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Expanding Space, Quasars and St. Augustine's Fireworks
Universe 2015, 1, 307-356; doi:10.3390/universe1030307 OPEN ACCESS universe ISSN 2218-1997 www.mdpi.com/journal/universe Article Expanding Space, Quasars and St. Augustine’s Fireworks Olga I. Chashchina 1;2 and Zurab K. Silagadze 2;3;* 1 École Polytechnique, 91128 Palaiseau, France; E-Mail: [email protected] 2 Department of physics, Novosibirsk State University, Novosibirsk 630 090, Russia 3 Budker Institute of Nuclear Physics SB RAS and Novosibirsk State University, Novosibirsk 630 090, Russia * Author to whom correspondence should be addressed; E-Mail: [email protected]. Academic Editors: Lorenzo Iorio and Elias C. Vagenas Received: 5 May 2015 / Accepted: 14 September 2015 / Published: 1 October 2015 Abstract: An attempt is made to explain time non-dilation allegedly observed in quasar light curves. The explanation is based on the assumption that quasar black holes are, in some sense, foreign for our Friedmann-Robertson-Walker universe and do not participate in the Hubble flow. Although at first sight such a weird explanation requires unreasonably fine-tuned Big Bang initial conditions, we find a natural justification for it using the Milne cosmological model as an inspiration. Keywords: quasar light curves; expanding space; Milne cosmological model; Hubble flow; St. Augustine’s objects PACS classifications: 98.80.-k, 98.54.-h You’d think capricious Hebe, feeding the eagle of Zeus, had raised a thunder-foaming goblet, unable to restrain her mirth, and tipped it on the earth. F.I.Tyutchev. A Spring Storm, 1828. Translated by F.Jude [1]. 1. Introduction “Quasar light curves do not show the effects of time dilation”—this result of the paper [2] seems incredible. -
Cosmic Age Problem Revisited in the Holographic Dark Energy Model ∗ Jinglei Cui, Xin Zhang
中国科技论文在线 http://www.paper.edu.cn Physics Letters B 690 (2010) 233–238 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb Cosmic age problem revisited in the holographic dark energy model ∗ Jinglei Cui, Xin Zhang Department of Physics, College of Sciences, Northeastern University, Shenyang 110004, China article info abstract Article history: Because of an old quasar APM 08279 + 5255 at z = 3.91, some dark energy models face the challenge of Received 18 April 2010 the cosmic age problem. It has been shown by Wei and Zhang [H. Wei, S.N. Zhang, Phys. Rev. D 76 (2007) Received in revised form 18 May 2010 063003, arXiv:0707.2129 [astro-ph]] that the holographic dark energy model is also troubled with such a Accepted 20 May 2010 cosmic age problem. In order to accommodate this old quasar and solve the age problem, we propose in Available online 24 May 2010 this Letter to consider the interacting holographic dark energy in a non-flat universe. We show that the Editor: T. Yanagida cosmic age problem can be eliminated when the interaction and spatial curvature are both involved in Keywords: the holographic dark energy model. Holographic dark energy © 2010 Elsevier B.V. All rights reserved. Cosmic age problem 1. Introduction of quantum gravity could be taken into account. It is commonly believed that the holographic principle [16] is just a fundamental The fact that our universe is undergoing accelerated expansion principle of quantum gravity. Based on the effective quantum field has been confirmed by lots of astronomical observations such as theory, Cohen et al. -
8.962 General Relativity, Spring 2017 Massachusetts Institute of Technology Department of Physics
8.962 General Relativity, Spring 2017 Massachusetts Institute of Technology Department of Physics Lectures by: Alan Guth Notes by: Andrew P. Turner May 26, 2017 1 Lecture 1 (Feb. 8, 2017) 1.1 Why general relativity? Why should we be interested in general relativity? (a) General relativity is the uniquely greatest triumph of analytic reasoning in all of science. Simultaneity is not well-defined in special relativity, and so Newton's laws of gravity become Ill-defined. Using only special relativity and the fact that Newton's theory of gravity works terrestrially, Einstein was able to produce what we now know as general relativity. (b) Understanding gravity has now become an important part of most considerations in funda- mental physics. Historically, it was easy to leave gravity out phenomenologically, because it is a factor of 1038 weaker than the other forces. If one tries to build a quantum field theory from general relativity, it fails to be renormalizable, unlike the quantum field theories for the other fundamental forces. Nowadays, gravity has become an integral part of attempts to extend the standard model. Gravity is also important in the field of cosmology, which became more prominent after the discovery of the cosmic microwave background, progress on calculations of big bang nucleosynthesis, and the introduction of inflationary cosmology. 1.2 Review of Special Relativity The basic assumption of special relativity is as follows: All laws of physics, including the statement that light travels at speed c, hold in any inertial coordinate system. Fur- thermore, any coordinate system that is moving at fixed velocity with respect to an inertial coordinate system is also inertial. -
Aspects of Spatially Homogeneous and Isotropic Cosmology
Faculty of Technology and Science Department of Physics and Electrical Engineering Mikael Isaksson Aspects of Spatially Homogeneous and Isotropic Cosmology Degree Project of 15 credit points Physics Program Date/Term: 02-04-11 Supervisor: Prof. Claes Uggla Examiner: Prof. Jürgen Fuchs Karlstads universitet 651 88 Karlstad Tfn 054-700 10 00 Fax 054-700 14 60 [email protected] www.kau.se Abstract In this thesis, after a general introduction, we first review some differential geom- etry to provide the mathematical background needed to derive the key equations in cosmology. Then we consider the Robertson-Walker geometry and its relation- ship to cosmography, i.e., how one makes measurements in cosmology. We finally connect the Robertson-Walker geometry to Einstein's field equation to obtain so- called cosmological Friedmann-Lema^ıtre models. These models are subsequently studied by means of potential diagrams. 1 CONTENTS CONTENTS Contents 1 Introduction 3 2 Differential geometry prerequisites 8 3 Cosmography 13 3.1 Robertson-Walker geometry . 13 3.2 Concepts and measurements in cosmography . 18 4 Friedmann-Lema^ıtre dynamics 30 5 Bibliography 42 2 1 INTRODUCTION 1 Introduction Cosmology comes from the Greek word kosmos, `universe' and logia, `study', and is the study of the large-scale structure, origin, and evolution of the universe, that is, of the universe taken as a whole [1]. Even though the word cosmology is relatively recent (first used in 1730 in Christian Wolff's Cosmologia Generalis), the study of the universe has a long history involving science, philosophy, eso- tericism, and religion. Cosmologies in their earliest form were concerned with, what is now known as celestial mechanics (the study of the heavens). -
Sacred Rhetorical Invention in the String Theory Movement
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Communication Studies Theses, Dissertations, and Student Research Communication Studies, Department of Spring 4-12-2011 Secular Salvation: Sacred Rhetorical Invention in the String Theory Movement Brent Yergensen University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/commstuddiss Part of the Speech and Rhetorical Studies Commons Yergensen, Brent, "Secular Salvation: Sacred Rhetorical Invention in the String Theory Movement" (2011). Communication Studies Theses, Dissertations, and Student Research. 6. https://digitalcommons.unl.edu/commstuddiss/6 This Article is brought to you for free and open access by the Communication Studies, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Communication Studies Theses, Dissertations, and Student Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. SECULAR SALVATION: SACRED RHETORICAL INVENTION IN THE STRING THEORY MOVEMENT by Brent Yergensen A DISSERTATION Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy Major: Communication Studies Under the Supervision of Dr. Ronald Lee Lincoln, Nebraska April, 2011 ii SECULAR SALVATION: SACRED RHETORICAL INVENTION IN THE STRING THEORY MOVEMENT Brent Yergensen, Ph.D. University of Nebraska, 2011 Advisor: Ronald Lee String theory is argued by its proponents to be the Theory of Everything. It achieves this status in physics because it provides unification for contradictory laws of physics, namely quantum mechanics and general relativity. While based on advanced theoretical mathematics, its public discourse is growing in prevalence and its rhetorical power is leading to a scientific revolution, even among the public. -
Methods of Measuring Astronomical Distances
LASER INTERFEROMETER GRAVITATIONAL WAVE OBSERVATORY - LIGO - =============================== LIGO SCIENTIFIC COLLABORATION Technical Note LIGO-T1200427{v1 2012/09/02 Methods of Measuring Astronomical Distances Sarah Gossan and Christian Ott California Institute of Technology Massachusetts Institute of Technology LIGO Project, MS 18-34 LIGO Project, Room NW22-295 Pasadena, CA 91125 Cambridge, MA 02139 Phone (626) 395-2129 Phone (617) 253-4824 Fax (626) 304-9834 Fax (617) 253-7014 E-mail: [email protected] E-mail: [email protected] LIGO Hanford Observatory LIGO Livingston Observatory Route 10, Mile Marker 2 19100 LIGO Lane Richland, WA 99352 Livingston, LA 70754 Phone (509) 372-8106 Phone (225) 686-3100 Fax (509) 372-8137 Fax (225) 686-7189 E-mail: [email protected] E-mail: [email protected] http://www.ligo.org/ LIGO-T1200427{v1 1 Introduction The determination of source distances, from solar system to cosmological scales, holds great importance for the purposes of all areas of astrophysics. Over all distance scales, there is not one method of measuring distances that works consistently, and as a result, distance scales must be built up step-by-step, using different methods that each work over limited ranges of the full distance required. Broadly, astronomical distance `calibrators' can be categorised as primary, secondary or tertiary, with secondary calibrated themselves by primary, and tertiary by secondary, thus compounding any uncertainties in the distances measured with each rung ascended on the cosmological `distance ladder'. Typically, primary calibrators can only be used for nearby stars and stellar clusters, whereas secondary and tertiary calibrators are employed for sources within and beyond the Virgo cluster respectively. -
The Center for Theoretical Physics: the First 50 Years
CTP50 The Center for Theoretical Physics: The First 50 Years Saturday, March 24, 2018 50 SPEAKERS Andrew Childs, Co-Director of the Joint Center for Quantum Information and Computer CTPScience and Professor of Computer Science, University of Maryland Will Detmold, Associate Professor of Physics, Center for Theoretical Physics Henriette Elvang, Professor of Physics, University of Michigan, Ann Arbor Alan Guth, Victor Weisskopf Professor of Physics, Center for Theoretical Physics Daniel Harlow, Assistant Professor of Physics, Center for Theoretical Physics Aram Harrow, Associate Professor of Physics, Center for Theoretical Physics David Kaiser, Germeshausen Professor of the History of Science and Professor of Physics Chung-Pei Ma, J. C. Webb Professor of Astronomy and Physics, University of California, Berkeley Lisa Randall, Frank B. Baird, Jr. Professor of Science, Harvard University Sanjay Reddy, Professor of Physics, Institute for Nuclear Theory, University of Washington Tracy Slatyer, Jerrold Zacharias CD Assistant Professor of Physics, Center for Theoretical Physics Dam Son, University Professor, University of Chicago Jesse Thaler, Associate Professor, Center for Theoretical Physics David Tong, Professor of Theoretical Physics, University of Cambridge, England and Trinity College Fellow Frank Wilczek, Herman Feshbach Professor of Physics, Center for Theoretical Physics and 2004 Nobel Laureate The Center for Theoretical Physics: The First 50 Years 3 50 SCHEDULE 9:00 Introductions and Welcomes: Michael Sipser, Dean of Science; CTP Peter -
Einstein's Physics
Einstein’s Physics Albert Einstein at Barnes Foundation in Merion PA, c.1947. Photography by Laura Delano Condax; gift to the author from Vanna Condax. Einstein’s Physics Atoms, Quanta, and Relativity Derived, Explained, and Appraised TA-PEI CHENG University of Missouri–St. Louis Portland State University 3 3 Great Clarendon Street, Oxford, OX2 6DP, United Kingdom Oxford University Press is a department of the University of Oxford. It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide. Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries © Ta-Pei Cheng 2013 The moral rights of the author have been asserted Impression: 1 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, by licence or under terms agreed with the appropriate reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above You must not circulate this work in any other form and you must impose this same condition on any acquirer British Library Cataloguing in Publication Data Data available ISBN 978–0–19–966991–2 Printed and bound by CPI Group (UK) Ltd, Croydon, CR0 4YY Links to third party websites are provided by Oxford in good faith and for information only. Oxford disclaims any responsibility for the materials contained in any third party website referenced in this work. -
Finding the Radiation from the Big Bang
Finding The Radiation from the Big Bang P. J. E. Peebles and R. B. Partridge January 9, 2007 4. Preface 6. Chapter 1. Introduction 13. Chapter 2. A guide to cosmology 14. The expanding universe 19. The thermal cosmic microwave background radiation 21. What is the universe made of? 26. Chapter 3. Origins of the Cosmology of 1960 27. Nucleosynthesis in a hot big bang 32. Nucleosynthesis in alternative cosmologies 36. Thermal radiation from a bouncing universe 37. Detecting the cosmic microwave background radiation 44. Cosmology in 1960 52. Chapter 4. Cosmology in the 1960s 53. David Hogg: Early Low-Noise and Related Studies at Bell Lab- oratories, Holmdel, N.J. 57. Nick Woolf: Conversations with Dicke 59. George Field: Cyanogen and the CMBR 62. Pat Thaddeus 63. Don Osterbrock: The Helium Content of the Universe 70. Igor Novikov: Cosmology in the Soviet Union in the 1960s 78. Andrei Doroshkevich: Cosmology in the Sixties 1 80. Rashid Sunyaev 81. Arno Penzias: Encountering Cosmology 95. Bob Wilson: Two Astronomical Discoveries 114. Bernard F. Burke: Radio astronomy from first contacts to the CMBR 122. Kenneth C. Turner: Spreading the Word — or How the News Went From Princeton to Holmdel 123. Jim Peebles: How I Learned Physical Cosmology 136. David T. Wilkinson: Measuring the Cosmic Microwave Back- ground Radiation 144. Peter Roll: Recollections of the Second Measurement of the CMBR at Princeton University in 1965 153. Bob Wagoner: An Initial Impact of the CMBR on Nucleosyn- thesis in Big and Little Bangs 157. Martin Rees: Advances in Cosmology and Relativistic Astro- physics 163. -
Reconciling the Cosmic Age Problem in the Rh = Ct Universe
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Springer - Publisher Connector Eur. Phys. J. C (2014) 74:3090 DOI 10.1140/epjc/s10052-014-3090-1 Regular Article - Theoretical Physics Reconciling the cosmic age problem in the Rh = ct universe H. Yu1,F.Y.Wang1,2,a 1 School of Astronomy and Space Science, Nanjing University, Nanjing 210093, China 2 Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Ministry of Education, Nanjing 210093, China Received: 19 April 2014 / Accepted: 19 September 2014 / Published online: 2 October 2014 © The Author(s) 2014. This article is published with open access at Springerlink.com Abstract Many dark energy models fail to pass the cosmic t0 = 13.82 Gyr in the CDM model [6], but it still suf- age test. In this paper, we investigate the cosmic age problem fers from the cosmic age problem [11,12]. The cosmic age associated with nine extremely old Global Clusters (GCs) problem is that some objects are older than the age of the and the old quasar APM 08279+5255 in the Rh = ct uni- universe at its redshift z. In previous literature, many cos- verse. The age data of these oldest GCs in M31 are acquired mological models have been tested by the old quasar APM from the Beijing–Arizona–Taiwan–Connecticut system with 08279+5255 with age 2.1 ± 0.3 Gyr at z = 3.91 [13,14], up-to-date theoretical synthesis models. They have not been such as the CDM [13,15], the (t) model [16], the inter- used to test the cosmic age problem in the Rh = ct uni- acting dark energy models [12], the generalized Chaplygin verse in previous literature. -
Section 1: Facts and History (PDF)
Section 1 Facts and History Fields of Study 11 Digital Learning 12 Research Laboratories, Centers, and Programs 13 Academic and Research Affiliations 14 Education Highlights 16 Research Highlights 21 Faculty and Staff 30 Faculty 30 Researchers 32 Postdoctoral Scholars 33 Awards and Honors of Current Faculty and Staff 34 MIT Briefing Book 9 MIT’s commitment to innovation has led to a host of Facts and History scientific breakthroughs and technological advances. The Massachusetts Institute of Technology is one of Achievements of the Institute’s faculty and graduates the world’s preeminent research universities, dedi- have included the first chemical synthesis of penicillin cated to advancing knowledge and educating students and vitamin A, the development of inertial guidance in science, technology, and other areas of scholarship systems, modern technologies for artificial limbs, and that will best serve the nation and the world. It is the magnetic core memory that enabled the develop- known for rigorous academic programs, cutting-edge ment of digital computers. Exciting areas of research research, a diverse campus community, and its long- and education today include neuroscience and the standing commitment to working with the public and study of the brain and mind, bioengineering, energy, private sectors to bring new knowledge to bear on the the environment and sustainable development, infor- world’s great challenges. mation sciences and technology, new media, financial technology, and entrepreneurship. William Barton Rogers, the Institute’s founding presi- dent, believed that education should be both broad University research is one of the mainsprings of and useful, enabling students to participate in “the growth in an economy that is increasingly defined by humane culture of the community” and to discover technology. -
Our Cosmic Origins
Chapter 5 Our cosmic origins “In the beginning, the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move”. Douglas Adams, in The Restaurant at the End of the Universe “Oh no: he’s falling asleep!” It’s 1997, I’m giving a talk at Tufts University, and the legendary Alan Guth has come over from MIT to listen. I’d never met him before, and having such a luminary in the audience made me feel both honored and nervous. Especially nervous. Especially when his head started slumping toward his chest, and his gaze began going blank. In an act of des- peration, I tried speaking more enthusiastically and shifting my tone of voice. He jolted back up a few times, but soon my fiasco was complete: he was o↵in dreamland, and didn’t return until my talk was over. I felt deflated. Only much later, when we became MIT colleagues, did I realize that Alan falls asleep during all talks (except his own). In fact, my grad student Adrian Liu pointed out that I’ve started doing the same myself. And that I’ve never noticed that he does too because we always go in the same order. If Alan, I and Adrian sit next to each other in that order, we’ll infallibly replicate a somnolent version of “the wave” that’s so popular with soccer spectators. I’ve come to really like Alan, who’s as warm as he’s smart. Tidiness isn’t his forte, however: the first time I visited his office, I found most of the floor covered with a thick layer of unopened mail.