Euclid Imaging Consortium Science Book

Total Page:16

File Type:pdf, Size:1020Kb

Euclid Imaging Consortium Science Book EIC Science Book by the Euclid Imaging Consortium EDITED BY: Alexandre R´efr´egier and Adam Amara Thomas Kitching Ana¨ıs Rassat Roberto Scaramella Jochen Weller 1st January 2010 Euclid Imaging Consortium Euclid Imaging Consortium Members PI: Alexandre Refregier (CEA Saclay) Co-PIs: Ralf Bender (MPE Germany), Mark Cropper (MSSL, UK), Roberto Scaramella (INAF- Oss. Roma, Italy), Simon Lilly (ETH Zurich, Switzerland), Nabila Aghanim (IAS Orsay, France), Francisco Castander (IEEC Barcelona, Spain), Jason Rhodes (JPL, USA) Study Manager: Jean-Louis Augueres (CEA Saclay) System engineer: Jerome Amiaux (CEA Saclay) Instrument scientists: Mario Schweitzer (MPE), Mark Cropper (MSSL) Olivier Boulade (CEA Saclay), Adam Amara (ETH Zurich), Jeff Booth (JPL), Anna Maria di Giorgio (INAF-IFSI) Co-Investigators: France: Marian Douspis (IAS Orsay), Yannick Mellier (IAP Paris), Olivier Boulade (CEA Saclay), Germany: Peter Schneider (U. Bonn), Oliver Krause (MPIA Heidelberg), Frank Eisenhauer (MPE Garching), Italy: Lauro Moscardini (U. Bologna), Luca Amendola (INAF-Oss. Roma and University of Heidelberg), Fabio Pasian (INAF-OATS), Spain: Ramon Miquel (IFAE Barcelona), Eusebio Sanchez (CIEMAT Madrid), Switzerland: George Meylan (EPFL-UniGE), Marcella Carollo (ETH Zurich), Francois Widi (EPFL-UniGE), UK: John Peacock (IfA Edinburgh), Sarah Bridle (UCL, London), Ian Bryson (IfA Edinburgh), USA: Jeff Booth (JPL), Steven Kahn (Stanford U.) Science working group coordinators: Weak Lensing: Adam Amara (ETH Zurich), Andy Taylor (IfA Edinburgh) Clusters/CMB: Jochen Weller (U. Munich/MPE), Nabila Aghanim (IAS Orsay) BAO (photometric): Francisco Castander (IEEC Barcelona), Anais Rassat (CEA Saclay) Supernovae: Isobel Hook (Oxford, and Obs. Rome), Massimo Della Valle (Oss. Capodi- monte/ICRA) Theory: Luca Amendola (INAF-Oss. Roma), Martin Kunz (U. Sussex/U. Geneva) Strong Lensing: Matthias Bartelmann (U. Heidelberg), Leonidas Moustakas (JPL) Galaxy Evolution: Marcella Carollo (ETH Zurich), Hans-Walter Rix (MPIA) Galactic studies and planets: Eva Grebel (U. Heidelberg), Jean-Philippe Beaulieu (IAP Paris), Photometric Redshifts: Ofer Lahav (UCL), Adriano Fontana (INAF Oss. Roma) Image Simulations: Jason Rodes (JPL), Lauro Moscardini (U. Bologna) Communication: Marian Douspis (IAS Orsay) Science: France: Karim Benabed (IAP), Emmanuel Bertin (IAP), Pascal Bord´e(IAS Orsay), Frederic Bournaud (CEA Saclay), Marian Douspis (IAS Orsay), Herve Dole (IAS Orsay), Raphael Gavazzi (IAP), Guilaine Lagache (IAS Orsay), M. Langer (IAS Orsay), Henry McCracken (IAP), Christophe, Magneville (CEA Saclay), M. Ollivier (IAS Orsay), Nathalie Palanque-Delabrouille (CEA Saclay), Stephane Paulin-Henriksson (CEA Saclay), Sandrine Pires (CEA Saclay), Jean-Luc Starck (CEA Saclay), Romain Teyssier (CEA Saclay/U. Zurich) Germany: Wolfgang Brandner (MPIA), Hans B¨ohringer(MPE), Frank Eisenhauer (MPE), Natascha Foerster-Schreiber (MPE), Bertrand Goldman (MPIA), Oliver Krause (MPIA), Peter Melchior (ITA - Heidelberg), Steffi Phleps (MPE), Roberto Saglia (MPE), Stella Seitz (MPE), Peter Schneider (Univ. Bonn), Benjamin Joachimi (Univ. Bonn), Joachim Wambsgans (Univ. Heidelberg), David Wilman (MPE) Italy: Vicenzo Antonuccio (INAF-Oss. Catania), Carlo Baccigalupi (SISSA), Fabio Bellagamba (U. di Bologna), Silvio Bonometto (U. Milano Bicocca), Andrea Grazian (INAF- Oss. Roma), 4 Marco Lombardi (U. di Milano), Roberto Mainini (INAF Oss. Roma), Filippo Mannucci (INAF - IRA), Roberto Maoli (U. Roma La Sapienza), Sabino Matarrese (U. di Padova), Alessandro Melchiorri (U. Roma La Sapienza), Massimo Meneghetti (INAF- Oss. Bologna), Julian Merten (INAF Oss. Bologna), Lauro Moscardini (U. di Bologna), Claudia Quercellini (U. Roma Tor Vergata), Mario Radovich (INAF Oss. Capodimonte), Anna Romano (U. Roma La Sapienza), Roberto Scaramella (INAF Oss. Roma), Andrea Zacchei (INAF - Oss. Trieste) Spain: Ricard Casas (IEEC Barcelona), Martin Crocce (IEEC Barcelona), Pablo Fosalba (IEEC Barcelona), Enrique Gaztanaga (IEEC Barcelona), Ignacio Sevilla (CIEMAT Madrid), Eusebio Sanchez (CIEMAT Madrid), Juan Garcia-Bellido (UAM Madrid) Switzerland: Rongmon Bordoloi (ETH Zurich), Julien Carron (ETH Zurich), Frederic Courbin (EPFL Lausanne), Stephane Paltani (ISDC/U. Geneva), Justin Read (U. Zurich/U. Leicester), Robert Smith (U. Zurich) UK: Filipe Abdalla (UCL), Manda Banerji (UCL), David Bacon (U. Portsmouth), Kirk Donnacha (UCL), Ignacio Ferreras (MSSL-UCL), Gert Hutsi (UCL), Alan Heavens (IfA Edinburgh), Tom Kitching (IfA Edinburgh), Lindsay King (IoA Cambridge), Ofer Lahav (UCL), Katarina Markovic (UCL/Ludwigs-Maximilians U.), Richard Massey (IfA Edinburgh), Michael Schneider (U. Durham), Fabrizio Sidoli (UCL), Jiayu Tang (UCL/IPMU), Shaun Thomas (UCL), Lisa Voigt (UCL) USA: Joel Berge (JPL), Benjamin Dobke (JPL), Richard Ellis (Caltech), David Johnston (Northwest. U.), Michael Seiffert (JPL), Ali Vanderveld (JPL) Other: Eduardo Cypriano (U. Sao Paulo), Hakon Dahle (U. Oslo), Konrad Kuijken (Leiden) Instrument: France: Christophe Cara (CEA Saclay), Sandrine Cazaux (CEA Saclay), Arnaud Claret (CEA Saclay), Philippe Daniel-Thomas (CEA Saclay), Eric Doumayrou (CEA Saclay), Cydalise Dusmesnil (IAS Orsay), Jean-Jacques Fourmond (IAS Orsay), Jean-Claude Leclech (IAS Orsay), G. Morinaud (IAS Orsay), Samuel Ronayette (CEA Saclay), Zihong Sun (CEA Saclay), Tristan VanDenBerghe (IAS Orsay) Germany: Reiner Hofmann (MPE), Rory Holmes (MPIA), Reinhard Katterloher (MPE), Oliver Krause (MPIA) Italy: Marco Frailis (INAF Oss. Trieste), Pasquale Cerulli Irelli (INAF IFSI), Stefano Gallozzi (INAF Oss. Roma), Michele Maris (INAF Oss. Trieste), Renato Orfei (INAF IFSI), Fabio Pasian (INAF Oss. Trieste), Andrea Zacchei (INAF - Oss. Trieste) Spain: Laia Cardiel (IFAE Barcelona), Francesc Madrid (IEEC Barcelona), Santiago Serrano (IEEC Barcelona) Switzerland: Adrian Glauser (ETH Zurich), Francois Wildi (ISDC/U. Geneva) UK: Eli Atad-Ettedgui (UK-ATC), Ian Bryson (UK-ATC), Richard Cole (MSSL), Jason Gow (Open U), Phil Guttridge (MSSL) , Andrew Holland (Open U), Neil Murray (Open U), Kerrin Rees (MSSL), Phil Thomas (MSSL), Dave Walton (MSSL) USA: Parker Fagrelius (JPL), Kirk Gilmore (Stanford), Steven Kahn (Stanford), Andrew Ras- mussen (Stanford), Suresh Seshadri (JPL), Roger Smith (Caltech), Harry Teplitz (IPAC/Caltech) Acknowledgements We thank the national agencies and institutes in the EIC member countries for their support of the consortium during the assessment phase. We are particularly grateful to CNES, CEA, CNRS, CNAP in France, DLR and the Max Planck Society in Germany, STFC in the UK, ASI (contract “Euclid-DUNE” No. I/064/08/0) in Italy, ETH Zurich, EPF Lausanne and U. Geneva in Switzerland, the Spanish Ministerio de Educacion y Ciencia (grant ESP2007-29984-E) and the Spanish Ministerio de Ciencia e Innovacion (grant AYA2008-03347-E/ESP) in Spain, and the Jet Propulsion Laboratory, run under a contract for NASA by the California Institute of Technology in the US. We also thank ESA for their coordination of the Euclid Assessment phase, and the members of the Euclid Science Study team and of the ENIS consortium for scientific interactions. 5 Contents List of Authors 3 Acknowledgements 5 Table of Contents 6 I INTRODUCTION 12 1 Overview 13 1.1 Introduction ....................................... 13 1.2 The Euclid Mission ................................... 14 1.3 The Euclid Imaging Instrument and Surveys ..................... 15 1.4 Primary Science .................................... 16 1.5 Legacy Science ..................................... 17 1.6 Simulations ....................................... 18 1.7 Data handling ...................................... 18 2 Publications 20 2.1 Collaboration Papers .................................. 20 2.2 Science working groups and related papers ...................... 20 II THEORY 23 3 Fundamental Cosmology with Euclid: A Theoretical Perspective 24 3.1 Introduction ....................................... 24 3.2 Phenomenology vs fundamental theory of the dark energy ............. 26 3.3 Beyond the background ................................ 26 3.4 Extracting the potentials with Euclid ......................... 29 3.5 Dark Matter ...................................... 30 3.6 Initial Conditions .................................... 31 3.7 Synergy of Euclid with LHC, EELT and Gaia .................... 32 6 Contents 7 3.8 Conclusions ....................................... 33 III WEAK GRAVITATIONAL LENSING 36 4 EIC Weak Lensing 37 4.1 Introduction ....................................... 37 4.2 Basics of Weak Lensing ................................ 38 4.3 Developing the Science Case .............................. 39 4.3.1 Summary of the Predictions .......................... 39 4.4 Code comparison .................................... 40 4.5 Mitigation of Systematic effects ............................ 41 4.5.1 Setting Systematic Limits ........................... 42 4.5.2 Shape Measurement .............................. 42 4.6 Summary of Top Level Requirements ......................... 44 5 Weak Lensing Survey Optimisation for Dark Energy Measurement 48 5.1 Introduction ....................................... 48 5.2 Optimising the survey geometry ............................ 48 5.3 Optimising constraints on cosmological parameters ................. 50 5.3.1 Towards a more precise description of dark energy ............. 52 5.4 Conclusion ....................................... 52 6 Modified Gravity with Lensing 55 6.1 Introduction ....................................... 55 6.2 Distinguishing between
Recommended publications
  • NUSTAR REVEALS an INTRINSICALLY X-RAY WEAK BROAD ABSORPTION LINE QUASAR in the ULTRALUMINOUS INFRARED GALAXY MARKARIAN 231 Stacy H
    Accepted, 18 February, 2014 Preprint typeset using LATEX style emulateapj v. 11/10/09 NUSTAR REVEALS AN INTRINSICALLY X-RAY WEAK BROAD ABSORPTION LINE QUASAR IN THE ULTRALUMINOUS INFRARED GALAXY MARKARIAN 231 Stacy H. Teng1, 22, W.N. Brandt2, F.A. Harrison3,B.Luo2, D.M. Alexander4,F.E.Bauer5, 6, S.E. Boggs7,F.E. Christensen8,A.,Comastri9, W.W. Craig10, 7,A.C.Fabian11, D. Farrah12,F.Fiore13, P. Gandhi4,B.W. Grefenstette3,C.J.Hailey14,R.C.Hickox15, K.K. Madsen3,A.F.Ptak16, J.R. Rigby1, G. Risaliti17, 18, C. Saez5, D. Stern19, S. Veilleux20, 21, D.J. Walton3,D.R.Wik16, 22, & W.W. Zhang16 (Received; Accepted) Accepted, 18 February, 2014 ABSTRACT We present high-energy (3–30 keV) NuSTAR observations of the nearest quasar, the ultralumi- nous infrared galaxy (ULIRG) Markarian 231 (Mrk 231), supplemented with new and simultaneous low-energy (0.5–8 keV) data from Chandra. The source was detected, though at much fainter levels than previously reported, likely due to contamination in the large apertures of previous non-focusing hard X-ray telescopes. The full band (0.5–30 keV) X-ray spectrum suggests the active galactic nu- ∼ . +0.3 × 23 −2 cleus (AGN) in Mrk 231 is absorbed by a patchy and Compton-thin (NH 1 2−0.3 10 cm ) 43 −1 column. The intrinsic X-ray luminosity (L0.5−30 keV ∼ 1.0 × 10 erg s ) is extremely weak relative to the bolometric luminosity where the 2–10 keV to bolometric luminosity ratio is ∼0.03% compared to the typical values of 2–15%.
    [Show full text]
  • Explosion Shutting Down a Galactic Party: Physicists
    "Long before it's in the papers" R E T URN T O T H E W O R L D SC I E N C E H O M E PA G E Explosion shutting down a galactic party: physicists Feb. 23, 2011 Courtesy of the Gemini Observatory and World Science staff An immense black hole in a galaxy far, far away seems to be causing an explosion that will change that galaxy forever, scientists say. Blasts of its type, never reported in detail before, will snuff out a galactic party, they predict: like a suddenly enraged father who at a holiday feast yanks the tablecloth high into the air, the black hole is in a sense tossing its own meals out of the galaxy. And everyone else’s, too, because some of this same material is expected to have been nourishing a flurry of new star formation elsewhere in the galaxy, which will now stop. Artist’s conceptual of the environment around the supermas- sive black hole at the center of Mrk 231. The broad outflow seen in the Gemini data is shown as the fan-shaped wedge at the top of the accretion disk around the black hole. This side- view is not what is seen from the Earth where we see it ‘look- ing down the throat’ of the outflow. A similar outflow is proba- bly present under the disk as well and is hinted at in this illus- tration. The total amount of material entrained in the broad flow is at least 400 times the mass of the Sun per year.
    [Show full text]
  • Herschel-PACS Spectroscopic Diagnostics of Local Ulirgs
    A&A 518, L41 (2010) Astronomy DOI: 10.1051/0004-6361/201014676 & c ESO 2010 Astrophysics Herschel: the first science highlights Special feature Letter to the Editor Herschel-PACS spectroscopic diagnostics of local ULIRGs: Conditions and kinematics in Markarian 231 J. Fischer1,,E.Sturm2, E. González-Alfonso3 , J. Graciá-Carpio2, S. Hailey-Dunsheath2 ,A.Poglitsch2, A. Contursi2,D.Lutz2, R. Genzel2,A.Sternberg4,A.Verma5, and L. Tacconi2 1 Naval Research Laboratory, Remote Sensing Division, 4555 Overlook Ave SW, Washington, DC 20375, USA e-mail: [email protected] 2 Max-Planck-Institut für extraterrestrische Physik (MPE), Postfach 1312, 85741 Garching, Germany 3 Universidad de Alcala de Henares, Departamento de Fisica, Campus Universitario, Spain 4 Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel 5 University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK Received 31 March 2010 / Accepted 5 May 2010 ABSTRACT In this first paper on the results of our Herschel PACS survey of local ultra luminous infrared galaxies (ULIRGs), as part of our SHINING survey of local galaxies, we present far-infrared spectroscopy of Mrk 231, the most luminous of the local ULIRGs, and a type 1 broad absorption line AGN. For the first time in a ULIRG, all observed far-infrared fine-structure lines in the PACS range were detected and all were found to be deficient relative to the far infrared luminosity by 1–2 orders of magnitude compared with lower luminosity galaxies. The deficits are similar to those for the mid-infrared lines, with the most deficient lines showing high ionization potentials.
    [Show full text]
  • A Multimessenger View of Galaxies and Quasars from Now to Mid-Century M
    A multimessenger view of galaxies and quasars from now to mid-century M. D’Onofrio 1;∗, P. Marziani 2;∗ 1 Department of Physics & Astronomy, University of Padova, Padova, Italia 2 National Institute for Astrophysics (INAF), Padua Astronomical Observatory, Italy Correspondence*: Mauro D’Onofrio [email protected] ABSTRACT In the next 30 years, a new generation of space and ground-based telescopes will permit to obtain multi-frequency observations of faint sources and, for the first time in human history, to achieve a deep, almost synoptical monitoring of the whole sky. Gravitational wave observatories will detect a Universe of unseen black holes in the merging process over a broad spectrum of mass. Computing facilities will permit new high-resolution simulations with a deeper physical analysis of the main phenomena occurring at different scales. Given these development lines, we first sketch a panorama of the main instrumental developments expected in the next thirty years, dealing not only with electromagnetic radiation, but also from a multi-messenger perspective that includes gravitational waves, neutrinos, and cosmic rays. We then present how the new instrumentation will make it possible to foster advances in our present understanding of galaxies and quasars. We focus on selected scientific themes that are hotly debated today, in some cases advancing conjectures on the solution of major problems that may become solved in the next 30 years. Keywords: galaxy evolution – quasars – cosmology – supermassive black holes – black hole physics 1 INTRODUCTION: TOWARD MULTIMESSENGER ASTRONOMY The development of astronomy in the second half of the XXth century followed two major lines of improvement: the increase in light gathering power (i.e., the ability to detect fainter objects), and the extension of the frequency domain in the electromagnetic spectrum beyond the traditional optical domain.
    [Show full text]
  • THE NONLINEAR MATTER POWER SPECTRUM1 Online Material
    The Astrophysical Journal, 665:887– 898, 2007 August 20 A # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE NONLINEAR MATTER POWER SPECTRUM1 Zhaoming Ma Department of Astronomy and Astrophysics and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637; [email protected] Received 2006 October 6; accepted 2007 April 30 ABSTRACT We modify the public PM code developed by Anatoly Klypin and Jon Holtzman to simulate cosmologies with arbitrary initial power spectra and the equation of state of dark energy. With this tool in hand, we perform the follow- ing studies on the matter power spectrum. With an artificial sharp peak at k 0:2 h MpcÀ1 in the initial power spec- trum, we find that the position of the peak is not shifted by nonlinear evolution. An upper limit of the shift at the level of 0.02% is achieved by fitting the power spectrum local to the peak using a power law plus a Gaussian. We also find that the existence of a peak in the linear power spectrum would boost the nonlinear power at all scales evenly. This is contrary to what the HKLM scaling relation predicts, but roughly consistent with that of the halo model. We construct dark energy models with the same linear power spectra today but different linear growth histories. We demonstrate that their nonlinear power spectra differ at the level of the maximum deviation of the corresponding linear power spectra in the past. Similarly, two constructed dark energy models with the same growth histories result in consistent nonlinear power spectra.
    [Show full text]
  • Planck Early Results. XVIII. the Power Spectrum of Cosmic Infrared Background Anisotropies
    A&A 536, A18 (2011) Astronomy DOI: 10.1051/0004-6361/201116461 & c ESO 2011 Astrophysics Planck early results Special feature Planck early results. XVIII. The power spectrum of cosmic infrared background anisotropies Planck Collaboration: P. A. R. Ade74, N. Aghanim48,M.Arnaud60, M. Ashdown58,4, J. Aumont48, C. Baccigalupi72,A.Balbi30, A. J. Banday78,8,65,R.B.Barreiro55, J. G. Bartlett3,56,E.Battaner80, K. Benabed49, A. Benoît47,J.-P.Bernard78,8, M. Bersanelli27,42,R.Bhatia5,K.Blagrave7,J.J.Bock56,9, A. Bonaldi38, L. Bonavera72,6,J.R.Bond7,J.Borrill64,76, F. R. Bouchet49, M. Bucher3,C.Burigana41, P. Cabella30, J.-F. Cardoso61,3,49, A. Catalano3,59, L. Cayón20, A. Challinor52,58,11, A. Chamballu45,L.-YChiang51,C.Chiang19,P.R.Christensen69,31,D.L.Clements45, S. Colombi49, F. Couchot63, A. Coulais59, B. P. Crill56,70, F. Cuttaia41,L.Danese72,R.D.Davies57,R.J.Davis57,P.deBernardis26,G.deGasperis30,A.deRosa41, G. de Zotti38,72, J. Delabrouille3, J.-M. Delouis49, F.-X. Désert44,H.Dole48, S. Donzelli42,53,O.Doré56,9,U.Dörl65, M. Douspis48, X. Dupac34, G. Efstathiou52,T.A.Enßlin65,H.K.Eriksen53, F. Finelli41, O. Forni78,8, P. Fosalba50, M. Frailis40, E. Franceschi41, S. Galeotta40, K. Ganga3,46,M.Giard78,8, G. Giardino35, Y. Giraud-Héraud3, J. González-Nuevo72,K.M.Górski56,82,J.Grain48, S. Gratton58,52, A. Gregorio28, A. Gruppuso41,F.K.Hansen53, D. Harrison52,58,G.Helou9, S. Henrot-Versillé63, D. Herranz55, S. R. Hildebrandt9,62,54,E.Hivon49, M. Hobson4,W.A.Holmes56, W. Hovest65,R.J.Hoyland54,K.M.Huffenberger81, A.
    [Show full text]
  • Clusters, Cosmology and Reionization from the SZ Power Spectrum
    Clusters, Cosmology and Reionization from the SZ Power Spectrum Shaw et al. (10,11) Reichardt, LS, Zahn + (11) Zahn, Reichardt, LS + (11) Collaborators: D. Nagai, D. Rudd (Yale), G. Holder (McGill), Suman Bhattacharya (LANL), O. Zahn (Berkeley), O. Dore (Caltech), the SPT team. Tremendous recent progress measuring the CMB damping tail Small scales provide additional constraints Keisler+ on ★ Helium abundance ★ ns & running ★ neutrinos ..and beyond thermal & kinetic SZ CMB lensing CIB (dusty galaxies) Radio sources Reichardt+ 11 ..and beyond thermal & kinetic SZ CMB lensing CIB (dusty galaxies) Radio sources Reichardt+ 11 primordial signal secondaries & E.G. foregrounds Statistical detection of the SZE by searching for anisotropy power at small angular scales primary cmb thermal SZ kinetic SZ Amplitude of SZ power spectrum is particularly sensitive to matter power spectrum normalization simulated tsz map (Shaw+, 09) 10deg Sensitive to both the abundance of collapsed structures and the thermal pressure of the intra-cluster medium Halo model approach to calculating the tSZ power spectrum Calculate SZ power spectrum by integrating the mass function over M and z, weighted by cluster signal at a given angular scale. zmax dV Mmax dn(M, z) C = g2 dz dM y (M, z) 2 l ν dz dM | l | 0 0 volume integral cluster mass function Fourier transform of projected gas thermal pressure profiles Where does tSZ power come from? distribution of power at ell = 3000 (~3.6’) 10% 50% 90% Shaw+ (10) Low mass, high redshift contribution significant. Modelling the tSZ Power Spectrum Simple parameterized model, calibrated to observations and including cosmological scaling [Shaw+ (10), Ostriker+ (05)] ★ Gas resides in hydrostatic equilibrium in NFW dark matter halos with polytropic EoS ★ Assume some gas has radiatively cooled + formed stars.
    [Show full text]
  • Using the Microlensing Technique, Astronomers Discover an Earth-Like Planet Outside Our Solar System
    S&TR July/August 2006 11 Using the microlensing technique, astronomers discover an Earth-like planet outside our solar system. OOKING out to the vastness of the L night sky, stargazers often ponder questions about the universe, many wondering if planets like ours can be found somewhere out there. But teasing out the details in astronomical data that point to a possible Earth-like planet is exceedingly difficult. To find an extrasolar planet—a planet that circles a star other than the Sun— astrophysicists have in the past searched for Doppler shifts, changes in the wavelength emitted by an object because of its motion. When an astronomical object moves toward an observer on Earth, the light it emits becomes higher in frequency and shifts to the blue end of the spectrum. When the object moves away from the observer, its light becomes lower in frequency and shifts to the red end. By measuring these changes in wavelength, astrophysicists can precisely calculate how quickly objects are moving toward or away from Earth. When This artist’s rendition shows the Earth-like extrasolar planet discovered in 2005. (Reprinted courtesy of the European Southern Observatory.) Lawrence Livermore National Laboratory 12 An Earth-Like Extrasolar Planet S&TR July/August 2006 a giant planet orbits a star, the planet’s About the New Planet we consider the number of stars out there,” gravitational pull on the star produces a According to Livermore astrophysicist Cook says, “the fact that we stumbled on small (meters-per-second) back-and-forth Kem Cook, OGLE-2005-BLG-290-Lb is a one small planet means that thousands Doppler shift in the star’s light.
    [Show full text]
  • Cosmological Structure Formation with Modified Gravity
    Cosmological Structure Formation with Modified Gravity A THESIS SUBMITTED TO THE UNIVERSITY OF MANCHESTER FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN THE FACULTY OF ENGINEERING AND PHYSICAL SCIENCES 2015 Samuel J. Cusworth School of Physics and Astronomy 2 Simulations with Modified Gravity Contents Abstract . 10 Declarations . 11 Acknowledgements . 12 The Author . 14 Supporting Publications . 15 1 Introduction 17 1.1 Introduction to Modern Cosmology . 17 1.1.1 Cosmological Principle . 17 1.1.2 Introduction to General Relativity . 18 1.1.3 Einstein’s Equations from an Action Principle . 20 1.2 Concordance Cosmology . 21 1.2.1 Background Cosmology . 21 1.2.2 The Perturbed ΛCDM universe . 23 1.2.3 Non-linear Structure Formation . 27 1.3 Observational Cosmology . 30 1.3.1 SN1a . 30 1.3.2 CMB . 30 1.3.3 Galaxy Clusters . 33 1.4 f(R) as Dark Energy . 34 1.4.1 Gravitational Field Equations . 35 1.4.2 Einstein Frame . 36 Samuel Cusworth 3 CONTENTS 1.4.3 Screening Mechanism . 37 1.4.4 Viable Models . 39 2 Simulations of Structure Formation 43 2.1 Initial Condition Generation . 44 2.2 N-body Solvers . 45 2.2.1 Tree-Based Methods . 46 2.2.2 Particle Mesh Methods . 47 2.2.3 Adaptive Grid Methods . 49 2.3 Hydrodynamics . 50 2.3.1 Smoothed Particle Hydrodynamics . 51 2.4 Measuring Large Scale Structure Statistics . 54 2.4.1 Matter Power Spectrum . 54 2.4.2 Cluster Mass Function . 55 2.5 Known Limitations . 59 2.5.1 Choice of Initial Conditions .
    [Show full text]
  • On Gravitational Energy in Newtonian Theories
    On Gravitational Energy in Newtonian Theories Neil Dewar Munich Center for Mathematical Philosophy LMU Munich, Germany James Owen Weatherall Department of Logic and Philosophy of Science University of California, Irvine, USA Abstract There are well-known problems associated with the idea of (local) gravitational energy in general relativity. We offer a new perspective on those problems by comparison with Newto- nian gravitation, and particularly geometrized Newtonian gravitation (i.e., Newton-Cartan theory). We show that there is a natural candidate for the energy density of a Newtonian gravitational field. But we observe that this quantity is gauge dependent, and that it cannot be defined in the geometrized (gauge-free) theory without introducing further structure. We then address a potential response by showing that there is an analogue to the Weyl tensor in geometrized Newtonian gravitation. 1. Introduction There is a strong and natural sense in which, in general relativity, there are metrical de- grees of freedom|including purely gravitational, i.e., source-free degrees of freedom, such as gravitational waves|that can influence the behavior of other physical systems. And yet, if one attempts to associate a notion of local energy density with these metrical degrees of freedom, one quickly encounters (well-known) problems.1 For instance, consider the following simple argument that there cannot be a smooth ten- Email address: [email protected] (James Owen Weatherall) 1See, for instance, Misner et al. (1973, pp. 466-468), for a classic argument that there cannot be a local notion of energy associated with gravitation in general relativity; see also Choquet-Brouhat (1983), Goldberg (1980), and Curiel (2017) for other arguments and discussion.
    [Show full text]
  • Exact and Perturbed Friedmann-Lemaıtre Cosmologies
    Exact and Perturbed Friedmann-Lemaˆıtre Cosmologies by Paul Ullrich A thesis presented to the University of Waterloo in fulfilment of the thesis requirement for the degree of Master of Mathematics in Applied Mathematics Waterloo, Ontario, Canada, 2007 °c Paul Ullrich 2007 I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. ii Abstract In this thesis we first apply the 1+3 covariant description of general relativity to analyze n-fluid Friedmann- Lemaˆıtre (FL) cosmologies; that is, homogeneous and isotropic cosmologies whose matter-energy content consists of n non-interacting fluids. We are motivated to study FL models of this type as observations sug- gest the physical universe is closely described by a FL model with a matter content consisting of radiation, dust and a cosmological constant. Secondly, we use the 1 + 3 covariant description to analyse scalar, vec- tor and tensor perturbations of FL cosmologies containing a perfect fluid and a cosmological constant. In particular, we provide a thorough discussion of the behaviour of perturbations in the physically interesting cases of a dust or radiation background. iii Acknowledgements First and foremost, I would like to thank Dr. John Wainwright for his patience, guidance and support throughout the preparation of this thesis. I also would like to thank Dr. Achim Kempf and Dr. C. G. Hewitt for their time and comments. iv Contents 1 Introduction 1 1.1 Cosmological Models .
    [Show full text]
  • Arxiv:1804.03516V1 [Physics.Gen-Ph] 4 Apr 2018 ∗ Mi:[email protected] Email: Hc Erhtemglei Lusadmauelgtcre Ihdura with Curves Years
    April 2018 On the Origin and Nature of Dark Matter P.H. Frampton∗ Brasenose College, Oxford OX1 4AJ, UK Abstract It is discussed how the ideas of entropy and the second law of thermodynamics, conceived long ago during the nineteenth century, underly why cosmological dark matter exists and originated in the first three years of the universe in the form of primordial black holes, a very large number of which have many solar masses including up to the supermassive black holes at the centres of galaxies. Certain upper bounds on dark astrophysical objects with many solar masses based on analysis of the CMB spectrum and published in the literature are criticised. For completeness we discuss WIMPs and axions which are leading particle theory candidates for the constituents of dark matter. The PIMBHs (Primordial Intermediate Mass Black Holes) with many solar masses should be readily detectable in microlensing experiments which search the Magallenic Clouds and measure light curves with durations of from one year up to several years. arXiv:1804.03516v1 [physics.gen-ph] 4 Apr 2018 ∗email: [email protected] Introduction We assume Newton’s universal law for the gravitational force F between every two point particles GM1M2 F = (1) R2 where G is a constant, M1, M2 are the two masses and R is the separation, to be valid at the scale of galaxies and clusters of galaxies. Then there is overwhelming observational evidence [1, 2] for the existence of dark matter which does not radiate electromagnetically but which, by assumption, interacts gravitationally according to Eq.(1).
    [Show full text]