Does Dark Energy Really Exist?
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Probing the Dark Flow Signal in WMAP 9Yr and PLANCK CMB Maps
Probing the Dark Flow signal in WMAP 9yr and PLANCK CMB Maps. Fernando Atrio-Barandela. Departamento de F´ısica Fundamental. Universidad de Salamanca. eml: [email protected] In collaboration with: H. Ebeling, D. Fixsen, A. Kashlinsky, D. Kocevski. Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 1 Summary. Introduction: The CMB dipole. Measuring Peculiar Velocities. Results with WMAP. Results with PLANCK (Planck Collaboration). Results with PLANCK (Our Analysis). Cosmological Implications and Conclusions. Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 2 Introduction: The CMB dipole. Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 3 The Cosmic Microwave Background. Monopole T=2.73K Dipole T=3mK Octupole O=33 K Planck Nominal Map at 353GHz Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 4 The CMB dipole. If density perturbations are adiabatic, generated during inflation, then the low order • multipoles verify: ℓ(ℓ + 1)C = const 2C = 12C = 12 1000(µK)2 D 70µ 1mK ℓ ⇒ 1 3 ∗ ⇒ ∼ ≪ Then, the dipole CAN NOT BE PRIMORDIAL. It is a Doppler effect due to the local motion of the Local Group with velocity 600km/s in the direction of l = 2700, b = 300. ∼ Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 5 The convergence of the CMB dipole. COMA VIRGO CENTAURUS HYDRA PERSEUS (Left) CMB dipole measured by COBE. (Right) Large Scale Structure and gas distribution in the Local Universe. What are the scales that contribute to the 600km/s peculiar velocity of the LG? ∼ Ibericos 2015 Aranjuez, March 30th - April 1st, 2015. 6 Bulk Flows. The zero order moment of the velocity field is the mean peculiar velocity of a sphere of radius R or bulk flow 1 V 2(R) = P (k)W 2(kR)dk P (k) = δ(k) 2. -
The Triple-Quasar Is an Optical Image of Milkyway, Andromeda and Triangulum Galaxies – Implies Expansion in the Direction of Dark Flow
The Triple-quasar is an optical image of Milkyway, Andromeda and Triangulum galaxies – implies expansion in the direction of Dark Flow Jose P Koshy [email protected] Abstract: Based on the concept that light follows a circular path of radius 2.5 billion light-years, here I show that the triple-quasar LBQS 1429-008 is the 10.5 billion years old image of 'Milkyway, Andromeda and Triangulum' galaxies. From this, the position of our galaxy at two different times can be ascertained, and the direction of expansion of the universe can be estimated. The 'surprise finding' is that the direction thus obtained is in agreement with the direction of so- called 'Dark flow', implying the possibility that the expansion is due to actual motion of bodies, and hence LCDM model is wrong. 1. Introduction: The standard cosmological model (LCDM) visualizes metric expansion of the universe. In such a model, the motion of galaxy clusters with respect to the cosmic microwave background should be randomly distributed in all directions. However, using WMAP data, Alexander Kashlinsky1 et al have found evidence for a possible non-random component in the motion of galaxy clusters; this is referred to as 'dark flow'. This implies the possibility that expansion is due to actual 'physical motion' of bodies. An alternate model, explained in my previous papers, visualizes expansion as a consequence of 'actual motion' of galaxy-clusters. Also, the model visualizes that light follows a 'circular path', and so the returning rays can create past images of bodies that have moved out. So, based on that model, it becomes possible to ascertain 'the direction' in which the universe in our region expands. -
Astrophysics Notre Dame’S Partnership in the Large Binocular Telescope
NOTRE DAME ASTROPHYSICS NOTRE DAME’S PARTNERSHIP IN THE LARGE BINOCULAR TELESCOPE The Large Binocular Telescope (LBT) stands on carbon and oxygen are created, and the LBT will Mt. Graham in Arizona, at 10,700 feet above sea support our quest for understanding. level, and next to the 1.8-m Vatican Advanced Technology Telescope. The unique facility is Telescopes not only look at distant objects, actually two 8.4-m telescopes that act in tandem but also act as time machines. Because light to produce images unlike any seen before. The may travel for billions of years before being LBT has the equivalent collecting power of a captured by the LBT’s mirrors, the images 12-m and the resolution of a 22-m telescope, far reveal the Universe as it was long ago. One of better than any other telescope today. It is the the big mysteries uncovered by the Hubble forerunner of the next generation of ultra-large Space Telescope program is the existence of telescopes. fully formed galaxies in the early universe, much earlier than physicists predicted. Their formation The LBT has extraordinary capabilities. will be a key research program for the LBT and Its design allows it to directly observe distant Origins Institute faculty Dinshaw Balsara and stars systems and to actually see planets in the Christopher Howk, who aim to understand the systems. Its ability to measure very precise atomic dynamics that govern the formation of galaxies spectra even enables researchers to determine the and with them the beginnings of life. chemical makeup of the planets’ atmospheres. -
What's in This Issue?
A JPL Image of surface of Mars, and JPL Ingenuity Helicioptor illustration. July 11th at 4:00 PM, a family barbeque at HRPO!!! This is in lieu of our regular monthly meeting.) (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory) This is a pot-luck. Club will provide briskett and beverages, others will contribute as the spirit moves. What's In This Issue? President’s Message Member Meeting Minutes Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night SubReddit and Discord BRAS Member Astrophotos ARTICLE: Astrophotography with your Smart Phone Observing Notes: Canes Venatici – The Hunting Dogs Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society BRAS YouTube Channel Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 23 July 2021 President’s Message Hey everybody, happy fourth of July. I hope ya’ll’ve remembered your favorite coping mechanism for dealing with the long hot summers we have down here in the bayou state, or, at the very least, are making peace with the short nights that keep us from enjoying both a good night’s sleep and a productive observing/imaging session (as if we ever could get a long enough break from the rain for that to happen anyway). At any rate, we figured now would be as good a time as any to get the gang back together for a good old fashioned potluck style barbecue: to that end, we’ve moved the July meeting to the Sunday, 11 July at 4PM at HRPO. -
The Triggering of Starbursts in Low-Mass Galaxies
Mon. Not. R. Astron. Soc. 000, 000{000 (0000) Printed 28 September 2018 (MN LATEX style file v2.2) The triggering of starbursts in low-mass galaxies Federico Lelli1;2 ?, Marc Verheijen2, Filippo Fraternali3;1 1Department of Astronomy, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106, USA 2Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV, Groningen, The Netherlands 3Department of Physics and Astronomy, University of Bologna, via Berti Pichat 6/2, 40127, Bologna, Italy ABSTRACT Strong bursts of star formation in galaxies may be triggered either by internal or ex- ternal mechanisms. We study the distribution and kinematics of the H I gas in the outer regions of 18 nearby starburst dwarf galaxies, that have accurate star-formation histories from HST observations of resolved stellar populations. We find that star- burst dwarfs show a variety of H I morphologies, ranging from heavily disturbed H I distributions with major asymmetries, long filaments, and/or H I-stellar offsets, to lop- sided H I distributions with minor asymmetries. We quantify the outer H I asymmetry for both our sample and a control sample of typical dwarf irregulars. Starburst dwarfs have more asymmetric outer H I morphologies than typical irregulars, suggesting that some external mechanism triggered the starburst. Moreover, galaxies hosting an old burst (&100 Myr) have more symmetric H I morphologies than galaxies hosting a young one (.100 Myr), indicating that the former ones probably had enough time to regularize their outer H I distribution since the onset of the burst. We also investigate the nearby environment of these starburst dwarfs and find that most of them (∼80%) have at least one potential perturber at a projected distance .200 kpc. -
Arxiv:1807.06205V1 [Astro-Ph.CO] 17 Jul 2018 1 Introduction2 3 the ΛCDM Model 18 2 the Sky According to Planck 3 3.1 Assumptions Underlying ΛCDM
Astronomy & Astrophysics manuscript no. ms c ESO 2018 July 18, 2018 Planck 2018 results. I. Overview, and the cosmological legacy of Planck Planck Collaboration: Y. Akrami59;61, F. Arroja63, M. Ashdown69;5, J. Aumont99, C. Baccigalupi81, M. Ballardini22;42, A. J. Banday99;8, R. B. Barreiro64, N. Bartolo31;65, S. Basak88, R. Battye67, K. Benabed57;97, J.-P. Bernard99;8, M. Bersanelli34;46, P. Bielewicz80;8;81, J. J. Bock66;10, 7 12;95 57;92 71;56;57 2;6 45;32;48 42 85 J. R. Bond , J. Borrill , F. R. Bouchet ∗, F. Boulanger , M. Bucher , C. Burigana , R. C. Butler , E. Calabrese , J.-F. Cardoso57, J. Carron24, B. Casaponsa64, A. Challinor60;69;11, H. C. Chiang26;6, L. P. L. Colombo34, C. Combet73, D. Contreras21, B. P. Crill66;10, F. Cuttaia42, P. de Bernardis33, G. de Zotti43;81, J. Delabrouille2, J.-M. Delouis57;97, F.-X. Desert´ 98, E. Di Valentino67, C. Dickinson67, J. M. Diego64, S. Donzelli46;34, O. Dore´66;10, M. Douspis56, A. Ducout57;54, X. Dupac37, G. Efstathiou69;60, F. Elsner77, T. A. Enßlin77, H. K. Eriksen61, E. Falgarone70, Y. Fantaye3;20, J. Fergusson11, R. Fernandez-Cobos64, F. Finelli42;48, F. Forastieri32;49, M. Frailis44, E. Franceschi42, A. Frolov90, S. Galeotta44, S. Galli68, K. Ganga2, R. T. Genova-Santos´ 62;15, M. Gerbino96, T. Ghosh84;9, J. Gonzalez-Nuevo´ 16, K. M. Gorski´ 66;101, S. Gratton69;60, A. Gruppuso42;48, J. E. Gudmundsson96;26, J. Hamann89, W. Handley69;5, F. K. Hansen61, G. Helou10, D. Herranz64, E. Hivon57;97, Z. Huang86, A. -
Proof for a Rotational Double Torus Universe
Proof For A Rotational Double Torus Universe. Author: Dan Visser, Almere, the Netherlands. Date: January 19 2014 (version-1); April 28 2014 (version-2) Abstract. The Universe rotates. We live in a Double Torus Universe. A dark matter torus rotates in a larger time torus of refined time smaller than the Planck-time. The Planck-satellite showed a more detailed picture of the CMB related to Big Bang cosmology. However, I have put that in perspective of a new set of equations that belong to the framework of the Double Torus Theory. That shows my proof for a rotational dark matter Flow by warm and cold areas in the CMB. I also explain why the accelerated space-expansion in the Big Bang cosmology is an illusion. Introduction. I refer to an article that was published in Physics World. In that article Professor Peter Coles of the University of Sussex, UK, explained the Planck perspectives [1]. I wrote him an email explaining I found proof for a rotational Double Torus Universe, instead of a Big Bang. I also found the argument why an accelerated space-time is observed and why this is an illusion from the perspective of the Double Torus Theory. I have printed a copy of that email, as follows: Dear Peter Coles, I read your article in Physics World about ‘Planck Perspectives’. Very well. But that is what I needed to make a statement the Big Bang cannot be maintained as the current cosmological model. I have gathered proof for that. I published my articles in the Vixra- archive (www.vixra.org/author/dan_visser). -
Mysterious Cosmic 'Dark Flow' Tracked Deeper Into Universe (W/ Video) 10 March 2010
Mysterious Cosmic 'Dark Flow' Tracked Deeper into Universe (w/ Video) 10 March 2010 but right now our data cannot state as strongly as we'd like whether the clusters are coming or going," Kashlinsky said. The dark flow is controversial because the distribution of matter in the observed universe cannot account for it. Its existence suggests that some structure beyond the visible universe -- outside our "horizon" -- is pulling on matter in our vicinity. Cosmologists regard the microwave background -- The colored dots are clusters within one of four distance a flash of light emitted 380,000 years after the ranges, with redder colors indicating greater distance. universe formed -- as the ultimate cosmic reference Colored ellipses show the direction of bulk motion for the frame. Relative to it, all large-scale motion should clusters of the corresponding color. Images of representative galaxy clusters in each distance slice are show no preferred direction. also shown. Credit: NASA/Goddard/A. Kashlinsky, et al. The hot X-ray-emitting gas within a galaxy cluster scatters photons from the cosmic microwave background (CMB). Because galaxy clusters don't (PhysOrg.com) -- Distant galaxy clusters precisely follow the expansion of space, the mysteriously stream at a million miles per hour wavelengths of scattered photons change in a way along a path roughly centered on the southern that reflects each cluster's individual motion. constellations Centaurus and Hydra. A new study led by Alexander Kashlinsky at NASA's Goddard This results in a minute shift of the microwave Space Flight Center in Greenbelt, Md., tracks this background's temperature in the cluster's direction. -
On the Evolution of Large-Scale Structure in a Cosmic Void
On the Evolution of Large-Scale Structure in a Cosmic Void Town Sean Philip February Cape of Thesis Presented for the Degree of UniversityDoctor of Philosophy in the Department of Mathematics and Applied Mathematics University of Cape Town February 2014 Supervised by Assoc. Prof. Chris A. Clarkson & Prof. George F. R. Ellis The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. The thesis is to be used for private study or non- commercial research purposes only. Cape Published by the University ofof Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University ii Contents Declaration vii Abstract ix Acknowledgements xi Conventions and Acronyms xiii 1 The Standard Model of Cosmology 1 1.1 Introduction 1 1.1.1 Historical Overview 1 1.1.2 The Copernican Principle 5 1.2 Theoretical Foundations 10 1.2.1 General Relativity 10 1.2.2 Background Dynamics 10 1.2.3 Redshift, Cosmic Age and distances 13 1.2.4 Growth of Large-Scale Structure 16 1.3 Observational Constraints 23 1.3.1 Overview 23 1.3.2 A Closer Look at the BAO 27 iii 1.4 Challenges, and Steps Beyond 31 2 Lemaˆıtre-Tolman-Bondi Cosmology 35 2.1 Motivation and Review 35 2.2 Background Dynamics 37 2.2.1 Metric and field equations 37 2.2.2 Determining the solution 40 2.2.3 Connecting to observables 41 2.3 Linear Perturbation Theory in LTB 46 2.3.1 Introduction 46 2.3.2 Defining the perturbations 47 2.3.3 Einstein equations 57 2.3.4 The homogeneous -
Arxiv:Astro-Ph/0401239V1 13 Jan 2004
Paper status: Accepted to the ApJ Missing Massive Stars in Starbursts: Stellar Temperature Diagnostics and the IMF J. R. Rigby and G. H. Rieke Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 [email protected], [email protected] ABSTRACT Determining the properties of starbursts requires spectral diagnostics of their ultraviolet ra- diation fields, to test whether very massive stars are present. We test several such diagnostics, using new models of line ratio behavior combining Cloudy, Starburst99 and up-to-date spectral atlases (Pauldrach et al. 2001; Hillier & Miller 1998). For six galaxies we obtain new measure- ments of Hei 1.7 µm/Br10, a difficult to measure but physically simple (and therefore reliable) diagnostic. We obtain new measurements of Hei 2.06 µm/Brγ in five galaxies. We find that Hei 2.06 µm/Brγ and [Oiii]/Hβ are generally unreliable diagnostics in starbursts. The het- eronuclear and homonuclear mid–infrared line ratios (notably [Neiii] 15.6 µm / [Neii] 12.8 µm) consistently agree with each other and with Hei 1.7 µm/Br10; this argues that the mid–infrared line ratios are reliable diagnostics of spectral hardness. In a sample of 27 starbursts, [Neiii]/[Neii] is significantly lower than model predictions for a Salpeter IMF extending to 100 M⊙. Plausi- ble model alterations strengthen this conclusion. By contrast, the low–mass and low–metallicity galaxies II Zw 40 and NGC 5253 show relatively high neon line ratios, compatible with a Salpeter slope extending to at least ∼ 40–60 M⊙. One solution for the low neon line ratios in the high– metallicity starbursts would be that they are deficient in & 40 M⊙ stars compared to a Salpeter IMF. -
Arxiv:1701.08720V1 [Astro-Ph.CO]
Foundations of Physics manuscript No. (will be inserted by the editor) Tests and problems of the standard model in Cosmology Mart´ın L´opez-Corredoira Received: xxxx / Accepted: xxxx Abstract The main foundations of the standard ΛCDM model of cosmology are that: 1) The redshifts of the galaxies are due to the expansion of the Uni- verse plus peculiar motions; 2) The cosmic microwave background radiation and its anisotropies derive from the high energy primordial Universe when matter and radiation became decoupled; 3) The abundance pattern of the light elements is explained in terms of primordial nucleosynthesis; and 4) The formation and evolution of galaxies can be explained only in terms of gravi- tation within a inflation+dark matter+dark energy scenario. Numerous tests have been carried out on these ideas and, although the standard model works pretty well in fitting many observations, there are also many data that present apparent caveats to be understood with it. In this paper, I offer a review of these tests and problems, as well as some examples of alternative models. Keywords Cosmology · Observational cosmology · Origin, formation, and abundances of the elements · dark matter · dark energy · superclusters and large-scale structure of the Universe PACS 98.80.-k · 98.80.E · 98.80.Ft · 95.35.+d · 95.36.+x · 98.65.Dx Mathematics Subject Classification (2010) 85A40 · 85-03 1 Introduction There is a dearth of discussion about possible wrong statements in the foun- dations of standard cosmology (the “Big Bang” hypothesis in the present-day Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain Departamento de Astrof´ısica, Universidad de La Laguna, E-38206 La Laguna, Tenerife, Spain arXiv:1701.08720v1 [astro-ph.CO] 30 Jan 2017 Tel.: +34-922-605264 Fax: +34-922-605210 E-mail: [email protected] 2 Mart´ın L´opez-Corredoira version of ΛCDM, i.e. -
Arxiv:1310.7574V2 [Astro-Ph.CO] 13 Mar 2015 Ground Radiation—Large-Scale Structure of Universe
A Simple Gravitational Lens Model For Cosmic Voids Bin Chen1;2, Ronald Kantowski1, Xinyu Dai1 ABSTRACT We present a simple gravitational lens model to illustrate the ease of using the embedded lensing theory when studying cosmic voids. It confirms the previously used repulsive lensing models for deep voids. We start by estimating magnitude fluctuations and weak lensing shears of background sources lensed by large voids. We find that sources behind large (∼90 Mpc) and deep voids (density contrast about −0:9) can be magnified or demagnified with magnitude fluctuations of up to ∼0:05 mag and that the weak-lensing shear can be up to the ∼10−2 level in the outer regions of large voids. Smaller or shallower voids produce proportionally smaller effects. We investigate the \wiggling" of the primary cosmic microwave background (CMB) temperature anisotropies caused by intervening cosmic voids. The void-wiggling of primary CMB temperature gradients is of the opposite sign to that caused by galaxy clusters. Only extremely large and deep voids can produce wiggling amplitudes similar to galaxy clusters, ∼15 µK by a large void of radius ∼4◦ and central density contrast −0:9 at redshift 0.5 assuming a CMB background gradient of ∼10 µK arcmin−1. The dipole signal is spread over the entire void area, and not concentrated at the lens' center as it is for clusters. Finally we use our model to simulate CMB sky maps lensed by large cosmic voids. Our embedded theory can easily be applied to more complicated void models and used to study gravitational lensing of the CMB, to probe dark-matter profiles, to reduce the lensing-induced systematics in supernova Hubble diagrams, as well as study the integrated Sachs-Wolfe effect.