field Ising model as simulated in a linear Paul trap. We compare our results to a transverse magnetic field that exponential decays and the locally adiabatic approach. The bang-bang protocol produces a significantly higher ground-state probability than the exponential ramp. Although the bang-bang protocol produces a somewhat lower ground-state probability than the locally adiabatic approach, the implementation of the bang-bang protocol is far more simple than the locally adiabatic approach. NSF PHY-1314295.

  1. Modelling the low-tar BIG process; Modellering af low-tar BIG processen

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Lars Henrik

    2002-09-15

    This report describes the possibilities of integrating a biomass gasifier in a combined heat and power plant. The purpose of the study is, among others, to see if the gasification technology can challenge existing heat and power production methods. A research programme dealing with the construction of a low far gasifier (LT-BIG), which easily can be scaled to large gasification plants, is in progress. This report also contains a model formulation and implementation for this suggested low tar gasifier. All the models are created by the use of the energy simulation tool DNA. For some cases it has been necessary to develop new components or to alter existing components in DNA. Three different systems are considered; Gas Engine, Simple Cycle Gas Turbine and Combined Cycle. When biomass with and lower heating value of 19 MJ/kg and a moisture content of 50% is employed the subsequent results and designs are achieved: 1) The Engine plant utilizes the hot flue-gas to dry the biomass, but has difficulties taking advantage of the potential energy from the cooling of the syngas. An engine with a net electric efficiency of 40% at full load is computed to convert 38,5% of the energy content in the biomass to electricity. 2) The Simple Cycle Gas Turbine plant has good potential for integration with a gasifier. It dries the biomass by means of the flue-gas and recuperates the energy from the hot syngas to preheat the pressurised gas before it enters the combustion chamber. With an isentropic efficiency of 89% and a pressure ratio of 20, an electric efficiency of 38% is computed. 3) The Combined Cycle plant almost reach a computed efficiency of 45%. It utilises the cooling of the hot syngas to produce extra steam for the cycle, which results in a very steady efficiency, even when the moisture content of the fuel is changed. A grand parametric and sensitivity study of the LT-BIG model is carried out. The study includes estimates of the air demand for the gasifier and the partial

  2. Modeling and Analysis in Marine Big Data: Advances and Challenges

    Directory of Open Access Journals (Sweden)

    Dongmei Huang

    2015-01-01

    Full Text Available It is aware that big data has gathered tremendous attentions from academic research institutes, governments, and enterprises in all aspects of information sciences. With the development of diversity of marine data acquisition techniques, marine data grow exponentially in last decade, which forms marine big data. As an innovation, marine big data is a double-edged sword. On the one hand, there are many potential and highly useful values hidden in the huge volume of marine data, which is widely used in marine-related fields, such as tsunami and red-tide warning, prevention, and forecasting, disaster inversion, and visualization modeling after disasters. There is no doubt that the future competitions in marine sciences and technologies will surely converge into the marine data explorations. On the other hand, marine big data also brings about many new challenges in data management, such as the difficulties in data capture, storage, analysis, and applications, as well as data quality control and data security. To highlight theoretical methodologies and practical applications of marine big data, this paper illustrates a broad view about marine big data and its management, makes a survey on key methods and models, introduces an engineering instance that demonstrates the management architecture, and discusses the existing challenges.

  3. SEPHIROT: SCENARIO for CREATION AUTOMATICALLY from DIGITS AVERAGED-PROBABILITY Newcomb-Benford Log-Law: Inflation, BosonS, a Maxwell-Boltzmann Big-Bang Fireball, FermionS, HDE, HDM, CMB; UTTER-SIMPLICITY PURPOSELY SANS ANYthing!!!: It's a Jack-in-the-Box Univers: A Consciousness? EMET/TRUTH!!!

    Science.gov (United States)

    Siegel, Edward Carl-Ludwig; Marvin Antonoff/Albert Overhauser(RIP)/Frederic Young/Adolph Smith/Irwin Wunderman(RIP/Janis Wignall Team

    2013-03-01

    Siegel[http://fqxi.org/community/forum/topic/1553]: TEN-DIGITS[0,...,9] PROBABILITY AVERAGE LOG-Law SCALE-INVARIANCE; Utter-Simplicity: ``Complexity'' (Versus ``Complicatedness'') Zipf-law/ Hyperbolicity/ Inevitability (Archimedes), vs, Pareto-law, SCENARIO AUTOMATICALLY CREATES a UNIVERSE: inflation, a big-bang, bosons(E) ->Mellin-(c⌃2)-tranform -> fermions (m) , hidden - dark - energy (HDE) , hidden - dark - matter (HDM) , cosmic-microwave-background(CMB), supersymmetry(SUSY) PURPOSELY SANS ANY: theories, models, mechanisms, processes, parameters, assumptions,...WHATSOEVER: It's a'' Jack-in-the-Box'' Universe!!! ONLY VIA: Bose-{Euler[(1732)] sum =product over-reals R-Riemann[Monats. Akad.,(1859)] sum =product over-complexs)-Bernoulli-Kummer}-Newcomb[Am. J. Math. 4(1), 39(1881) THE discovery of the QUANTUM!!!]-{Planck(1901)]-Einstein(1905)]-Sommerfeld}-Poincare[Calcul des Probabilités, 313 (1912)]-Weyl[Goett. Nach.(1914); Math. Ann. 77, 313(1916)]-(Bose(1924)-Einstein(1925)]-VS.

  4. Transforming business models through big data in the textile industry

    DEFF Research Database (Denmark)

    Aagaard, Annabeth

    as stressed by Zott et al. (2011), Weill et al. (2011) and David J. Teece (2010: 174), who states that: “the concept of a business model lacks theoretical grounding in economics or in business studies”. With the acceleration of digitization and use of big data analytics quality data are accessible......, such as textile, and have led to disruption of established business models (Westerman et al., 2014; Weill and Woerner, 2015). Yet, little is known of the managerial process and facilitation of the digital transformation of business models through big data (McAfee and Brynjolfsson, 2012; Markus and Loebbecke, 2013)....

  5. Study of Humorous Language in Sitcom TheBigBangTheoryunder Skopostheory%目的论视角下《生活大爆炸》中幽默语的翻译

    Institute of Scientific and Technical Information of China (English)

    方欣

    2013-01-01

    Humor is the carrier of language and culture. With the development of intercultural communication, there are more studies on humor, most of which are from the perspectives of literature, arts or psychology. Very few studies on humor are taken in view of translation. Some scholars even consider humor as untranslatable. The translation of humor enables people from differ⁃ent cultures to share joy with one another. This essay takes Skopostheory as theoretical basis, analyzing the humorous language in the popular American sitcom TheBigBangTheoryand evaluating different translation strategies adopted.%  幽默是一种语言和文化内涵的载体,随着跨文化交流的日益频繁,越来越多的人对幽默有所探索。目前对幽默的研究大都是从文学、艺术、心理学等角度,但是从翻译的侧面对幽默的研究并不多,有些学者甚至认为幽默是不可翻译的。幽默语的翻译可以使来自不同文化背景人们相互之间更好地分享幽默。该文以功能翻译目的论为理论依据,选取时下流行的美国情景喜剧《生活大爆炸》中的幽默语言为案例,分析译者在翻译幽默语时所采取的具体策略及其得失。

  6. An Analysis of Humorous Effects of Turn-taking---A Case Study of The Big Bang Theory%以《生活大爆炸》为例分析话轮转换的幽默效果

    Institute of Scientific and Technical Information of China (English)

    刘馨林

    2014-01-01

    In daily conversation , turn-taking is a very common phenomenon .Turn-taking is first proposed by the founders of conversational analysis ,Harvey Sacks , Emanuel Schegolff and Gail Jefferson .They summarize the turn-taking rules in personal communication so that the rules can help people to analyze different effects as a result of turn-taking mechanism , such as humorous effects of expressions .This paper attempts to expound what turn-taking is, what turn-taking strategies are , and analyze how to use turn-taking strategies to produce humorous conversations by taking the sitcom , The Big Bang Theory , as an example .%在日常会话中,话轮转换是一种普遍现象。话轮转换最初是由话语分析学派的开创者Harvey Sacks ,Emanuel Schegolff和Gail Jefferson提出的。他们总结了在交流中话轮转换的规则,从而帮助人们分析由话轮转换机制产生的不同表达效果,例如通过话轮转换产生幽默的会话效果。主要阐述话轮转换概念,话轮转换策略,并以《生活大爆炸》为例,揭示如何利用话轮转换策略表达出幽默的会话效果。

  7. 从语境角度分析《生活大爆炸》中的幽默言语%Analysis of the Humorous Discourse in The Big Bang Theory from the Perspective of Cognitive Environment

    Institute of Scientific and Technical Information of China (English)

    张黎

    2014-01-01

    该文以关联理论为基础,从认知语境的角度对《生活大爆炸》中幽默话语进行了分析,阐述了认知语境产生幽默所应具备的条件,以及影响个人认知语境的几个因素。以往的幽默研究着重强调交流双方在具有共同的认知语境之下产生的幽默,这篇文章指出交际双方在认知语境方面存在的差异很多时候是幽默制造的必需品;研究突破了传统的对语境的研究,从不同的角度阐述了认知语境与幽默之间存在着的的关系。%Based on Relevance Theory, This paper analyzed the humorous dialogues in American sitcom The Big Bang Theory from the perspective of cognitive environment to elaborate the necessary conditions of cognitive environment for humor genera-tion as well as the factors which influence people’s cognitive environment. Previous studies of humor always emphasize the hu-mor generated when two parties of communication have the same cognitive environment. This paper pointed out that the differ-ences of cognitive environment between both sides of communication are often the necessities for humor manufacturing;besides, the research broken through the traditional single general study of cognitive environment, and fully elaborated the varied and complicated relationship between cognitive environment and humor from a new perspective.

  8. Past Eras In Cyclic Cosmological Models

    CERN Document Server

    Frampton, Paul H

    2009-01-01

    In infinitely cyclic cosmology past eras are discussed using set theory and transfinite numbers. One consistent scenario, already in the literature, is where there is always a countably infinite number, $\\aleph_0$, of universes and no big bang. I describe here an alternative where the present number of universes is $\\aleph_0$ and in the infinite past there was only a finite number of universes. In this alternative model it is also possible that there was no big bang.

  9. Changing the personality of a face: Perceived Big Two and Big Five personality factors modeled in real photographs.

    Science.gov (United States)

    Walker, Mirella; Vetter, Thomas

    2016-04-01

    General, spontaneous evaluations of strangers based on their faces have been shown to reflect judgments of these persons' intention and ability to harm. These evaluations can be mapped onto a 2D space defined by the dimensions trustworthiness (intention) and dominance (ability). Here we go beyond general evaluations and focus on more specific personality judgments derived from the Big Two and Big Five personality concepts. In particular, we investigate whether Big Two/Big Five personality judgments can be mapped onto the 2D space defined by the dimensions trustworthiness and dominance. Results indicate that judgments of the Big Two personality dimensions almost perfectly map onto the 2D space. In contrast, at least 3 of the Big Five dimensions (i.e., neuroticism, extraversion, and conscientiousness) go beyond the 2D space, indicating that additional dimensions are necessary to describe more specific face-based personality judgments accurately. Building on this evidence, we model the Big Two/Big Five personality dimensions in real facial photographs. Results from 2 validation studies show that the Big Two/Big Five are perceived reliably across different samples of faces and participants. Moreover, results reveal that participants differentiate reliably between the different Big Two/Big Five dimensions. Importantly, this high level of agreement and differentiation in personality judgments from faces likely creates a subjective reality which may have serious consequences for those being perceived-notably, these consequences ensue because the subjective reality is socially shared, irrespective of the judgments' validity. The methodological approach introduced here might prove useful in various psychological disciplines. (PsycINFO Database Record

  10. Big Data for Infectious Disease Surveillance and Modeling

    DEFF Research Database (Denmark)

    Bansal, Shweta; Chowell, Gerardo; Simonsen, Lone

    2016-01-01

    for public health, one encompassing patient information gathered from high-volume electronic health records and participatory surveillance systems, as well as mining of digital traces such as social media, Internet searches, and cell-phone logs. We introduce nine independent contributions to this special......We devote a special issue of the Journal of Infectious Diseases to review the recent advances of big data in strengthening disease surveillance, monitoring medical adverse events, informing transmission models, and tracking patient sentiments and mobility. We consider a broad definition of big data...... issue and highlight several cross-cutting areas that require further research, including representativeness, biases, volatility, and validation, and the need for robust statistical and hypotheses-driven analyses. Overall, we are optimistic that the big-data revolution will vastly improve the granularity...

  11. 范畴层次视域下的美国情景剧《生活大爆炸》中的言语幽默%Interpretation of Verbal Humor in Sitcom the Big Bang Theory from the Perspective of Categorization Levels

    Institute of Scientific and Technical Information of China (English)

    雷丽岚; 周蓓

    2011-01-01

    《生活大爆炸》是最近热播的情景喜剧,讲述四个情商极低的科学家和一个美女邻居之间的故事。试图运用范畴层次理论来阐释其特有的言语幽默。%The big bang theory is a very popular sitcom telling what happened between four scientists with a low EQ and a neighbor beauty.The paper tries to interpret its special verbal humor from the perspective of categorization levels.

  12. Translating strategy of cultural defaults of subtitles ---Taking The Big Bang Theory for example%影视字幕中文化缺省的翻译策略——以《生活大爆炸》为例

    Institute of Scientific and Technical Information of China (English)

    章程

    2012-01-01

    Many cultural defauhs exist in audiovisuals. Subtitle translation, as a new kind of art translation, has its own characteristics. This paper, taking American audiovisual The Big Bang Theory for example, explores translation strategies of cultural defaults.%在影视作品中存在大量的文化缺省现象。字幕翻译作为一种新的文学翻译形式有着它自身的特点。以美剧《生活大爆炸》为例,探讨影视作品中文化缺省的翻译策略。

  13. GALAXY EVOLUTION. An over-massive black hole in a typical star-forming galaxy, 2 billion years after the Big Bang.

    Science.gov (United States)

    Trakhtenbrot, Benny; Urry, C Megan; Civano, Francesca; Rosario, David J; Elvis, Martin; Schawinski, Kevin; Suh, Hyewon; Bongiorno, Angela; Simmons, Brooke D

    2015-07-10

    Supermassive black holes (SMBHs) and their host galaxies are generally thought to coevolve, so that the SMBH achieves up to about 0.2 to 0.5% of the host galaxy mass in the present day. The radiation emitted from the growing SMBH is expected to affect star formation throughout the host galaxy. The relevance of this scenario at early cosmic epochs is not yet established. We present spectroscopic observations of a galaxy at redshift z = 3.328, which hosts an actively accreting, extremely massive BH, in its final stages of growth. The SMBH mass is roughly one-tenth the mass of the entire host galaxy, suggesting that it has grown much more efficiently than the host, contrary to models of synchronized coevolution. The host galaxy is forming stars at an intense rate, despite the presence of a SMBH-driven gas outflow.

  14. ALMA observations of the host galaxy of GRB 090423 at z = 8.23: deep limits on obscured star formation 630 million years after the big bang

    Energy Technology Data Exchange (ETDEWEB)

    Berger, E.; Zauderer, B. A.; Chary, R.-R.; Laskar, T.; Chornock, R.; Davies, J. E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Tanvir, N. R. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Stanway, E. R.; Levan, A. J. [Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Levesque, E. M. [CASA, University of Colorado UCB 389, Boulder, CO 80309 (United States)

    2014-12-01

    We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB 090423 at z = 8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3σ limits of F {sub ν}(222 GHz) ≲ 33 μJy and F {sub ν}(3.6 μm) ≲ 81 nJy. The FIR limit is about 20 times fainter than the luminosity of the local ULIRG Arp 220 and comparable to the local starburst M 82. Comparing this with model spectral energy distributions, we place a limit on the infrared (IR) luminosity of L {sub IR}(8-1000 μm) ≲ 3 × 10{sup 10} L {sub ☉}, corresponding to a limit on the obscured star formation rate of SFR{sub IR}≲5 M {sub ☉} yr{sup –1}. For comparison, the limit on the unobscured star formation rate from Hubble Space Telescope rest-frame ultraviolet (UV) observations is SFR{sub UV} ≲ 1 M {sub ☉} yr{sup –1}. We also place a limit on the host galaxy stellar mass of M {sub *} ≲ 5 × 10{sup 7} M {sub ☉} (for a stellar population age of 100 Myr and constant star formation rate). Finally, we compare our millimeter observations to those of field galaxies at z ≳ 4 (Lyman break galaxies, Lyα emitters, and submillimeter galaxies) and find that our limit on the FIR luminosity is the most constraining to date, although the field galaxies have much larger rest-frame UV/optical luminosities than the host of GRB 090423 by virtue of their selection techniques. We conclude that GRB host galaxies at z ≳ 4, especially those with measured interstellar medium metallicities from afterglow spectroscopy, are an attractive sample for future ALMA studies of high redshift obscured star formation.

  15. Statistical model selection with “Big Data”

    Directory of Open Access Journals (Sweden)

    Jurgen A. Doornik

    2015-12-01

    Full Text Available Big Data offer potential benefits for statistical modelling, but confront problems including an excess of false positives, mistaking correlations for causes, ignoring sampling biases and selecting by inappropriate methods. We consider the many important requirements when searching for a data-based relationship using Big Data, and the possible role of Autometrics in that context. Paramount considerations include embedding relationships in general initial models, possibly restricting the number of variables to be selected over by non-statistical criteria (the formulation problem, using good quality data on all variables, analyzed with tight significance levels by a powerful selection procedure, retaining available theory insights (the selection problem while testing for relationships being well specified and invariant to shifts in explanatory variables (the evaluation problem, using a viable approach that resolves the computational problem of immense numbers of possible models.

  16. Online Knowledge-Based Model for Big Data Topic Extraction.

    Science.gov (United States)

    Khan, Muhammad Taimoor; Durrani, Mehr; Khalid, Shehzad; Aziz, Furqan

    2016-01-01

    Lifelong machine learning (LML) models learn with experience maintaining a knowledge-base, without user intervention. Unlike traditional single-domain models they can easily scale up to explore big data. The existing LML models have high data dependency, consume more resources, and do not support streaming data. This paper proposes online LML model (OAMC) to support streaming data with reduced data dependency. With engineering the knowledge-base and introducing new knowledge features the learning pattern of the model is improved for data arriving in pieces. OAMC improves accuracy as topic coherence by 7% for streaming data while reducing the processing cost to half.

  17. Online Knowledge-Based Model for Big Data Topic Extraction

    Science.gov (United States)

    Khan, Muhammad Taimoor; Durrani, Mehr; Khalid, Shehzad; Aziz, Furqan

    2016-01-01

    Lifelong machine learning (LML) models learn with experience maintaining a knowledge-base, without user intervention. Unlike traditional single-domain models they can easily scale up to explore big data. The existing LML models have high data dependency, consume more resources, and do not support streaming data. This paper proposes online LML model (OAMC) to support streaming data with reduced data dependency. With engineering the knowledge-base and introducing new knowledge features the learning pattern of the model is improved for data arriving in pieces. OAMC improves accuracy as topic coherence by 7% for streaming data while reducing the processing cost to half. PMID:27195004

  18. Multidimensional Big Spatial Data Modeling Through A Case Study: Lte Rf Subsystem Power Consumption Modeling

    DEFF Research Database (Denmark)

    Antón Castro, Francesc/François; Musiige, Deogratius; Mioc, Darka

    2016-01-01

    This paper presents a case study for comparing different multidimensional mathematical modeling methodologies used in multidimensional spatial big data modeling and proposing a new technique. An analysis of multidimensional modeling approaches (neural networks, polynomial interpolation and homotopy...

  19. Personality correlates of pathological gambling derived from Big Three and Big Five personality models.

    Science.gov (United States)

    Miller, Joshua D; Mackillop, James; Fortune, Erica E; Maples, Jessica; Lance, Charles E; Keith Campbell, W; Goodie, Adam S

    2013-03-30

    Personality traits have proved to be consistent and important factors in a variety of externalizing behaviors including addiction, aggression, and antisocial behavior. Given the comorbidity of these behaviors with pathological gambling (PG), it is important to test the degree to which PG shares these trait correlates. In a large community sample of regular gamblers (N=354; 111 with diagnoses of pathological gambling), the relations between measures of two major models of personality - Big Three and Big Five - were examined in relation to PG symptoms derived from a semi-structured diagnostic interview. Across measures, traits related to the experience of strong negative emotions were the most consistent correlates of PG, regardless of whether they were analyzed using bivariate or multivariate analyses. In several instances, however, the relations between personality and PG were moderated by demographic variable such as gender, race, and age. It will be important for future empirical work of this nature to pay closer attention to potentially important moderators of these relations.

  20. Analysis of The Big Bang Theory's Subtitle Translationfrom the Perspective of Eco-translatology%生态翻译学视角下情景喜剧字幕翻译的研究--以《生活大爆炸》为例

    Institute of Scientific and Technical Information of China (English)

    杨喆

    2014-01-01

    生态翻译学是近年来兴起的一个根植于中国的翻译理论,它是一个完整的理论系统,解决了“何为译”、“如何译”、“为何译”等一系列问题。而《生活大爆炸》作为一部吸引了无数中国人眼球的情景喜剧,其成功的字幕翻译无疑为其在中国的传播起到了举足轻重的作用。本文试从生态翻译学“如何译”的角度,即“三维”转换角度来分析《生活大爆炸》中的字幕翻译。%Eco-translatology is a newly developed translation theory that rooted in China. It's a comprehensive theory system which deals with many important translation questions such as what is translation, how to translate, why do people translate and so on. The Big Bang Theory is a popular sitcom among Chinese. And its success is closely related to its subtitle translation. This paper will mainly analyze the subtitle translation of The Big Bang Theory with three-dimensional transformations.

  1. Re-creating the big bang

    CERN Multimedia

    Mung, Adrienne

    2007-01-01

    "Deep beneath the Swiss-French border near Geneva, thousands of physicists rushed to build the world's largest and most expensive science experiment that they hope will bring them one step closer toward unlocking some of the universe's oldest secrets." (1,5 page)

  2. Pooling resources to decypher the Big Bang

    CERN Multimedia

    Harvey, Fiona

    2003-01-01

    " Work has started on a "virtual supercomputer" that will be the world's second most powerful data processor. The virtual computer will take the form of a "grid", a technology that links many smaller computers to make one huge computing resource" (1/2 page.

  3. Pooling resources to decypher the Big Bang

    CERN Multimedia

    Harvey, F

    2003-01-01

    "Work has started on a "virtual supercomputer" that will be the world's second most powerful data processor. The virtual computer will take the form of a "grid", a technology that links many smaller computers to make one huge computing resource" (1/2 page)

  4. From pop to the Big Bang

    CERN Multimedia

    Sutherland, Paul

    2007-01-01

    "An amazing new movie takes us to the brink of the end of the world. Sunshine whisks us to a moment 50 years in the future when the sun is about to die, attacked by rogue particles made at the start of time." (2 pages)

  5. Inside the big-bang machine

    CERN Multimedia

    Boyle, Alan

    2007-01-01

    "The future of particle physics is being built below ground, in a setting that's more appropriate for construction hardhats than lab coats. To get to the caverns where the world's most powerful particle collider is taking shape, you have to take an industrial-issue elevator down just one floor. But that floor is a doozy: it's about 100 meters below ground, roughly as deep as a 30-story building is tall." (2 pages)

  6. On the Cold Big Bang Cosmology

    Directory of Open Access Journals (Sweden)

    Assis A. V. D. B.

    2011-04-01

    Full Text Available We solve the general relativity (GR field equations under the cosmological scope via one extra postulate. The plausibility of the postulate resides within the Heisenberg in- determinacy principle, being heuristically analysed throughout the appendix. Under this approach, a negative energy density may provide the positive energy content of the universe via fluctuation, since the question of conservation of energy in cosmol- ogy is weakened, supported by the known lack of scope of the Noether’s theorem in cosmology. The initial condition of the primordial universe turns out to have a natural cuto such that the temperature of the cosmological substratum converges to the ab- solute zero, instead of the established divergence at the very beginning. The adopted postulate provides an explanation for the cosmological dark energy open question. The solution agrees with cosmological observations, including a 2.7K CMBT prediction.

  7. Museum makes room for the Big Bang

    CERN Multimedia

    Pinnell, Heather

    2007-01-01

    "Heather Pinnell discovers that a small exhibition about the Large Hadron Collider scored very highly for its impact." The museum has plans to add a spark chamber into the gallery to show that the experiments done at CERM are safe. (2/3 page)

  8. Scientists hope collider makes a big bang

    CERN Multimedia

    Nickerson, Colin

    2007-01-01

    "In a 17-ile circular tunnel curving beneath the Swiss-French border, scientists are poised to recreate the universe's first trillionth of a second. The aim of the audacious undertaking is to solve one of the most perturbing puzzles of physics: How did matter attain mass and form the cosmos? (2 pages)

  9. Dal Big Bang infiniti universi nascosti

    CERN Multimedia

    Valsecchi, Maria Cristina

    2005-01-01

    The intensity of the gravitational force, the speed with which the universe expands, the electric power of the electron, the speed of the light. That's some fundamental constants, some values which determine the characteristics of the universe surrounding us (½ page)

  10. Pa spaning efter Big Bang i underjorden

    CERN Multimedia

    Granström, Helena

    2008-01-01

    The LHC will start this summer; an accelerator placed in a 27km long annel. The machine will collide particles in order to test the theory of dark matter, dark energy and supersymmetry. We will get to know much more, but maybe understand even less. (4 pages)

  11. Still waiting for that Big Bang...

    CERN Multimedia

    2009-01-01

    "It has been called the greatest and most ambitious science experiment ever built by man. When operating at full power, the Large Hadron Collider - Europe's 3.2 billion (pounds) particle accelerator - will hurl beams of protons around its rings at a fraction of a per cent less than the speed of light" (2 pages)

  12. Testing out the Big bang theory

    CERN Multimedia

    Rumford, Alex

    2007-01-01

    "Bristol University academics are among some of the finest minds in the world toiling in a mind-blowingly massive laboratory to find answers to some of the biggest questions that can be asked - about life, the universe and everything. Lucy Parkinson travelled to Switzerland to find out what they are doing there." (2 pages)

  13. Seeking nature of God in Big Bang

    CERN Multimedia

    2008-01-01

    ""The most exciting thing of all," says Professor Peter Watkins with a smile, "is we have absolutely no idea what will happen until we switch it on." When you realise that the University of Birmingham academic is referring to the world's largest particle physics experiment, it is a little disconcerting. After 13 years of planning and construction, the Large Hadron Collider (LHC), is due to begin its work in the spring of 2008."

  14. On the Cold Big Bang Cosmology

    Directory of Open Access Journals (Sweden)

    Assis A. V. D. B.

    2011-04-01

    Full Text Available We solve the general relativity (GR field equations under the cosmological scope via one extra postulate. The plausibility of the postulate resides within the Heisenberg indeterminacy principle, being heuristically analysed throughout the appendix. Under this approach, a negative energy density may provide the positive energy content of the universe via fluctuation, since the question of conservation of energy in cosmology is weakened, supported by the known lack of scope of the Noether's theorem in cosmology. The initial condition of the primordial universe turns out to have a natural cutoff such that the temperature of the cosmological substratum converges to the absolute zero, instead of the established divergence at the very beginning. The adopted postulate provides an explanation for the cosmological dark energy open question. The solution agrees with cosmological observations, including a 2.7K CMBT prediction.

  15. UH team expands big-bang theory

    CERN Multimedia

    Creamer, B

    2002-01-01

    After six months of research at a new underground neutrino detector near the central Japan city of Toyama, an international research team announced yesterday that neutrinos have mass and are capable of morphing from one type to another (1 page).

  16. A la poursuite du Big Bang

    CERN Multimedia

    Bois, Jérome

    2008-01-01

    Hundred meters under the Pays de Gex, at the end of July, billions of particles are going to be throwed at 99,99% of the speed of the light to recreate the conditions having existed at the origin of the Universe. (1 page)

  17. The Meta-Analytic Big Bang

    Science.gov (United States)

    Shadish, William R.; Lecy, Jesse D.

    2015-01-01

    This article looks at the impact of meta-analysis and then explores why meta-analysis was developed at the time and by the scholars it did in the social sciences in the 1970s. For the first problem, impact, it examines the impact of meta-analysis using citation network analysis. The impact is seen in the sciences, arts and humanities, and on such…

  18. Oceanic turbulence - Big bangs or continuous creation?

    Science.gov (United States)

    Caldwell, D. R.

    1983-01-01

    A hypothesis concerning the turbulence characteristics of 'microstructure' patches in the ocean is proposed in which a turbulence field is driven at the same time and scale at which it is observed. The driving energy is converted into turbulence kinetic energy in such a way that the observed overturning thickness scale is linearly related to the length scale. This hypothesis is contrasted with that of Gibson (1982), in which the 'patches' are produced by rare, powerful turbulence generators that have 'fossilized' prior to their observation. Careful attention is given to the sampling process and its assumptions.

  19. Big Bang and context-driven collapse.

    Science.gov (United States)

    Robertson-Tessi, Mark; Anderson, Alexander R A

    2015-03-01

    Heterogeneity is the single most important factor driving cancer progression and treatment failure, yet little is understood about how and when this heterogeneity arises. A new study shows that colorectal cancers acquire their dominant mutations early in development and that subsequent mutations, even if they confer greater fitness, are unlikely to sweep through the tumor.

  20. Tracking Back to the Big Bang.

    Science.gov (United States)

    Peat, David

    1983-01-01

    Traces some astronomical history and considers how astronomers have arrived at their current knowledge of distance, size, and time as it applies to objects in the night sky. The information is provided as background to a discussion of the Hubble constant and its relationship to the age of the universe. (JN)

  1. Motivating Reluctant Learners with a Big Bang

    Science.gov (United States)

    Lochner, James C.; Cvetic, Geraldine A.; Hall, Jonathan B.

    2007-01-01

    We present results of a collaboration between a media specialist, a science teacher, and an astronomer to bring a modern astronomy topic to at-risk, emotionally disabled students who have experienced little success. These normally unengaged students became highly motivated because they were given an authentic task of presenting research on an intriguing science topic, and because they witnessed a collaboration brought together on their behalf This experience demonstrates that sophisticated astronomy topics can be used to motivate at-risk students.

  2. GRAMMAR RULE BASED INFORMATION RETRIEVAL MODEL FOR BIG DATA

    Directory of Open Access Journals (Sweden)

    T. Nadana Ravishankar

    2015-07-01

    Full Text Available Though Information Retrieval (IR in big data has been an active field of research for past few years; the popularity of the native languages presents a unique challenge in big data information retrieval systems. There is a need to retrieve information which is present in English and display it in the native language for users. This aim of cross language information retrieval is complicated by unique features of the native languages such as: morphology, compound word formations, word spelling variations, ambiguity, word synonym, other language influence and etc. To overcome some of these issues, the native language is modeled using a grammar rule based approach in this work. The advantage of this approach is that the native language is modeled and its unique features are encoded using a set of inference rules. This rule base coupled with the customized ontological system shows considerable potential and is found to show better precision and recall.

  3. Modeling genomic regulatory networks with big data.

    Science.gov (United States)

    Bolouri, Hamid

    2014-05-01

    High-throughput sequencing, large-scale data generation projects, and web-based cloud computing are changing how computational biology is performed, who performs it, and what biological insights it can deliver. I review here the latest developments in available data, methods, and software, focusing on the modeling and analysis of the gene regulatory interactions in cells. Three key findings are: (i) although sophisticated computational resources are increasingly available to bench biologists, tailored ongoing education is necessary to avoid the erroneous use of these resources. (ii) Current models of the regulation of gene expression are far too simplistic and need updating. (iii) Integrative computational analysis of large-scale datasets is becoming a fundamental component of molecular biology. I discuss current and near-term opportunities and challenges related to these three points.

  4. SETI as a part of Big History

    Science.gov (United States)

    Maccone, Claudio

    2014-08-01

    Big History is an emerging academic discipline which examines history scientifically from the Big Bang to the present. It uses a multidisciplinary approach based on combining numerous disciplines from science and the humanities, and explores human existence in the context of this bigger picture. It is taught at some universities. In a series of recent papers ([11] through [15] and [17] through [18]) and in a book [16], we developed a new mathematical model embracing Darwinian Evolution (RNA to Humans, see, in particular, [17] and Human History (Aztecs to USA, see [16]) and then we extrapolated even that into the future up to ten million years (see 18), the minimum time requested for a civilization to expand to the whole Milky Way (Fermi paradox). In this paper, we further extend that model in the past so as to let it start at the Big Bang (13.8 billion years ago) thus merging Big History, Evolution on Earth and SETI (the modern Search for ExtraTerrestrial Intelligence) into a single body of knowledge of a statistical type. Our idea is that the Geometric Brownian Motion (GBM), so far used as the key stochastic process of financial mathematics (Black-Sholes models and related 1997 Nobel Prize in Economics!) may be successfully applied to the whole of Big History. In particular, in this paper we derive book about GBMs will be written by the author. Mass Extinctions of the geological past also are one more topic that may be cast in the language of a decreasing GBM over a short time lapse, since Mass Extinctions are sudden all-lows in the number of living species. In this paper, we give formulae for the decreasing GBMs of Mass Extinctions, like the K-Pg one of 64 million years ago. Finally, we note that the Big History Equation is just the extension of the Drake Equation to 13.8 billion years of cosmic evolution. So, the relevant GBM starting at the Big Bang epoch (13.8 billion years ago) and growing up to nowadays in a stochastically increasing fashion becomes the GBM

  5. Special Issue: Big data and predictive computational modeling

    Science.gov (United States)

    Koutsourelakis, P. S.; Zabaras, N.; Girolami, M.

    2016-09-01

    The motivation for this special issue stems from the symposium on "Big Data and Predictive Computational Modeling" that took place at the Institute for Advanced Study, Technical University of Munich, during May 18-21, 2015. With a mindset firmly grounded in computational discovery, but a polychromatic set of viewpoints, several leading scientists, from physics and chemistry, biology, engineering, applied mathematics, scientific computing, neuroscience, statistics and machine learning, engaged in discussions and exchanged ideas for four days. This special issue contains a subset of the presentations. Video and slides of all the presentations are available on the TUM-IAS website http://www.tum-ias.de/bigdata2015/.

  6. String Propagation through a Big Crunch/Big Bang Transition

    CERN Document Server

    Tolley, A J

    2005-01-01

    We consider the propagation of classical and quantum strings on cosmological space-times which interpolate from a collapsing phase to an expanding phase. We begin by considering the classical propagation of strings on space-times with isotropic and anisotropic cosmological singularities. We find that cosmological singularities fall into two classes, in the first class the string evolution is well behaved all the way up to the singularity, whilst in the second class it becomes ill-defined. Then assuming the singularities are regulated by string scale corrections, we consider the implications of the propagation through a `bounce'. It is known that as we evolve through a bounce, quantum strings will become excited giving rise to `particle transmutation'. We reconsider this effect, giving qualitative arguments for the amount of excitation for each class. We find that strings whose physical wavelength at the bounce is less that $\\sqrt{\\alpha'}$ inevitably emerge in highly excited states, and that in this regime th...

  7. Big Bang Day : The Great Big Particle Adventure - 1. Atom

    CERN Document Server

    Steven Weinberg; Terry White; John Ellis; Jim Virdee

    2008-01-01

    In this series, comedian and physicist Ben Miller asks the CERN scientists what they hope to find. The notion of atoms dates back to Greek philosophers who sought a natural mechanical explanation of the Universe, as opposed to a divine one. The existence what we call chemical atoms, the constituents of all we see around us, wasn't proved until a hundred years ago, but almost simultaneously it was realised these weren't the indivisible constituents the Greeks envisaged. Much of the story of physics since then has been the ever-deeper probing of matter until, at the end of the 20th century, a complete list of fundamental ingredients had been identified, apart from one, the much discussed Higgs particle. In this programme, Ben finds out why this last particle is so pivotal, not just to atomic theory, but to our very existence - and how hopeful the scientists are of proving its existence.

  8. Bianchi Type-I Massive String Magnetized Barotropic Perfect Fluid Cosmological Model in the Bimetric Theory of Gravitation

    Institute of Scientific and Technical Information of China (English)

    N. P. Gaikwad; M. S. Borkar; S. S. Charjan

    2011-01-01

    @@ We investigate the Bianchi type-I massive string magnetized barotropic perfect fluid cosmological model in Rosen's bimetric theory of gravitation with and without a magnetic field by applying the techniques used by Latelier(1979,1980) and Stachel(1983).To obtain a deterministic model of the universe, it is assumed that the universe is filled with barotropic perfect fluid distribution.The physical and geometrical significance of the model are discussed.By comparing our model with the model of Bali et al.(2007), it is realized that there are no big-bang and big-crunch singularities in our model and T=0 is not the time of the big bang, whereas the model of Bali et al.starts with a big bang at T=0.Further, our model is in agreement with Bali et al.(2007) as time increases in the presence, as well as in the absence, of a magnetic field.

  9. On Comic Effect of The Big Bang Theory from the Perspective of Violating Politeness Maxim%从违反礼貌原则的角度浅析《生活大爆炸》对白的幽默效果

    Institute of Scientific and Technical Information of China (English)

    章丹

    2014-01-01

    Humor is a key feature of the sitcoms. The Big Bang Theory is recently hitting ratings high in America. The sitcom is well written and features an endearing cast who provides viewers with lots of humorous moments. This essay focuses on pragmatic analysis of the dialogues in Season 6 which have comic effect emerged by violating the six maxims of politeness principles.%幽默是情景喜剧的精髓所在。《生活大爆炸》是近几年热播的一美剧。剧情幽默风趣,经常让观众捧腹大笑。本文以本片第六季为蓝本分别从违反礼貌原则的六个准则角度分析其对白的幽默效果。

  10. ExpIanation of the Humorous Utterances Based on the ReIevance Theory---Take The Big Bang Theory for ExampIe%从关联理论角度解释话语幽默--以美剧《生活大爆炸》为例

    Institute of Scientific and Technical Information of China (English)

    史岩

    2015-01-01

    Selecting large quantities of humorous utterances from the American TV series The Big Bang Theory,this paper aims to explore how the humor is produced and understood based on the Relevance Theory. The fact proved that the Relevance Theory can ex-plain the humorous utterances forcefully and it paves a new way for the research on humorous utterances.%选取《生活大爆炸》中大量幽默言语,从关联理论出发,探究幽默是如何产生的,又是怎样被理解的。事实证明关联理论对幽默言语具有很强的解释力,为幽默话语研究开拓了新领域。

  11. Reviews Book: Nucleus Book: The Wonderful World of Relativity Book: Head Shot Book: Cosmos Close-Up Places to Visit: Physics DemoLab Book: Quarks, Leptons and the Big Bang EBook: Shooting Stars Equipment: Victor 70C USB Digital Multimeter Web Watch

    Science.gov (United States)

    2012-09-01

    WE RECOMMEND Nucleus: A Trip into the Heart of Matter A coffee-table book for everyone to dip into and learn from The Wonderful World of Relativity A charming, stand-out introduction to relativity The Physics DemoLab, National University of Singapore A treasure trove of physics for hands-on science experiences Quarks, Leptons and the Big Bang Perfect to polish up on particle physics for older students Victor 70C USB Digital Multimeter Equipment impresses for usability and value WORTH A LOOK Cosmos Close-Up Weighty tour of the galaxy that would make a good display Shooting Stars Encourage students to try astrophotography with this ebook HANDLE WITH CARE Head Shot: The Science Behind the JKF Assassination Exploration of the science behind the crime fails to impress WEB WATCH App-lied science for education: a selection of free Android apps are reviewed and iPhone app options are listed

  12. 从文化翻译论看美剧《生活大爆炸》的字幕翻译策略%On the Subtitle Translation of the US TV series The Big Bang Theory, with Reference to the Cultural Translation Theory

    Institute of Scientific and Technical Information of China (English)

    齐佳宁; 田翠芸; 刘颖

    2014-01-01

    随着国际化的逐步加深,影视作品作为一种文化传播媒介在人们的日常生活中扮演着越来越重要的角色。而字幕翻译作为国际交流的工具,在国际影视作品传播过程中发挥着关键的作用。运用文化翻译论分析了美剧《生活大爆炸》的字幕翻译,并结合其制造的视听效果,初步总结了影视字幕的翻译方法和翻译策略,为影视字幕翻译提供一些借鉴。%with the general deepening of the current trend towards internationalization , films and TV programs have become increasingly more important in cultural communication .Subtitle translation , which is an important tool of international communication , is quite crucial in the world-wide spread of films and TV programs .Referring to the Cultural Translation Theory , the US TV series The Big Bang Theory is analyzed in this thesis .With a comprehen-sive consideration of the visual and sound effects projected by the Big Bang Theory program , some subtitle transla-tion methods and strategies have been summarized , which, it is hoped, will provide some guidance for effective subtitle translation .

  13. 科学与影视娱乐交融的科普模式——以美国电视剧《生活大爆炸》为案例%Science and Entertainment: A Case Study on the American TV Series The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    王一鸣

    2012-01-01

    随着当代科学与社会及公众的联系更加紧密,借助于资讯与传媒的发达,产生了科学与影视娱乐交融的科普模式。美国电视剧《生活大爆炸》即是一部成功实践这种模式的生活情景喜剧,在娱乐中传播与普及科学知识,获得较大社会反响。分析了《生活大爆炸》的成功的运行机制和特点,并与中国现状进行了对比,同时在此基础上对科学传播与影视娱乐结合的科普方式进行了思考。%With the connection between contemporary science, society and people, and also by the progress of information and communication, the new method of science popularization through the integration of science and entertainment was generated. The American TV series The Big Bang Theory was one of that and obtained great social responding by communicating and popularizing the science through entertainment. The operating mechanism and features of The Big Bang Theory are analyzed. The current status of China is also discussed. Furthermore, the method of science popularization through the integration of science and entertainment is pondered.

  14. A genetic algorithm-based job scheduling model for big data analytics.

    Science.gov (United States)

    Lu, Qinghua; Li, Shanshan; Zhang, Weishan; Zhang, Lei

    Big data analytics (BDA) applications are a new category of software applications that process large amounts of data using scalable parallel processing infrastructure to obtain hidden value. Hadoop is the most mature open-source big data analytics framework, which implements the MapReduce programming model to process big data with MapReduce jobs. Big data analytics jobs are often continuous and not mutually separated. The existing work mainly focuses on executing jobs in sequence, which are often inefficient and consume high energy. In this paper, we propose a genetic algorithm-based job scheduling model for big data analytics applications to improve the efficiency of big data analytics. To implement the job scheduling model, we leverage an estimation module to predict the performance of clusters when executing analytics jobs. We have evaluated the proposed job scheduling model in terms of feasibility and accuracy.

  15. Building Simulation Modelers are we big-data ready?

    Energy Technology Data Exchange (ETDEWEB)

    Sanyal, Jibonananda [ORNL; New, Joshua Ryan [ORNL

    2014-01-01

    Recent advances in computing and sensor technologies have pushed the amount of data we collect or generate to limits previously unheard of. Sub-minute resolution data from dozens of channels is becoming increasingly common and is expected to increase with the prevalence of non-intrusive load monitoring. Experts are running larger building simulation experiments and are faced with an increasingly complex data set to analyze and derive meaningful insight. This paper focuses on the data management challenges that building modeling experts may face in data collected from a large array of sensors, or generated from running a large number of building energy/performance simulations. The paper highlights the technical difficulties that were encountered and overcome in order to run 3.5 million EnergyPlus simulations on supercomputers and generating over 200 TBs of simulation output. This extreme case involved development of technologies and insights that will be beneficial to modelers in the immediate future. The paper discusses different database technologies (including relational databases, columnar storage, and schema-less Hadoop) in order to contrast the advantages and disadvantages of employing each for storage of EnergyPlus output. Scalability, analysis requirements, and the adaptability of these database technologies are discussed. Additionally, unique attributes of EnergyPlus output are highlighted which make data-entry non-trivial for multiple simulations. Practical experience regarding cost-effective strategies for big-data storage is provided. The paper also discusses network performance issues when transferring large amounts of data across a network to different computing devices. Practical issues involving lag, bandwidth, and methods for synchronizing or transferring logical portions of the data are presented. A cornerstone of big-data is its use for analytics; data is useless unless information can be meaningfully derived from it. In addition to technical

  16. More than the Big Five: egoism and the HEXACO model of personality

    NARCIS (Netherlands)

    de Vries, R.E.; de Vries, A.; de Hoogh, A.; Feij, J.

    2009-01-01

    Egoism is a personality trait that is associated with self-enriching and self-centred behaviours. Research has suggested that egoism lies beyond the Big Five personality factors. Recently, the HEXACO model of personality has been proposed as an alternative to the Big Five model. In three studies, th

  17. Unleashing spatially distributed ecohydrology modeling using Big Data tools

    Science.gov (United States)

    Miles, B.; Idaszak, R.

    2015-12-01

    Physically based spatially distributed ecohydrology models are useful for answering science and management questions related to the hydrology and biogeochemistry of prairie, savanna, forested, as well as urbanized ecosystems. However, these models can produce hundreds of gigabytes of spatial output for a single model run over decadal time scales when run at regional spatial scales and moderate spatial resolutions (~100-km2+ at 30-m spatial resolution) or when run for small watersheds at high spatial resolutions (~1-km2 at 3-m spatial resolution). Numerical data formats such as HDF5 can store arbitrarily large datasets. However even in HPC environments, there are practical limits on the size of single files that can be stored and reliably backed up. Even when such large datasets can be stored, querying and analyzing these data can suffer from poor performance due to memory limitations and I/O bottlenecks, for example on single workstations where memory and bandwidth are limited, or in HPC environments where data are stored separately from computational nodes. The difficulty of storing and analyzing spatial data from ecohydrology models limits our ability to harness these powerful tools. Big Data tools such as distributed databases have the potential to surmount the data storage and analysis challenges inherent to large spatial datasets. Distributed databases solve these problems by storing data close to computational nodes while enabling horizontal scalability and fault tolerance. Here we present the architecture of and preliminary results from PatchDB, a distributed datastore for managing spatial output from the Regional Hydro-Ecological Simulation System (RHESSys). The initial version of PatchDB uses message queueing to asynchronously write RHESSys model output to an Apache Cassandra cluster. Once stored in the cluster, these data can be efficiently queried to quickly produce both spatial visualizations for a particular variable (e.g. maps and animations), as well

  18. Ontology-Based Big Dimension Modeling in Data Warehouse Schema Design

    DEFF Research Database (Denmark)

    Xiufeng, Liu; Iftikhar, Nadeem

    2013-01-01

    can automatically generate the data warehouse schema from the ontology of describing the terms and business semantics for the big dimension. In case of any change in the requirements, we only need to modify the ontology, and re-generate the schema using the tool. This paper also evaluates the proposed......During data warehouse schema design, designers often encounter how to model big dimensions that typically contain a large number of attributes and records. To investigate effective approaches for modeling big dimensions is necessary in order to achieve better query performance, with respect...... to response time. In most cases, the big dimension modeling process is complicated since it usually requires accurate description of business semantics, multiple design revisions and comprehensive testing. In this paper, we present the design methods for modeling big dimensions, which include horizontal...

  19. Transforming Healthcare Delivery: Integrating Dynamic Simulation Modelling and Big Data in Health Economics and Outcomes Research.

    Science.gov (United States)

    Marshall, Deborah A; Burgos-Liz, Lina; Pasupathy, Kalyan S; Padula, William V; IJzerman, Maarten J; Wong, Peter K; Higashi, Mitchell K; Engbers, Jordan; Wiebe, Samuel; Crown, William; Osgood, Nathaniel D

    2016-02-01

    In the era of the Information Age and personalized medicine, healthcare delivery systems need to be efficient and patient-centred. The health system must be responsive to individual patient choices and preferences about their care, while considering the system consequences. While dynamic simulation modelling (DSM) and big data share characteristics, they present distinct and complementary value in healthcare. Big data and DSM are synergistic-big data offer support to enhance the application of dynamic models, but DSM also can greatly enhance the value conferred by big data. Big data can inform patient-centred care with its high velocity, volume, and variety (the three Vs) over traditional data analytics; however, big data are not sufficient to extract meaningful insights to inform approaches to improve healthcare delivery. DSM can serve as a natural bridge between the wealth of evidence offered by big data and informed decision making as a means of faster, deeper, more consistent learning from that evidence. We discuss the synergies between big data and DSM, practical considerations and challenges, and how integrating big data and DSM can be useful to decision makers to address complex, systemic health economics and outcomes questions and to transform healthcare delivery.

  20. Statistical properties of first-order bang-bang Pll with nonzero loop delay

    OpenAIRE

    Chun, Byungjin; Kennedy, Michael Peter

    2008-01-01

    A method to solve the stationary state probability is presented for the first-order bang-bang phase-locked loop (BBPLL) with nonzero loop delay. This is based on a delayed Markov chain model and a state How diagram for tracing the state history due to the loop delay. As a result, an eigenequation is obtained, and its closed form solutions are derived for some cases. After obtaining the state probability, statistical characteristics such as mean gain of the binary phase detector and timing err...

  1. Information Literacy for Health Professionals: Teaching Essential Information Skills with the Big6 Information Literacy Model

    Science.gov (United States)

    Santana Arroyo, Sonia

    2013-01-01

    Health professionals frequently do not possess the necessary information-seeking abilities to conduct an effective search in databases and Internet sources. Reference librarians may teach health professionals these information and technology skills through the Big6 information literacy model (Big6). This article aims to address this issue. It also…

  2. The Relationship between the Big-Five Model of Personality and Self-Regulated Learning Strategies

    Science.gov (United States)

    Bidjerano, Temi; Dai, David Yun

    2007-01-01

    The study examined the relationship between the big-five model of personality and the use of self-regulated learning strategies. Measures of self-regulated learning strategies and big-five personality traits were administered to a sample of undergraduate students. Results from canonical correlation analysis indicated an overlap between the…

  3. Comment on "a simple inflationary quintessential model"

    CERN Document Server

    Fernandez-Jambrina, L

    2016-01-01

    In [1] a new cosmological model is proposed with no big bang singularity in the past. This model starts with an inflationary era, follows with a stiff matter dominated period and evolves to accelerated expansion in an asymptotically de Sitter regime. We argue that the initial singularity is in fact no big bang but a directional singularity which cannot be reached by comoving observers but by observers with nonzero linear momentum. Hence, the time lapse from the initial singularity can be as long as desired depending on the linear momentum of the observer. This conclusion applies to similar inflationary models. This sort of cosmological singularities have been postulated also in other scenarios.

  4. Crowdsourcing Big Trace Data Filtering: a Partition-And Model

    Science.gov (United States)

    Yang, X.; Tang, L.

    2016-06-01

    GPS traces collected via crowdsourcing way are low-cost and informative and being as a kind of new big data source for urban geographic information extraction. However, the precision of crowdsourcing traces in urban area is very low because of low-end GPS data devices and urban canyons with tall buildings, thus making it difficult to mine high-precision geographic information such as lane-level road information. In this paper, we propose an efficient partition-and-filter model to filter trajectories, which includes trajectory partitioning and trajectory filtering. For the partition part, the partition with position and angle constrain algorithm is used to partition a trajectory into a set of sub-trajectories based on distance and angle constrains. Then, the trajectory filtering with expected accuracy method is used to filter the sub-trajectories according to the similarity between GPS tracking points and GPS baselines constructed by random sample consensus algorithm. Experimental results demonstrate that the proposed partition-and-filtering model can effectively filter the high quality GPS data from various crowdsourcing trace data sets with the expected accuracy.

  5. The Study of Humor Utterance Translation in The Big Bang Theory from the Perspective of Relevance Theory%关联理论视角下美国情景喜剧《生活大爆炸》中幽默言语的翻译

    Institute of Scientific and Technical Information of China (English)

    俞娜莎

    2014-01-01

    《生活大爆炸》这一情景喜剧目前在美国深得人心。幽默诙谐的语言造就了该剧的成功。该文详细探讨了关联理论视角下情景喜剧《生活大爆炸》中的幽默言语翻译。该文首先论述了在关联理论视角下其幽默言语的产生机制;其次探究关联理论对幽默言语翻译的适用性;最后提出了关联理论视角下的可行的影视幽默言语翻译策略:格特的直接翻译策略和间接翻译策略,并详细例证了直接翻译的直译法、注释法和间接翻译的补充法、替代法和省译法等具体的翻译方法。%s:The Big Bang Theory has been a popular American sitcom. Humorous utterance greatly contributes to its success. This paper tries to discuss the humorous utterance translation from the perspective of Relevance Theory in detail. The paper firstly in⁃troduces the generative mechanism of humorous utterance from the perspective of Relevance Theory;then it discusses the appli⁃cability of Relevance Theory on humor translation;at last, it points out some subtitling translation strategies in The Big Bang The⁃ory from the perspective of Relevance Theory, namely, Gutt’s direct translation and indirect translation, and illustrates the specif⁃ic translation methods, that is, literal translation and annotation that belong to direct translation as well as supplement, replace⁃ment and omission that belong to indirect translation.

  6. The big seven model of personality and its relevance to personality pathology.

    Science.gov (United States)

    Simms, Leonard J

    2007-02-01

    Proponents of the Big Seven model of personality have suggested that Positive Valence (PV) and Negative Valence (NV) are independent of the Big Five personality dimensions and may be particularly relevant to personality disorder. These hypotheses were tested with 403 undergraduates who completed a Big Seven measure and markers of the Big Five and personality pathology. Results revealed that PV and NV incrementally predicted personality pathology dimensions beyond those predicted by multiple markers of the Big Five. However, factor analyses suggested that PV and NV might be best understood as specific, maladaptive aspects of positive emotionality and low agreeableness, respectively, as opposed to independent factors of personality. Implications for the description of normal and abnormal personality are discussed.

  7. 情景喜剧会话修正特征研究--基于《生活大爆炸》中的会话分析%Sitcom Session Correction Characteristic Research---Based on the Conversation Analysis of"The Big Bang Theory"

    Institute of Scientific and Technical Information of China (English)

    岳淑英; 党小玲

    2016-01-01

    There must be some spelling mistakes in the session,the pronunciation errors or misunderstanding and that can make the conversation go smoothly.The most effective way is to the session correction.Taking the 8th session in the sitcom of"The Big Bang Theory"as the corpus,based on the theory of Schegloff etc.,this paper make analysis on the characteristic of the session correction.%会话中必然存在一些拼写错误、发音错误或理解错误,而能够让会话顺利进行的最有效的方式即为会话修正。以情景喜剧《生活大爆炸》第八季中的会话为语料,基于Schegloff等人的理论,分析其中的会话修正特征。

  8. 从关联理论阐释话语标记语you know的语用功能--以美剧《生活大爆炸》为例%A Study on Pragmatic Functions of Discourse Marker You Know in The Big Bang Theory from the Perspective of Relevance Theory

    Institute of Scientific and Technical Information of China (English)

    李恒

    2016-01-01

    话语标记语,作为一种被广泛使用的语言现象,在过去40年来得到了国内外学者的关注。语言学家们大多就其定义及功能对其进行研究。本文以《生活大爆炸》第三季对白为语料,从关联理论对其中出现的话语标记语 you know的五种语用功能进行分析,帮助交际者更好地理解和生成话语,继而获得交际成功。%Discourse marker,as a widely used linguistic phenomenon,has gained the attention of scholars from home and abroad in the past 40 years.Linguists have been mostly focusing on its definition and functions.This paper tries to analyze the five pragmatic functions of discourse marker“you know”from the perspective of Relevance Theory based on the dialogues of Season 3 in The Big Bang Theory,in order to help communicators understand and produce utterances better and then achieve successful communication.

  9. 修辞在人物性格刻画中的作用──以《生活大爆炸》中的对白为例%The Function of Rhetoric in Character Depiction——Taking Dialogues from The Big Bang Theory as an Example

    Institute of Scientific and Technical Information of China (English)

    陈大方

    2011-01-01

    《:生活大爆炸》是时下非常风靡的一部以"科学天才"为背景的情景喜剧,该片荣获了包括TCA奖和艾美奖在内的多个奖项。本文尝试从修辞的视域出发,分析人物对白中的修辞手法,如反语、曲解、反问、用典等,从而剖析其在人物性格刻画中的作用。%The Big Bang Theory is a very popular situation comedy nowadays with "science talent" as its background.This play has won several honors including TCA and Emmy.This paper intends to analyze from the perspective of rhetoric,analyzing the rhetorical devices of character's dialogues,such as irony,perversion,rhetorical questions,allusion,etc.as a way to anatomize character personality.

  10. Modeling and processing for next-generation big-data technologies with applications and case studies

    CERN Document Server

    Barolli, Leonard; Barolli, Admir; Papajorgji, Petraq

    2015-01-01

    This book covers the latest advances in Big Data technologies and provides the readers with a comprehensive review of the state-of-the-art in Big Data processing, analysis, analytics, and other related topics. It presents new models, algorithms, software solutions and methodologies, covering the full data cycle, from data gathering to their visualization and interaction, and includes a set of case studies and best practices. New research issues, challenges and opportunities shaping the future agenda in the field of Big Data are also identified and presented throughout the book, which is intended for researchers, scholars, advanced students, software developers and practitioners working at the forefront in their field.

  11. Reheating the Standard Model from a Hidden Sector

    CERN Document Server

    Tenkanen, Tommi

    2016-01-01

    We consider a scenario where the inflaton decays to a hidden sector thermally decoupled from the visible Standard Model sector. A tiny portal coupling between the hidden and the visible sectors later heats the visible sector so that the Standard Model degrees of freedom come to dominate the energy density of the Universe before Big Bang Nucleosynthesis. We find that this scenario is viable, although obtaining the correct dark matter abundance and retaining successful Big Bang Nucleosynthesis is not obvious. We also show that the isocurvature perturbations constituted by a primordial Higgs condensate are not problematic for the viability of the scenario.

  12. Reheating the Standard Model from a hidden sector

    Science.gov (United States)

    Tenkanen, Tommi; Vaskonen, Ville

    2016-10-01

    We consider a scenario where the inflaton decays to a hidden sector thermally decoupled from the visible Standard Model sector. A tiny portal coupling between the hidden and the visible sectors later heats the visible sector so that the Standard Model degrees of freedom come to dominate the energy density of the Universe before big bang nucleosynthesis. We find that this scenario is viable, although obtaining the correct dark matter abundance and retaining successful big bang nucleosynthesis is not obvious. We also show that the isocurvature perturbations constituted by a primordial Higgs condensate are not problematic for the viability of the scenario.

  13. Anger and hostility from the perspective of the Big Five personality model.

    Science.gov (United States)

    Sanz, Jesús; García-Vera, María Paz; Magán, Inés

    2010-06-01

    This study was aimed at examining the relationships of the personality dimensions of the five-factor model or Big Five with trait anger and with two specific traits of hostility (mistrust and confrontational attitude), and identifying the similarities and differences between trait anger and hostility in the framework of the Big Five. In a sample of 353 male and female adults, the Big Five explained a significant percentage of individual differences in trait anger and hostility after controlling the effects due to the relationship between both constructs and content overlapping across scales. In addition, trait anger was primarily associated with neuroticism, whereas mistrust and confrontational attitude were principally related to low agreeableness. These findings are discussed in the context of the anger-hostility-aggression syndrome and the capability of the Big Five for organizing and clarifying related personality constructs.

  14. New 'bigs' in cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Yurov, Artyom V. [I. Kant Russian State University, Theoretical Physics Department, 14 Al. Nevsky St., Kaliningrad 236041 (Russian Federation); Martin-Moruno, Prado [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)]. E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es

    2006-12-18

    This paper contains a detailed discussion on new cosmic solutions describing the early and late evolution of a universe that is filled with a kind of dark energy that may or may not satisfy the energy conditions. The main distinctive property of the resulting space-times is that they make to appear twice the single singular events predicted by the corresponding quintessential (phantom) models in a manner which can be made symmetric with respect to the origin of cosmic time. Thus, big bang and big rip singularity are shown to take place twice, one on the positive branch of time and the other on the negative one. We have also considered dark energy and phantom energy accretion onto black holes and wormholes in the context of these new cosmic solutions. It is seen that the space-times of these holes would then undergo swelling processes leading to big trip and big hole events taking place on distinct epochs along the evolution of the universe. In this way, the possibility is considered that the past and future be connected in a non-paradoxical manner in the universes described by means of the new symmetric solutions.

  15. The changing model of big pharma: impact of key trends.

    Science.gov (United States)

    Gautam, Ajay; Pan, Xiaogang

    2016-03-01

    Recent years have seen exciting breakthroughs in biomedical sciences that are producing truly novel therapeutics for unmet patient needs. However, the pharmaceutical industry is also facing significant barriers in the form of pricing and reimbursement, continued patent expirations and challenging market dynamics. In this article, we have analyzed data from the 1995-2015 period, on key aspects such as revenue distribution, research units, portfolio mix and emerging markets to identify four key trends that help to understand the change in strategic focus, realignment of R&D footprint, the shift from primary care toward specialty drugs and biologics and the growth of emerging markets as major revenue drivers for big pharma.

  16. An Evaluation of Evaluative Personality Terms: A Comparison of the Big Seven and Five-Factor Model in Predicting Psychopathology

    Science.gov (United States)

    Durrett, Christine; Trull, Timothy J.

    2005-01-01

    Two personality models are compared regarding their relationship with personality disorder (PD) symptom counts and with lifetime Axis I diagnoses. These models share 5 similar domains, and the Big 7 model also includes 2 domains assessing self-evaluation: positive and negative valence. The Big 7 model accounted for more variance in PDs than the…

  17. HADOOP+Big Data: Analytics Using Series Queue with Blocking Model

    Directory of Open Access Journals (Sweden)

    S. Koteeswaran

    2014-07-01

    Full Text Available Big data deals with large volumes of tons and tons of data. Since managing this much amount of data is not in the mere way for the traditional data mining techniques. Technology is in the world of pervasive environment i.e., technology follows up with its tremendous growth. Hence coordinating these amount of data in a linear way is mere little difficult, hence we proposed a new scheme in order to draw the data and data transformation in large data base. We extended our work in HADOOP (one of the big data managing tool. Our model is fully based on aggregation of data and data modelling. Our proposed model leads to high end data transformation for big data processing. We achieved our analytical result by applying our model with 2 HADOOP clusters, 4 nodes and with 25 jobs in MR functionality.

  18. The nature and structure of correlations among Big Five ratings: the halo-alpha-beta model.

    Science.gov (United States)

    Anusic, Ivana; Schimmack, Ulrich; Pinkus, Rebecca T; Lockwood, Penelope

    2009-12-01

    In light of consistently observed correlations among Big Five ratings, the authors developed and tested a model that combined E. L. Thorndike's (1920) general evaluative bias (halo) model and J. M. Digman's (1997) higher order personality factors (alpha and beta) model. With 4 multitrait-multimethod analyses, Study 1 revealed moderate convergent validity for alpha and beta across raters, whereas halo was mainly a unique factor for each rater. In Study 2, the authors showed that the halo factor was highly correlated with a validated measure of evaluative biases in self-ratings. Study 3 showed that halo is more strongly correlated with self-ratings of self-esteem than self-ratings of the Big Five, which suggests that halo is not a mere rating bias but actually reflects overly positive self-evaluations. Finally, Study 4 demonstrated that the halo bias in Big Five ratings is stable over short retest intervals. Taken together, the results suggest that the halo-alpha-beta model integrates the main findings in structural analyses of Big Five correlations. Accordingly, halo bias in self-ratings is a reliable and stable bias in individuals' perceptions of their own attributes. Implications of the present findings for the assessment of Big Five personality traits in monomethod studies are discussed.

  19. Conversion of the Big Hill geological site characterization report to a three-dimensional model.

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Joshua S.; Rautman, Christopher Arthur

    2003-02-01

    The Big Hill salt dome, located in southeastern Texas, is home to one of four underground oil-storage facilities managed by the U. S. Department of Energy Strategic Petroleum Reserve (SPR) Program. Sandia National Laboratories, as the geotechnical advisor to the SPR, conducts site-characterization investigations and other longer-term geotechnical and engineering studies in support of the program. This report describes the conversion of two-dimensional geologic interpretations of the Big Hill site into three-dimensional geologic models. The new models include the geometry of the salt dome, the surrounding sedimentary units, mapped faults, and the 14 oil storage caverns at the site. This work provides a realistic and internally consistent geologic model of the Big Hill site that can be used in support of future work.

  20. Modeling regeneration responses of big sagebrush (Artemisia tridentata) to abiotic conditions

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Ecosystems dominated by big sagebrush, Artemisia tridentata Nuttall (Asteraceae), which are the most widespread ecosystems in semiarid western North America, have been affected by land use practices and invasive species. Loss of big sagebrush and the decline of associated species, such as greater sage-grouse, are a concern to land managers and conservationists. However, big sagebrush regeneration remains difficult to achieve by restoration and reclamation efforts and there is no regeneration simulation model available. We present here the first process-based, daily time-step, simulation model to predict yearly big sagebrush regeneration including relevant germination and seedling responses to abiotic factors. We estimated values, uncertainty, and importance of 27 model parameters using a total of 1435 site-years of observation. Our model explained 74% of variability of number of years with successful regeneration at 46 sites. It also achieved 60% overall accuracy predicting yearly regeneration success/failure. Our results identify specific future research needed to improve our understanding of big sagebrush regeneration, including data at the subspecies level and improved parameter estimates for start of seed dispersal, modified wet thermal-time model of germination, and soil water potential influences. We found that relationships between big sagebrush regeneration and climate conditions were site specific, varying across the distribution of big sagebrush. This indicates that statistical models based on climate are unsuitable for understanding range-wide regeneration patterns or for assessing the potential consequences of changing climate on sagebrush regeneration and underscores the value of this process-based model. We used our model to predict potential regeneration across the range of sagebrush ecosystems in the western United States, which confirmed that seedling survival is a limiting factor, whereas germination is not. Our results also suggested that modeled

  1. On Subtitle Translation Strategies From the Perspective of Relevance Theory:A Case Study of The Big Bang Theory%关联理论视角下的字幕翻译策略--以《生活大爆炸》为例

    Institute of Scientific and Technical Information of China (English)

    张文珍

    2013-01-01

    Since the international dissemination of movie and TV plays relies on subtitle translation, it is essential for us to make a dedicated research into the related translation strategies , considering the unique particularities of the language of such translation versions .Relevance Theory argues that a successful communication allows the audience to achieve maximum con-textual effects with minimum processing efforts, which is exactly the expected result of subtitle translation.Hence, guiding un-der the Relevance Theory, the paper explores the translation strategies embodied in the subtitles of the blockbuster The Big Bang Theory, hoping to facilitate the future translation of subtitles.%  影视作品的跨国界传播有赖于字幕翻译,影视语言又具有其特殊性,这就给字幕翻译提出了特殊要求,有必要就此展开专门研究。关联理论认为,判断交际行为成功与否取决于听话者是否通过付出最小努力获得最大语境效果,这正是字幕翻译所应追求的。故笔者以关联理论为指导,从“双关语翻译”、“情绪表达翻译”、“文化词语翻译”三个维度,探索热播美剧《生活大爆炸》中的字幕翻译策略,以期有助于日后的字幕翻译工作。

  2. A Fourier dimensionality reduction model for big data interferometric imaging

    CERN Document Server

    Kartik, S Vijay; Thiran, Jean-Philippe; Wiaux, Yves

    2016-01-01

    Data dimensionality reduction in radio interferometry can provide critical savings of computational resources for image reconstruction, which is of paramount importance for the scalability of imaging methods to the big data setting of the next-generation telescopes. This article sheds new light on dimensionality reduction from the perspective of the compressed sensing theory and studies its interplay with imaging algorithms designed in the context of convex optimization. We propose a post-gridding linear data embedding to the space spanned by the left singular vectors of the measurement operator, providing a dimensionality reduction below image size. This embedding preserves the null space of the measurement operator and hence its sampling properties are also preserved in light of the compressed sensing theory. We show that this can be approximated by first computing the dirty image and then applying a weighted subsampled discrete Fourier transform to obtain the final reduced data vector. This Fourier dimensi...

  3. Bang-bang control of feeding: role of hypothalamic and satiety signals.

    Directory of Open Access Journals (Sweden)

    B Silvano Zanutto

    2007-05-01

    Full Text Available Rats, people, and many other omnivores eat in meals rather than continuously. We show by experimental test that eating in meals is regulated by a simple bang-bang control system, an idea foreshadowed by Le Magnen and many others, shown by us to account for a wide range of behavioral data, but never explicitly tested or tied to neurophysiological facts. The hypothesis is simply that the tendency to eat rises with time at a rate determined by satiety signals. When these signals fall below a set point, eating begins, in on-off fashion. The delayed sequelae of eating increment the satiety signals, which eventually turn eating off. Thus, under free conditions, the organism eats in bouts separated by noneating activities. We report an experiment with rats to test novel predictions about meal patterns that are not explained by existing homeostatic approaches. Access to food was systematically but unpredictably interrupted just as the animal tried to start a new meal. A simple bang-bang model fits the resulting meal-pattern data well, and its elements can be identified with neurophysiological processes. Hypothalamic inputs can provide the set point for longer-term regulation carried out by a comparator in the hindbrain. Delayed gustatory and gastrointestinal aftereffects of eating act via the nucleus of the solitary tract and other hindbrain regions as neural feedback governing short-term regulation. In this way, the model forges real links between a functioning feedback mechanism, neuro-hormonal data, and both short-term (meals and long-term (eating-rate regulation behavioral data.

  4. Loop quantum cosmology of Bianchi type IX models

    CERN Document Server

    Wilson-Ewing, Edward

    2010-01-01

    The loop quantum cosmology "improved dynamics" of the Bianchi type IX model are studied. The action of the Hamiltonian constraint operator is obtained via techniques developed for the Bianchi type I and type II models, no new input is required. It is shown that the big bang and big crunch singularities are resolved by quantum gravity effects. We also present the effective equations which provide modifications to the classical equations of motion due to quantum geometry effects.

  5. Loop quantum cosmology of Bianchi type IX models

    Science.gov (United States)

    Wilson-Ewing, Edward

    2010-08-01

    The loop quantum cosmology “improved dynamics” of the Bianchi type IX model are studied. The action of the Hamiltonian constraint operator is obtained via techniques developed for the Bianchi type I and type II models, no new input is required. It is shown that the big bang and big crunch singularities are resolved by quantum gravity effects. We also present effective equations which provide quantum geometry corrections to the classical equations of motion.

  6. Comparing modelling techniques when designing VPH gratings for BigBOSS

    Science.gov (United States)

    Poppett, Claire; Edelstein, Jerry; Lampton, Michael; Jelinsky, Patrick; Arns, James

    2012-09-01

    BigBOSS is a Stage IV Dark Energy instrument based on the Baryon Acoustic Oscillations (BAO) and Red Shift Distortions (RSD) techniques using spectroscopic data of 20 million ELG and LRG galaxies at 0.5VPH) gratings have been identified as a key technology which will enable the efficiency requirement to be met, however it is important to be able to accurately predict their performance. In this paper we quantitatively compare different modelling techniques in order to assess the parameter space over which they are more capable of accurately predicting measured performance. Finally we present baseline parameters for grating designs that are most suitable for the BigBOSS instrument.

  7. Honesty-humility, the big five, and the five-factor model.

    Science.gov (United States)

    Ashton, Michael C; Lee, Kibeom

    2005-10-01

    This study investigated the relations of the proposed sixth factor of personality, Honesty-Humility, with the dimensions of the classic English lexical Big Five and the closely related Five-Factor Model (FFM). Results showed that although Honesty-Humility was largely unrelated to markers of the Big Five factors, it was substantially correlated with the FFM Agreeableness domain. This relation was largely due to the Straightforwardness and Modesty facets of FFM Agreeableness, which were only weakly correlated with the Big Five version of Agreeableness. A realignment of FFM facets to produce separate Honesty-Humility and Agreeableness factors provided better prediction of personality variables that involve deceit without hostility, such as Social Adroitness and Self-Monitoring. Results indicate the importance of assessing Honesty-Humility as a separate factor.

  8. Modeling canopy-level productivity: is the "big-leaf" simplification acceptable?

    Science.gov (United States)

    Sprintsin, M.; Chen, J. M.

    2009-05-01

    The "big-leaf" approach to calculating the carbon balance of plant canopies assumes that canopy carbon fluxes have the same relative responses to the environment as any single unshaded leaf in the upper canopy. Widely used light use efficiency models are essentially simplified versions of the big-leaf model. Despite its wide acceptance, subsequent developments in the modeling of leaf photosynthesis and measurements of canopy physiology have brought into question the assumptions behind this approach showing that big leaf approximation is inadequate for simulating canopy photosynthesis because of the additional leaf internal control on carbon assimilation and because of the non-linear response of photosynthesis on leaf nitrogen and absorbed light, and changes in leaf microenvironment with canopy depth. To avoid this problem a sunlit/shaded leaf separation approach, within which the vegetation is treated as two big leaves under different illumination conditions, is gradually replacing the "big-leaf" strategy, for applications at local and regional scales. Such separation is now widely accepted as a more accurate and physiologically based approach for modeling canopy photosynthesis. Here we compare both strategies for Gross Primary Production (GPP) modeling using the Boreal Ecosystem Productivity Simulator (BEPS) at local (tower footprint) scale for different land cover types spread over North America: two broadleaf forests (Harvard, Massachusetts and Missouri Ozark, Missouri); two coniferous forests (Howland, Maine and Old Black Spruce, Saskatchewan); Lost Creek shrubland site (Wisconsin) and Mer Bleue petland (Ontario). BEPS calculates carbon fixation by scaling Farquhar's leaf biochemical model up to canopy level with stomatal conductance estimated by a modified version of the Ball-Woodrow-Berry model. The "big-leaf" approach was parameterized using derived leaf level parameters scaled up to canopy level by means of Leaf Area Index. The influence of sunlit

  9. Gossip Management at Universities Using Big Data Warehouse Model Integrated with a Decision Support System

    Directory of Open Access Journals (Sweden)

    Pelin Vardarlier

    2016-01-01

    Full Text Available Big Data has recently been used for many purposes like medicine, marketing and sports. It has helped improve management decisions. However, for almost each case a unique data warehouse should be built to benefit from the merits of data mining and Big Data. Hence, each time we start from scratch to form and build a Big Data Warehouse. In this study, we propose a Big Data Warehouse and a model for universities to be used for information management, to be more specific gossip management. The overall model is a decision support system that may help university administraitons when they are making decisions and also provide them with information or gossips being circulated among students and staff. In the model, unsupervised machine learning algorithms have been employed. A prototype of the proposed system has also been presented in the study. User generated data has been collected from students in order to learn gossips and students’ problems related to school, classes, staff and instructors. The findings and results of the pilot study suggest that social media messages among students may give important clues for the happenings at school and this information may be used for management purposes.The model may be developed and implemented by not only universities but also some other organisations.

  10. A New Look at the Big Five Factor Structure through Exploratory Structural Equation Modeling

    Science.gov (United States)

    Marsh, Herbert W.; Ludtke, Oliver; Muthen, Bengt; Asparouhov, Tihomir; Morin, Alexandre J. S.; Trautwein, Ulrich; Nagengast, Benjamin

    2010-01-01

    NEO instruments are widely used to assess Big Five personality factors, but confirmatory factor analyses (CFAs) conducted at the item level do not support their a priori structure due, in part, to the overly restrictive CFA assumptions. We demonstrate that exploratory structural equation modeling (ESEM), an integration of CFA and exploratory…

  11. Response of harmonically and stochastically excited strongly nonlinear oscillators with delayed feedback bang-bang control

    Institute of Scientific and Technical Information of China (English)

    Chang-shui FENG; Wei-qiu ZHU

    2009-01-01

    We studied the response of harmonically and stochastically excited strongly nonlinear oscillators with delayed feedback bang-bang control using the stochastic averaging method. First, the time-delayed feedback bang-bang control force is expressed approximately in terms of the system state variables without time delay. Then the averaged Ito stochastic differential equations for the system are derived using the stochastic averaging method. Finally, the response of the system is obtained by solving the Fokker-Plank-Kolmogorov (FPK) equation associated with the averaged Ito equations. A Duffing oscillator with time-delayed feedback bang-bang control under combined harmonic and white noise excitations is taken as an example to illus-trate the proposed method. The analytical results are confirmed by digital simulation. We found that the time delay in feedback bang-bang control will deteriorate the control effectiveness and cause bifurcation of stochastic jump of Duffing oscillator.

  12. 科学情景喜剧人物设置特性分析--以《生活大爆炸》为例%Characteristics of the Character Establishment of Science Sitcom:A Case Study on The Big Bang Theory

    Institute of Scientific and Technical Information of China (English)

    卿婉莹

    2013-01-01

    Since it was presented, Ameri can science sitcom The Big Bang Theory has been widely appreciated by the audience,including critics and real scientists. Focused on young scientists,the TV play has created an individual style of science sitcom through the integration of science and daily life. Compared with ordinary themes, the science sitcom sets three particular kinds of character relations to advance the story on the background of science. By presenting the differences of the understanding of science,differences and contradictions among scientists and connections with science fiction,the particular character establishment of science sitcom could be enlightenment for science communication.%美国科学情景喜剧《生活大爆炸》自推出以来,受到了观众及电视界、科学界的各方好评。该剧以青年科学家为人物核心,将深奥的科学理论、晦涩的科学语言、独特的科学场景与日常生活有机结合,开创出独特的科学情景喜剧风格。相较于一般体裁的情景喜剧,关注“科学”题材的《生活大爆炸》为了解决如何让“呆板、严肃的科学”吸引人而又保证其品质格调的问题,主创人员在影视剧常规创作的基础上精心设置了三组人物关系,紧扣“科学”话题,通过科学家与其他人物之间的各种冲突推动幽默剧情不断发展。构建知识差异的矛盾、讲述科学家之间的分歧、用科幻架起沟通的桥梁,科学情景喜剧中独特的人物设置对科学传播具有启发意义。

  13. 《生活大爆炸》中艺术语言的陌生化%Defamiliar Language and its Translation in "The big bang Theory"

    Institute of Scientific and Technical Information of China (English)

    王馥沁; 张璘

    2012-01-01

    陌生化是俄国形式主义理论关于艺术创作的重要思想。在形式主义看来,艺术的过程就是使事物"陌生化",打破常识常规,延长审美,使人产生新鲜陌生感。《生活大爆炸》作为一部另类的情景喜剧,其艺术语言的运用独辟蹊径,别具匠心。本文从陌生化角度分析影片中的幽默语言、视听语言、造型语言等影视艺术语言的运用,深入探析其独特创新之处,阐释其偏离生活常态而产生的另类美感。%Defamiliarization is an important theory of Russian formalism. In the formalism, the process of " Defamiliarization " is to make the object strange . Therefore , Situational comedy, as a form of the art, is lacking in the analysis of Defamiliar Language use . From the aspect of defamiliarization ,this article analyses the humorous language,visual language, the model language and other artistic language film, deeply to improve the subsequent TV development trend and to provide a reasonable conception and prediction.

  14. Methodological challenges and analytic opportunities for modeling and interpreting Big Healthcare Data.

    Science.gov (United States)

    Dinov, Ivo D

    2016-01-01

    Managing, processing and understanding big healthcare data is challenging, costly and demanding. Without a robust fundamental theory for representation, analysis and inference, a roadmap for uniform handling and analyzing of such complex data remains elusive. In this article, we outline various big data challenges, opportunities, modeling methods and software techniques for blending complex healthcare data, advanced analytic tools, and distributed scientific computing. Using imaging, genetic and healthcare data we provide examples of processing heterogeneous datasets using distributed cloud services, automated and semi-automated classification techniques, and open-science protocols. Despite substantial advances, new innovative technologies need to be developed that enhance, scale and optimize the management and processing of large, complex and heterogeneous data. Stakeholder investments in data acquisition, research and development, computational infrastructure and education will be critical to realize the huge potential of big data, to reap the expected information benefits and to build lasting knowledge assets. Multi-faceted proprietary, open-source, and community developments will be essential to enable broad, reliable, sustainable and efficient data-driven discovery and analytics. Big data will affect every sector of the economy and their hallmark will be 'team science'.

  15. A model of self-actualization:A Psychobiography Study of Liu Bang's Personality T raits%自我实现者的典范--刘邦自我实现人格的心理传记分析

    Institute of Scientific and Technical Information of China (English)

    舒跃育

    2015-01-01

    Liu Bang is a model of self‐actualization among the political figures . Through analysis and comparison of the nine founding emperors' family backgrounds , birth order , childhood and experiences of education ,and the way to power and ruling time , this paper finds that under limited circumstances Liu Bang achieved his self‐potential to the greatest extent . He not only went beyond himself and changed history ,but also surpassed the limits of human nature .These can be attributed to his personality traits of self‐actualization .%刘邦是政治人物中的自我实现者的典范。研究通过对九位开国帝王的出身、家庭排行、幼年经历与教育情况、获得政权方式、登基时间、在位时间的分析比较发现,相对其他八位开国帝王而言,刘邦是在各方面条件极其受限的情况下,实现了自己潜能最大程度的发挥,他不仅超越了自我、改变了历史,同时也突破了人性的限制。而他对这些限制的突破,源自他诸多自我实现的人格特征。

  16. Big Data: Big Confusion? Big Challenges?

    Science.gov (United States)

    2015-05-01

    12th Annual Acquisition Research Symposium 12th Annual Acquisition Research Symposium Big Data : Big Confusion? Big Challenges? Mary Maureen... Data : Big Confusion? Big Challenges? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...Acquisition Research Symposium • ~!& UNC CHARlD1TE 90% of the data in the world today was created in the last two years Big Data growth from

  17. Big Surveys, Big Data Centres

    Science.gov (United States)

    Schade, D.

    2016-06-01

    Well-designed astronomical surveys are powerful and have consistently been keystones of scientific progress. The Byurakan Surveys using a Schmidt telescope with an objective prism produced a list of about 3000 UV-excess Markarian galaxies but these objects have stimulated an enormous amount of further study and appear in over 16,000 publications. The CFHT Legacy Surveys used a wide-field imager to cover thousands of square degrees and those surveys are mentioned in over 1100 publications since 2002. Both ground and space-based astronomy have been increasing their investments in survey work. Survey instrumentation strives toward fair samples and large sky coverage and therefore strives to produce massive datasets. Thus we are faced with the "big data" problem in astronomy. Survey datasets require specialized approaches to data management. Big data places additional challenging requirements for data management. If the term "big data" is defined as data collections that are too large to move then there are profound implications for the infrastructure that supports big data science. The current model of data centres is obsolete. In the era of big data the central problem is how to create architectures that effectively manage the relationship between data collections, networks, processing capabilities, and software, given the science requirements of the projects that need to be executed. A stand alone data silo cannot support big data science. I'll describe the current efforts of the Canadian community to deal with this situation and our successes and failures. I'll talk about how we are planning in the next decade to try to create a workable and adaptable solution to support big data science.

  18. A Big Bang or small bangs? Effects of biotic environment on hatching

    Directory of Open Access Journals (Sweden)

    Marina MANCA

    2008-08-01

    Full Text Available The beginning and end of diapause are two important transition points in cladoceran life history. The influence of environmental variables on the dynamics of these processes still deserves attention, especially as concerns the role of biotic factors. In this paper we focus on emergence from diapause, testing (1 whether ephippia of Daphnia obtusa Kurz can assess the presence in the water of typical planktivorous fish or ostracods, and (2 whether such an assessment results in changes in hatching strategy. Total number of hatchlings from D. obtusa ephippial eggs did not differ between the control and the treatments in which the presence of fish or ostracods could be detected (ANOVA, P = 0.884. However, hatching dynamics were different: most of the eggs hatched synchronously at day 4 (83.3% of the total hatchlings number in the control, while only a low proportion of eggs hatched on day 4 in the fish (38.3%, and ostracod treatments (24.0% of the total. Mean hatching time was longer, and variability larger, in the treatments than in the control; differences resulted statistically significant (ANOVA, P = 0.005. With respect to the control, representing a simple microcosm controlled by abiotic variables only, the treatments may be regarded as relatively complex environments, in which Daphnia is also exposed to biotic cues. Under these more complex conditions, the same number of hatchlings is obtained through different hatching dynamics. In the treatments, the first hatchlings appeared later and the hatching rate was more variable than in the control. These observations confirm previously observed patterns from laboratory experiments which tested the effect of competition and fluctuating environmental conditions (light:dark, temperature regimes on D. obtusa reproductive and demographic parameters. They are also in agreement with recently obtained evidence concerning the importance of biotic cues for hatching of ephippial eggs. Overall, the evidence suggests that Daphnia can detect infochemicals during dormancy. Specifically, we propose that the presence in the water medium of potential predators and competitors results in a short-term hatching asynchrony of ephippial eggs.

  19. A critical review of lexical analysis and Big Five model

    Directory of Open Access Journals (Sweden)

    María Cristina Richaud de Minzi

    2002-06-01

    Full Text Available In the last years the idea has resurfaced that traits can be measured in a reliable and valid and this can be useful inthe prediction of human behavior. The five-factor model appears to represent a conceptual and empirical advances in the field of personality theory. Necessary orthogonal factors (Goldberg, 1992, p. 26 to show the relationships between the descriptors of the features in English is five, and its nature can be summarized through the broad concepts of Surgency, Agreeableness, Responsibility, Emotional Stability versus neuroticism and openness to experience (John, 1990, p96 Furthermore, despite the criticisms that have been given to the model, represents a breakthrough in the field of personality assessment. This approach means a contribution to the study of personality, without being the integrative model of personality.

  20. Metabolic modeling with Big Data and the gut microbiome.

    Science.gov (United States)

    Sung, Jaeyun; Hale, Vanessa; Merkel, Annette C; Kim, Pan-Jun; Chia, Nicholas

    2016-09-01

    The recent advances in high-throughput omics technologies have enabled researchers to explore the intricacies of the human microbiome. On the clinical front, the gut microbial community has been the focus of many biomarker-discovery studies. While the recent deluge of high-throughput data in microbiome research has been vastly informative and groundbreaking, we have yet to capture the full potential of omics-based approaches. Realizing the promise of multi-omics data will require integration of disparate omics data, as well as a biologically relevant, mechanistic framework - or metabolic model - on which to overlay these data. Also, a new paradigm for metabolic model evaluation is necessary. Herein, we outline the need for multi-omics data integration, as well as the accompanying challenges. Furthermore, we present a framework for characterizing the ecology of the gut microbiome based on metabolic network modeling.

  1. Teaching the Big Ideas of Biology with Operon Models

    Science.gov (United States)

    Cooper, Robert A.

    2015-01-01

    This paper presents an activity that engages students in model-based reasoning, requiring them to predict the behavior of the trp and lac operons under different environmental conditions. Students are presented six scenarios for the "trp" operon and five for the "lac" operon. In most of the scenarios, specific mutations have…

  2. Big bang or continuous creation: does life have multiple origins?

    Science.gov (United States)

    Konesky, Gregory A.

    2012-10-01

    The generally accepted notion of a single origin of life from a primordial soup on the early Earth has been challenged recently by the suggestion of a "second life," "shadow life," and even "biological dark matter." The problem in classifying these microorganisms is in the difficulty or complete failure of the 16s genetic fingerprinting process, suggesting a different underlying biochemistry resulting from at least a second origin of life. We consider an extension of this concept to include continuous origination of life throughout Earth's history, up to the present. The consequences for interpreting the "tree of life" are also considered.

  3. All the makings of a resounding Big Bang

    CERN Multimedia

    Thomas, Paul J

    2008-01-01

    "As their communications team has demnstrated, CERN's Large Hadron Collider is capable of more than worrying us over mini black holes; rather, it brings both scientists and the public together to celebrate human progress." (3 pages)

  4. Mass Boom Versus Big Bang Einstein was Right

    CERN Document Server

    Alfonso-Faus, A

    2003-01-01

    When considering possible time variations of fundamental physical constants one has to keep firm well established principles. Following this approach we keep firm the Action Principle, General Relativity (the Equivalence Principle), and Mach's Principle. Also we introduce a new principle under the name of "TOTAL INTERACTION" and reconsider Weinberg's relation with a new approach. Consistent with all these principles we find that all masses increase linearly with cosmological time (THE MASS BOOM) and that Planck's constant decreases also with this time.Then the whole quantum world shrinks with time too. This is the cause of the red shift

  5. Machine readied to create "mini-Big Bangs"

    CERN Multimedia

    Lovell, Jeremy

    2006-01-01

    "Deep underground on the Franco-Swiss border, someone will throw a switch next year to start one of the most ambitious experiments in history, probing the secrets of the universe and possibly finding new dimensions." (1 page)

  6. The Big Bang or not?;The year in ideas

    CERN Multimedia

    2007-01-01

    It has been nicknamed the "God particle", and it is the keystone of modern physics. Without it, science's best explanation for the nature of the universe would come crashing down. The Higgs boson, first postulated in the Sixties by Professor Peter Higgs of Edinburgh University, is certainly among the most elegant ideas in the history of physics, but it has one small problem. Nobody knows whether it actually exists.

  7. Big bang machine searching for the Higgs boson particle

    CERN Document Server

    2015-01-01

    On July 4, 2012, scientists at the giant atom smashing facility at CERN announced the discovery of a subatomic particle that seems like a tantalizingly close match to the elusive Higgs Boson, thought to be responsible for giving all the stuff in the universe its mass. Since it was first proposed nearly fifty years ago, the Higgs has been the holy grail of particle physicists: in finding it they validate the “standard model” that underlies all of modern physics and open the door to new discoveries when CERN’s giant collider switches on at higher power in 2015.

  8. Background radiation deepens the confusion for big bang theorists

    CERN Multimedia

    Vaughan, C

    1990-01-01

    Results from COBE presented at an APS meeting in Washington this week, confirmed earlier results that revealed that matter was spread around so smoothly in the early Universe that it is difficult to explain how galaxies could have formed (1/2 page).

  9. The dual behavior of quantum Fields and the big Bang

    CERN Document Server

    Matwi, Malik

    2016-01-01

    We modify the propagation for the quarks and gluons, with that we have finite results, without ultra violet divergence in perturbed interaction of the quarks and gluons, this makes it easily for the interaction renormalization, like the self energy. Then we search for a way to remove our modification, with fixing the Lagrange parameters. so we can ignore our modification. We relate the modification to interaction situation, this is, we need it only for interaction renormalization. we see for the free the modification is removed. then We try to give the modification terms modification physical aspects, for this we see the corresponding terms in the Lagrange. To do that we find the role of those terms in the Feynman diagrams, in self energies, quarks gluons vertex. We see we can relate the propagation modification to fields dual behavior, pairing particle with antiparticle appears as scalar particles with high mass. For the quarks we can interrupt these particles as pions.

  10. Discovery of the Hot Big Bang: What happened in 1948

    CERN Document Server

    Peebles, P J E

    2013-01-01

    The idea that the universe is filled with the thermal radiation now termed the Cosmic Microwave Background was first discussed in eleven publications in the year 1948. These papers offer a detailed example of the process of development of a new and now very productive line of research, and of the confusion that can attend new ideas. The confusion in this case left a common misunderstanding of the considerations that motivated the idea of the sea of radiation.

  11. Particle accelerators from Big Bang physics to hadron therapy

    CERN Document Server

    Amaldi, Ugo

    2015-01-01

    The theoretical physicist Victor “Viki” Weisskopf, Director-General of CERN from 1961 to 1965, once “There are three kinds of physicists, namely the machine builders, the experimental physicists, and the theoretical physicists. […] The machine builders are the most important ones, because if they were not there, we would not get into this small-scale region of space. If we compare this with the discovery of America, the machine builders correspond to captains and ship builders who really developed the techniques at that time. The experimentalists were those fellows on the ships who sailed to the other side of the world and then landed on the new islands and wrote down what they saw. The theoretical physicists are those who stayed behind in Madrid and told Columbus that he was going to land in India.” Rather than focusing on the theoretical physicists, as most popular science books on particle physics do, this beautifully written and also entertaining book is different in that, firstly, the main foc...

  12. Can non-commutativity resolve the big-bang singularity?

    Energy Technology Data Exchange (ETDEWEB)

    Maceda, M.; Madore, J. [Laboratoire de Physique Theorique, Universite de Paris-Sud, Batiment 211, 91405, Orsay (France); Manousselis, P. [Department of Engineering Sciences, University of Patras, 26110, Patras (Greece); Physics Department, National Technical University, Zografou Campus, 157 80, Zografou, Athens (Greece); Zoupanos, G. [Physics Department, National Technical University, Zografou Campus, 157 80, Zografou, Athens (Greece); Theory Division, CERN, 1211, Geneva 23 (Switzerland)

    2004-08-01

    A possible way to resolve the singularities of general relativity is proposed based on the assumption that the description of space-time using commuting coordinates is not valid above a certain fundamental scale. Beyond that scale it is assumed that the space-time has non-commutative structure leading in turn to a resolution of the singularity. As a first attempt towards realizing the above programme a modification of the Kasner metric is constructed which is commutative only at large time scales. At small time scales, near the singularity, the commutation relations among the space coordinates diverge. We interpret this result as meaning that the singularity has been completely delocalized. (orig.)

  13. OPERA and MINOS Experimental Result Prove Big Bang Theory Invalid

    Science.gov (United States)

    Pressler, David E.

    2012-03-01

    The greatest error in the history of science is the misinterpretation of the Michelson-Morley Experiment. The speed of light was measured to travel at the same speed in all three directions (x, y, z axis) in ones own inertial reference system; however, c will always be measured as having an absolute different speed in all other inertial frames at different energy levels. Time slows down due to motion or a gravity field. Time is the rate of physical process. Speed = Distance/Time. If the time changes the distance must change. Therefore, BOTH mirrors must move towards the center of the interferometer and space must contract in all-three-directions; C-Space. Gravity is a C-Space condition, and is the cause of redshift in our universe-not motion. The universe is not expanding. OPERA results are directly indicated; at the surface of earth, the strength of the gravity field is at maximum-below the earth's surface, time and space is less distorted, C-Space; therefore, c is faster. Newtonian mechanics dictate that a spherical shell of matter at greater radii, with uniform density, produces no net force on an observer located centrally. An observer located on the sphere's surface, like our Earth's or a large sphere, like one located in a remote galaxy, will construct a picture centered on himself to be identical to the one centered inside the spherical shell of mass. Both observers will view the incoming radiation, emitted by the other observer, as redshifted, because they lay on each others radial line. The Universe is static and very old.

  14. Big Bang Day: 5 Particles - 2. The Quark

    CERN Multimedia

    Franck Close

    2008-01-01

    Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 2. The Quark "Three Quarks for Master Mark! Sure he hasn't got much of a bark." James Joyce's Finnegans Wake left its mark on modern physics when physicist Murray Gell Mann proposed this name for a group of hypothetical subatomic particles that were revealed in 1960 as the fundamental units of matter. Basic particles it seems are made up of even more basic units called quarks that make up 99.9% of visible material in the universe.. But why do we know so little about them? Quarks have never been seen as free particles but instead, inextricably bound together by the Strong Force that in turn holds the atomic nucleus together. This is the hardest of Nature's fundamental forces to crack, but recent theoretical advances, mean that the properties of the quark are at last being revealed.

  15. Big Bang Day: 5 Particles - 5. The Next Particle

    CERN Multimedia

    Franck Close

    2008-01-01

    Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 5. The Next Particle The "sparticle" - a super symmetric partner to all the known particles could be the answer to uniting all the known particles and their interactions under one grand theoretical pattern of activity. But how do researchers know where to look for such phenomena and how do they know if they find them? Simon Singh reviews the next particle that physicists would like to find if the current particle theories are to ring true.

  16. La révolution du Big Bang

    CERN Multimedia

    2008-01-01

    Eternal and unchanging: So was during a long time considered the Universe. Until a handle of fool-hardy dare to imagine the contrary. History of a theory that was not still so consensual. (9 pages + photos)

  17. Big Bang Day: 5 Particles - 4. The Neutrino

    CERN Multimedia

    2008-01-01

    Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". It's the most populous particle in the universe. Millions of these subatomic particles are passing through each one of us. With no charge and virtually no mass they can penetrate vast thicknesses of matter without any interaction - indeed the sun emits huge numbers that pass through earth at the speed of light. Neutrinos are similar to the more familiar electron, with one crucial difference: neutrinos do not carry electric charge. As a result they're extremely difficult to detect . But like HG Wells' invisible man they can give themselves away by bumping into things at high energy and detectors hidden in mines are exploiting this to observe these rare interactions.

  18. Galaxies in the First Billion Years After the Big Bang

    Science.gov (United States)

    Stark, Daniel P.

    2016-09-01

    In the past five years, deep imaging campaigns conducted with the Hubble Space Telescope (HST) and ground-based observatories have delivered large samples of galaxies at 6.546 UV-selected galaxies are relatively compact with blue UV continuum slopes, low stellar masses, and large specific star formation rates. In the last year, ALMA (the Atacama Large Millimeter Array) and ground-based infrared spectrographs have begun to complement this picture, revealing minimal dust obscuration and hard radiation fields, and providing evidence for metal-poor ionized gas. Weak low-ionization absorption lines suggest a patchy distribution of neutral gas surrounds O and B stars, possibly aiding in the escape of ionizing radiation. Gamma ray burst afterglows and Lyman-α surveys have provided evidence that the intergalactic medium (IGM) evolves from mostly ionized at z≃6-6.5 ([Formula: see text]) to considerably neutral at z≃7-8 ([Formula: see text]). The reionization history that emerges from considering the UV output of galaxies over 64 mag below current surveys and a moderate fraction ([Formula: see text]) of ionizing radiation escapes from galaxies.

  19. Old stars put their weight behind the big bang theory

    CERN Multimedia

    1990-01-01

    The amount of helium in the Universe depends on how many varieties of neutrino there are. Results from CERN have restricted this to three so theorists have been able to calculate how muchhelium there should be (1/2 page).

  20. The big-bang-for-your-buck theory.

    Science.gov (United States)

    Lucas, H C; Weill, P; Cox, S

    1993-01-01

    Do it right, and your investment in information technology can have all sorts of strategic payoffs. Do it wrong, and you'll be paying, dearly, for nothing. Here's a guide to evaluating IT and measuring its impact.

  1. Remembering when the big bang seemed so simple

    CERN Multimedia

    Johnson, George

    2006-01-01

    Fourteen years ago, an astronomer at Berkeley declared that he and his satellite, COBE, had detected the astrophysical equivalent of the fingerprints of God, his euphoria was easy to understand. (1 page)

  2. 李孝利爱上Big Bang

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正> 人说30岁是女人的一道坎,面对这道坎,相信很多未婚的女人都会有压力吧。潮流女王李孝利也即将要踏入30岁的关口,眼见现在仍旧孤身一人,言谈中时时显现出一颗恨嫁的心。去年很多韩国女星结婚恋爱,身为韩国

  3. Big Bang:最强炸药库

    Institute of Scientific and Technical Information of China (English)

    哈哈帮

    2009-01-01

    <正>"轰——"打雷了啊,大家赶紧收衣服啊!咦,好像不是打雷的声音,好像是哪爆炸了,啊,大家赶紧撤到安全地带啊……嗯?又好像不是爆炸的声音,那是什么啊,你不要搞得人心惶惶的啊!啊,这次不会错了,"类蒂森"and"间

  4. The Big Bang: Facial Trauma Caused by Recreational Fireworks.

    Science.gov (United States)

    Molendijk, Josher; Vervloet, Bob; Wolvius, Eppo B; Koudstaal, Maarten J

    2016-06-01

    In the Netherlands, it is a tradition of setting off fireworks to celebrate the turn of the year. In our medical facility, each year patients with severe skeletal maxillofacial trauma inflicted by recreational fireworks are encountered. We present two cases of patients with severe blast injury to the face, caused by direct impact of rockets, and thereby try to contribute to the limited literature on facial blast injuries, their treatment, and clinical outcome. These patients require multidisciplinary treatment, involving multiple reconstructive surgeries, and the overall recovery process is long. The severity of these traumas raises questions about the firework traditions and legislations not only in the Netherlands but also worldwide. Therefore, the authors support restrictive laws on personal use of fireworks in the Netherlands.

  5. Arizona State's Origins Project Starts with a Big Bang

    Science.gov (United States)

    Mangan, Katherine

    2009-01-01

    For 12 hours at Arizona State University, a sold-out crowd of 3,000 people gave a group of famous scientists a pop-star welcome, cheering their remarks and lining up for autographs after a day full of discussion about black holes, string theory, and evolutionary biology. At a time when program cuts and faculty layoffs dominate the headlines of…

  6. Fire, Aim… Ready? Alberta's Big Bang Approach to Healthcare Disintegration.

    Science.gov (United States)

    Donaldson, Cam

    2010-08-01

    Alberta's abolition in 2008 of its health regions and the creation of Alberta Health Services (AHS) was a bold move, but the reasons for the change remain hazy. The stated goals were to "help make Alberta's … system more effective and efficient" and to "provide equitable access to health services and long-term sustainability." Data show, however, that Alberta's health regions were already performing well on these goals relative to other provinces, and where changes have since occurred, they cannot necessarily be attributed to AHS.

  7. Big bang in the evolution of extant malaria parasites.

    Science.gov (United States)

    Hayakawa, Toshiyuki; Culleton, Richard; Otani, Hiroto; Horii, Toshihiro; Tanabe, Kazuyuki

    2008-10-01

    Malaria parasites (genus Plasmodium) infect all classes of terrestrial vertebrates and display host specificity in their infections. It is therefore assumed that malaria parasites coevolved intimately with their hosts. Here, we propose a novel scenario of malaria parasite-host coevolution. A phylogenetic tree constructed using the malaria parasite mitochondrial genome reveals that the extant primate, rodent, bird, and reptile parasite lineages rapidly diverged from a common ancestor during an evolutionary short time period. This rapid diversification occurred long after the establishment of the primate, rodent, bird, and reptile host lineages, which implies that host-switch events contributed to the rapid diversification of extant malaria parasite lineages. Interestingly, the rapid diversification coincides with the radiation of the mammalian genera, suggesting that adaptive radiation to new mammalian hosts triggered the rapid diversification of extant malaria parasite lineages.

  8. The Role of Antimatter in Big-Bang Cosmology

    Science.gov (United States)

    Stecker, Floyd W.

    1974-01-01

    Discusses theories underlying man's conceptions of the universe, including Omnes' repulsive separation mechanism, the turbulence theory of galaxy formation, and the author's idea about gamma ray spectra in cosmological matter-antimatter annihilation. Indicates that the Apollo data provide encouraging evidence by fitting well with his theoretical…

  9. The "Big Bang" in Public and Private Faculty Salaries

    Science.gov (United States)

    Rippner, Jennifer A.; Toutkoushian, Robert K.

    2015-01-01

    The gap between average faculty salaries at public and private institutions has been growing wider over the past 40 years, yet little is known about the nature and causes of the gap. This study uses data on more than 1,000 institutions to examine institutional average faculty salaries and how they have changed for public and private institutions.…

  10. "Big Bang" global grid moves a step closer

    CERN Multimedia

    Weiss, Todd R

    2006-01-01

    A huge 100,000-PC grid-computing network being built to help research the origin of the universe passed the third of major tests recently when it reached a data-transfer milestone, with up to 1GB/s of physics data sent over the global grid

  11. Alrededor 5000 cientificos estudiaran conjuntamente Big Bang a traves red

    CERN Multimedia

    2007-01-01

    The CERN will put in contact to 5000 scientists through an informatics network so that they can study jointly the data that the LHC will offer, an experiment that will give new paths about the origin of the universe. (1 age)

  12. Higher-order factors of the big five model of personality: a reanalysis of Digman (1997).

    Science.gov (United States)

    Mutch, Christopher

    2005-02-01

    Based on the results from factor analyses conducted on 14 different data sets, Digman proposed a model of two higher-order factors, or metatraits, that subsumed the Big Five personality traits. In the current article, problems in Digman's analyses were explicated, and more appropriate analyses were then conducted using the same 14 correlation matrices from Digman's study. The resultant two-factor model produced improper solutions, poor model fit indices, or both, in almost all of the 14 data sets and thus raised serious doubts about the veracity of Digman's proposed model.

  13. A Review on Large Scale Graph Processing Using Big Data Based Parallel Programming Models

    Directory of Open Access Journals (Sweden)

    Anuraj Mohan

    2017-02-01

    Full Text Available Processing big graphs has become an increasingly essential activity in various fields like engineering, business intelligence and computer science. Social networks and search engines usually generate large graphs which demands sophisticated techniques for social network analysis and web structure mining. Latest trends in graph processing tend towards using Big Data platforms for parallel graph analytics. MapReduce has emerged as a Big Data based programming model for the processing of massively large datasets. Apache Giraph, an open source implementation of Google Pregel which is based on Bulk Synchronous Parallel Model (BSP is used for graph analytics in social networks like Facebook. This proposed work is to investigate the algorithmic effects of the MapReduce and BSP model on graph problems. The triangle counting problem in graphs is considered as a benchmark and evaluations are made on the basis of time of computation on the same cluster, scalability in relation to graph and cluster size, resource utilization and the structure of the graph.

  14. Position of aggressiveness in common latent space of PEN model and model Big Five Plus Two

    Directory of Open Access Journals (Sweden)

    Dinić Bojana

    2012-01-01

    Full Text Available The purpose of this research was to examine the relations between different aspects of aggressiveness and personality traits. Buss-Perry Aggression Questionnaire (AQ, Eysenck Personality Questionnaire (EPQ, which represent psychobiological model, and inventory Big Five Plus Two Inventory (BF+2, which represent psycholexical model of personality in Serbian language, were administered to 478 participants. The results revealed that affective impulsive aggressiveness and predatory or instrumental aggressiveness could be identified in the aggressiveness - personality traits relationships. Those aspects of aggressiveness could take manifest or latent character. As expected, Psychoticism from EPQ, Aggressiveness, and Negative Valence from BF+2 showed a significant contribution to all identified forms, except for Aggressiveness in relations with “acting out” physical aggression. Although these personality traits carry out significant loadings, these loadings were not always the highest. Affective-impulsive aggressiveness, which was mainly determined by the components of latent domain AQ, was related to Neuroticism from both models. The remaining forms of manifest aggressiveness were related to low Consciousness, whereas Physical aggression is connected to Extraversion and Oppennes. This connection represents possible “acting out” reaction or more frequent tendency of impulsive physical aggression. The results showed that aggressiveness represents a multidimensional construct which could be explained by specific constellation of personality traits, depending which aspects of aggressivenes are of interest. [Projekat Ministarstva nauke Republike Srbije, br. ON179006: Nasledni, sredinski i psihološki činioci mentalnog zdravlja

  15. Simulation and Big Data Challenges in Tuning Building Energy Models

    Energy Technology Data Exchange (ETDEWEB)

    Sanyal, Jibonananda [ORNL; New, Joshua Ryan [ORNL

    2013-01-01

    EnergyPlus is the flagship building energy simulation software used to model whole building energy consumption for residential and commercial establishments. A typical input to the program often has hundreds, sometimes thousands of parameters which are typically tweaked by a buildings expert to get it right . This process can sometimes take months. Autotune is an ongoing research effort employing machine learning techniques to automate the tuning of the input parameters for an EnergyPlus input description of a building. Even with automation, the computational challenge faced to run the tuning simulation ensemble is daunting and requires the use of supercomputers to make it tractable in time. In this proposal, we describe the scope of the problem, the technical challenges faced and overcome, the machine learning techniques developed and employed, and the software infrastructure developed/in development when taking the EnergyPlus engine, which was primarily designed to run on desktops, and scaling it to run on shared memory supercomputers (Nautilus) and distributed memory supercomputers (Frost and Titan). The parametric simulations produce data in the order of tens to a couple of hundred terabytes.We describe the approaches employed to streamline and reduce bottlenecks in the workflow for this data, which is subsequently being made available for the tuning effort as well as made available publicly for open-science.

  16. BIG DATA-Related Challenges and Opportunities in Earth System Modeling

    Science.gov (United States)

    Bamzai, A. S.

    2012-12-01

    Knowledge of the Earth's climate has increased immensely in recent decades, both through observational analysis and modeling. BIG DATA-related challenges emerge in our quest for understanding the variability and predictability of the climate and earth system on a range of time scales, as well as in our endeavor to improve predictive capability using state-of-the-science models. To enable further scientific discovery, bottlenecks in current paradigms need to be addressed. An overview of current NSF activities in Earth System Modeling with a focus on associated data-related challenges and opportunities, will be presented.

  17. A Class of LQC--inspired Models for Homogeneous, Anisotropic Cosmology in Higher Dimensional Early Universe

    CERN Document Server

    Rama, S Kalyana

    2016-01-01

    The dynamics of a (3 + 1) dimensional homogeneous anisotropic universe is modified by Loop Quantum Cosmology and, consequently, it has generically a big bounce in the past instead of a big-bang singularity. This modified dynamics can be well described by effective equations of motion. We generalise these effective equations of motion empirically to (d + 1) dimensions. The generalised equations involve two functions and may be considered as a class of LQC -- inspired models for (d + 1) dimensional early universe cosmology. As a special case, one can now obtain a universe which has neither a big bang singularity nor a big bounce but approaches asymptotically a `Hagedorn like' phase in the past where its density and volume remain constant. In a few special cases, we also obtain explicit solutions.

  18. A class of LQC-inspired models for homogeneous, anisotropic cosmology in higher dimensional early universe

    Science.gov (United States)

    Rama, S. Kalyana

    2016-12-01

    The dynamics of a (3 + 1) dimensional homogeneous anisotropic universe is modified by loop quantum cosmology and, consequently, it has generically a big bounce in the past instead of a big-bang singularity. This modified dynamics can be well described by effective equations of motion. We generalise these effective equations of motion empirically to (d + 1) dimensions. The generalised equations involve two functions and may be considered as a class of LQC-inspired models for (d + 1) dimensional early universe cosmology. As a special case, one can now obtain a universe which has neither a big bang singularity nor a big bounce but approaches asymptotically a `Hagedorn like' phase in the past where its density and volume remain constant. In a few special cases, we also obtain explicit solutions.

  19. 大爆炸(Big Bang)和暗能量(dark energy)%Big Bang and Dark Energy

    Institute of Scientific and Technical Information of China (English)

    李竞

    2003-01-01

    @@ 20世纪20年代之前,科学家运用经典力学考察宇宙的大尺度结构,得出的结论是:我们的宇宙无论在时间上,还是在空间上,都是无限的,永恒的,无始无终的.这个无限时空的宇宙观广为世人赞赏和认同.

  20. Putting the five-factor model into context: evidence linking big five traits to narrative identity.

    Science.gov (United States)

    Raggatt, Peter

    2006-10-01

    The study examined relationships between the Big Five personality traits and thematic content extracted from self-reports of life history data. One hundred and five "mature age" university students (M=30.1 years) completed the NEO PI-R trait measure, and the Personality Web Protocol. The protocol examines constituents of identity by asking participants to describe 24 key "attachments" from their life histories (significant events, people, places, objects, and possessions). Participants sorted these attachments into clusters and provided a self-descriptive label for each cluster (e.g., "adventurous self"). It was predicted that the thematic content of these cluster labels would be systematically related to Big Five trait scores (e.g., that labels referring to strength or positive emotions would be linked to Extraversion). The hypothesized links were obtained for each of the Big Five trait domains except Conscientiousness. Results are discussed with a view to broadening our understanding of the Five-Factor Model in relation to units of personality other than traits.