DOCSLIB.ORG

Qnas with Alan Guth

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Qnas with Alan Guth QNAS QNAS QnAs with Alan Guth Paul Gabrielsen Science Writer The announcement in March 2014 that a few minutes of the history of the universe. telescope near the South Pole had detected Inflation comes before all that. possible evidence of gravitational waves PNAS: Whatwasyourreactiontothe brought renewed attention to inflationary results of the BICEP2 experiment, suggesting theory, which describes the earliest moments evidence of gravitational waves? of the universe. According to inflationary Guth: I was incredibly impressed that they theory, exotic matter present at the birth of had discovered what, at that time, appeared to the universe exerted repulsive gravitational be a completely unambiguous signal of gravi- effects, driving extremely rapid expansion of tational radiation coming from the early uni- the universe and leaving behind traces of verse, presumably from inflation. Since then gravitational waves in the cosmic background things have changed. The observations were radiation. National Academy of Sciences certainly a tour de force, but when other people member Alan Guth, a physicist at the Mas- looked more carefully at the ways the experi- sachusetts Institute of Technology, first out- ment could go wrong, the possibility that the lined inflationary theory in 1981 and has since signal could have been entirely due to dust been working out the details and implications couldnotberuledout.SorightnowIthink Alan Guth. Image courtesy of Jenny Guth. of the theory with his colleagues. The South it is waiting to be confirmed. I still hope that it Pole experiment, called BICEP2 (Background willturnouttobereal,butatthispointIthink ImagingofCosmicExtragalacticPolarization we don’tknowifitwasarealsignalofgravita- Henry Tye got himself interested in a class of 2), is undergoing further scrutiny to assess tional radiation from the early universe or not. particle theories called Grand Unified Theo- the possible influence of cosmic dust on the PNAS: Apart from BICEP2, what evidence ries. And he asked me whether these theories gravitational wave signal. Guth, however, supports inflation theory? would predict that magnetic monopoles points to other evidence that illustrates how Guth: Since the proposal of inflation, there should exist, a magnetic monopole being a inflationary theory can accurately describe the have been a growing number of measure- particle with a net magnetic charge, north earliest moments of matter and energy in the ments that have supported exactly what in- or south. We came to the conclusion that if universe. In May 2014 Guth, along with flation predicts. One of those is the prediction we combined conventional cosmology with fellow inflationary theorists Andrei Linde about the overall mass density of the uni- Grand Unified Theories, the universe would and Alexei Starobinsky, was awarded the verse. When inflation was first proposed, be predicted to be swimming with magnetic Kavli Prize in astrophysics. To commemorate the measured value seemed to be lower than monopoles, but there couldn’t possibly be the honor, PNAS spoke with Guth. what inflation predicted, by a factor of about nearly that many. So Henry and I started PNAS: What does winning the Kavli Prize 3 or 4. Then, in 1998 astronomers discovered thinking about whether or not it’s possible mean to you? that the universe is not slowing down under to change anything to make the Grand Uni- Guth: I think the prize helps to solidify the the influence of gravity but rather is acceler- fied Theories compatible with cosmology. This acceptance of inflationary theory, which has ating. This acceleration gives a demonstration inquiry ultimately led to the idea of inflation. a great deal of evidence behind it now, and that gravity can act repulsively and not just FromthetimeIwasakidIwasquite I’m glad to see the institutions of the world attractively. But once we knew the universe fascinated with the idea that mathematics can agreeing with that conclusion. was accelerating, we had to invent a new kind describe the real world. In high school a friend PNAS: Which came first, inflation or the of matter to be responsible for that. And of mine was doing a physics experiment, big bang? that’swhatwecallthe“dark energy,” which taking a yardstick and punching holes in it at Guth: The word “big bang” is used incon- we now think makes up most of the energy in different locations, and pivoting the yardstick sistently. In the eyes of most of the public, the the universe. Once the dark energy is added around those holes, letting it swing back and “big bang” indicates the instant of creation of to the other matter that we already knew forth, and measuring the frequency of the the universe. But in fact we don’t even know about, the empirical estimates of the mass swinging as a function of where the hole was. if the universe had an instant of creation. Nev- density of the universe agree precisely with I had learned just enough Newtonian me- ertheless, if the phrase “big bang” is used this what inflation predicts. So what had been a chanics to calculate what the answer was way, then certainly it comes before anything. significant problem for inflation has turned supposed to be. We took my friend’sdata However, among scientists, the big bang the- into an important success. and a slide rule and plugged in the numbers oryisreallyonlythetheoryoftheaftermath PNAS: Why have you devoted your life to to compare his data with my calculation, and of a bang. It’s a theory of how the early uni- unraveling the secrets of the universe? we were both shocked to see that it actually verse expanded and cooled. It includes, for Guth: I certainly did not set out to invent worked: his measured frequencies were very example, a description of how the lightest a new theory of cosmology. When I was a close to what my formula predicted. It was chemical elements were produced in the first postdoc at Cornell, a fellow postdoc named great fun. Maybe that’s what hooked me. www.pnas.org/cgi/doi/10.1073/pnas.1417149111 PNAS Early Edition | 1of1 Downloaded by guest on September 30, 2021.
Load more

Recommended publications
  • Arxiv:0711.0760V3 [Hep-Th]
    DBI N-flation John Ward1 Department of Physics and Astronomy, University of Victoria, Victoria BC, V8P 1A1, Canada Abstract We investigate DBI inflation using N multiple branes and show how the configuration is equivalent to a single wrapped D5-brane with flux. We then show how 1/N corrections can be implemented, and we examine the sound speed and levels of non-Gaussianities in two distinct cases. For models with constant warping we find that the non-Gaussian amplitude is bounded from above (as a function of γ). For AdS backgrounds we find that the signature is generally large and positive, although is no longer globally defined over the full phase space. We then investigate an inflationary mechanism using a representation cascade, whereby the transition from a reducible representation to the irrep drives inflation. arXiv:0711.0760v3 [hep-th] 26 Nov 2007 [email protected] 1 Introduction In the absence of any direct test of string theory, cosmology remains the best laboratory with which to test string theoretic models [1]. Over the past few years we have witnessed cosmology become a precision science, with COBE, WMAP and SDSS [2] providing crucial support for the flatness of the universe, the existence of dark energy and for a period of cosmic inflation. Whilst the dark energy puzzle remains an outstanding problem for theoretical physics in general [3], inflation has been a carefully developed paradigm with many explicit models. Unfortunately as far as inflationary model building is concerned, there are still many problems to be resolved. Particularly since many of the models suffer from super-Planckian VEV’s for the inflaton field [1], and therefore find themselves in a region where quantum gravity effects are non-negligible.
    [Show full text]
  • Inflation, Large Branes, and the Shape of Space
    Inflation, Large Branes, and the Shape of Space Brett McInnes National University of Singapore email: [email protected] ABSTRACT Linde has recently argued that compact flat or negatively curved spatial sections should, in many circumstances, be considered typical in Inflationary cosmologies. We suggest that the “large brane instability” of Seiberg and Witten eliminates the negative candidates in the context of string theory. That leaves the flat, compact, three-dimensional manifolds — Conway’s platycosms. We show that deep theorems of Schoen, Yau, Gromov and Lawson imply that, even in this case, Seiberg-Witten instability can be avoided only with difficulty. Using a specific cosmological model of the Maldacena-Maoz type, we explain how to do this, and we also show how the list of platycosmic candidates can be reduced to three. This leads to an extension of the basic idea: the conformal compactification of the entire Euclidean spacetime also has the topology of a flat, compact, four-dimensional space. arXiv:hep-th/0410115v2 19 Oct 2004 1. Nearly Flat or Really Flat? Linde has recently argued [1] that, at least in some circumstances, we should regard cosmological models with flat or negatively curved compact spatial sections as the norm from an Inflationary point of view. Here we wish to argue that cosmic holography, in the novel form proposed by Maldacena and Maoz [2], gives a deep new interpretation of this idea, and also sharpens it very considerably to exclude the negative case. This focuses our attention on cosmological models with flat, compact spatial sections. Current observations [3] show that the spatial sections of our Universe [as defined by observers for whom local isotropy obtains] are fairly close to being flat: the total density parameter Ω satisfies Ω = 1.02 0.02 at 95% confidence level, if we allow the imposition ± of a reasonable prior [4] on the Hubble parameter.
    [Show full text]
  • Eternal Inflation and Its Implications
    IOP PUBLISHING JOURNAL OF PHYSICS A: MATHEMATICAL AND THEORETICAL J. Phys. A: Math. Theor. 40 (2007) 6811–6826 doi:10.1088/1751-8113/40/25/S25 Eternal inflation and its implications Alan H Guth Center for Theoretical Physics, Laboratory for Nuclear Science, and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA E-mail: [email protected] Received 8 February 2006 Published 6 June 2007 Online at stacks.iop.org/JPhysA/40/6811 Abstract Isummarizetheargumentsthatstronglysuggestthatouruniverseisthe product of inflation. The mechanisms that lead to eternal inflation in both new and chaotic models are described. Although the infinity of pocket universes produced by eternal inflation are unobservable, it is argued that eternal inflation has real consequences in terms of the way that predictions are extracted from theoretical models. The ambiguities in defining probabilities in eternally inflating spacetimes are reviewed, with emphasis on the youngness paradox that results from a synchronous gauge regularization technique. Although inflation is generically eternal into the future, it is not eternal into the past: it can be proven under reasonable assumptions that the inflating region must be incomplete in past directions, so some physics other than inflation is needed to describe the past boundary of the inflating region. PACS numbers: 98.80.cQ, 98.80.Bp, 98.80.Es 1. Introduction: the successes of inflation Since the proposal of the inflationary model some 25 years ago [1–4], inflation has been remarkably successful in explaining many important qualitative and quantitative properties of the universe. In this paper, I will summarize the key successes, and then discuss a number of issues associated with the eternal nature of inflation.
    [Show full text]
  • 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.
    [Show full text]
  • Is There Eternal Inflation in the Cosmic Landscape ?
    Is there eternal inflation in the cosmic landscape ? Henry Tye Cornell University hep-th/0611148 ArXiv:0708.4374 [hep-th] with Qing-Guo Huang, ArXiv:0803.0663 [hep-th] with Dan Wohns and Yang Zhang, ArXiv:0811.3753 [hep-th] IPMU, 04/01/09 Expansion of the universe k ρm ρr H2 =Λ+ + + a2 a3 a4 • a(t) = the cosmic scale factor ~ size of universe • H = Hubble constant =(da/dt)/a • Λ = dark energy ~ cosmological constant ~ effective potential • k = curvature • ρm = matter density at initial time • ρr = radiation density at initial time • H = constant ⇒ a = eHt Inflation BRIEF ARTICLE THE AUTHOR 1 (1) d = s(Λc)/ξ +1 ∼ ∼ 1 ∼ −1/4 (2) ξ s(Λs) Λs ms (3) d>60 BRIEF ARTICLE (4) T (n) " T0/n THE AUTHOR 4 (5) Γ = msT (6) n ∼ 1/Hs 1 Eternal Inflation Ht 3 3Ht (7) (1) a(t) " e → V = a(t) " e τ > 1/H Suppose the universe is sitting at a local minimum, with a ln L (2)lifetime longer than the Hubble lntime:g ∼− L = −e Then the number of Hubble patches will increase −Si (3) exponentially. Even after some Hubble patchesαi have∼ e decayed, there would be many remaining Hubble patches (4) that continue to inflate. |βij| < αi (5) Eternal inflation impliesφi = thatϕi/f i somewhere in the universe (outside our horizon),d −1 (6) Γt ∼ n Γ0 inflation is still happening today. T (A → B)T (B → C) (7) T (A → C)= ∼ T0/2 T (A → B)+T (B → C) −S (8) ΓA→B = ΓB→C = Γ0 ∼ e 2 (9) ΓA→C ∼ ΓA→BΓB→C = Γ0 1 1 2 (10) tA→C = tA→B + tB→C = + ∼ → → 1 ΓA B ΓB C Γ0 Γ0 (11) Γ → = A C 2 −S (12) Γ(1) = Γ0 ∼ e − (13) Γ(2) ∼ e 2S − (14) Γ(2) ∼ e S − (15) Γ(n) ∼ e S (16) +H2φ2 2 2 (17) H = U/3MP 1 Flux compactification in Type II string theory where all moduli of the 6-dim.
    [Show full text]
  • 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.
    [Show full text]
  • The Kavli Prize in Astrophysics 2014
    THE KAVLI PRIZE IN ASTROPHYSICS 2014 The Norwegian Academy of Science and Letters has decided to award the Kavli Prize in Astrophysics for 2014 to Alan H. Guth Massachusetts Institute of Technology, Cambridge, MA, USA Andrei D. Linde Stanford University, CA, USA Alexei A. Starobinsky Landau Institute for Theoretical Physics, Russian Academy of Sciences, Moscow, Russia “for pioneering the theory of cosmic inflation” The theory of cosmic inflation, proposed astounding success, the Big Bang theory These two fundamental problems were and developed by Alan Guth, Andrei suffers from two major shortcomings: the elegantly solved in one fell swoop by Alan Linde and Alexei Starobinsky, has revo- “horizon” and the “flatness” problems. Guth in a paper entitled “Inflationary lutionized our thinking about the uni- Cosmic inflation solves them both. universe: A possible solution to the hori- verse. This theory extends our physical zon and flatness problems” published in description of the cosmos to the earliest As the universe expanded it cooled. Today 1981. Guth hypothesized that the uni- times, when the universe was only a tiny it is bathed in a sea of microwave radia- verse was initially trapped in a peculiar fraction of a second old. According to this tion, the heat left over from the Big Bang. state (the “false vacuum”) from which it theory, very soon after our universe came At first sight, the near uniformity of this decayed, in the process expanding expo- into existence it underwent a short-lived microwave background across the sky nentially and liberating the energy pres- phase of exponential expansion. During implies a disturbing contradiction: oppo- ent in our universe today.
    [Show full text]
  • 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
    [Show full text]
  • Brief Answers to the Big Questions
    Copyright © 2018 by Spacetime Publications Limited Foreword copyright © 2018 by Eddie Redmayne Introduction copyright © 2018 by Kip Thorne Afterword copyright © 2018 by Lucy Hawking All rights reserved. Published in the United States by Bantam Books, an imprint of Random House, a division of Penguin Random House LLC, New York. BANTAM BOOKS and the HOUSE colophon are registered trademarks of Penguin Random House LLC. Published in the United Kingdom by John Murray (Publishers), a Hachette UK Company. Photograph of the adult Stephen Hawking © Andre Pattenden Hardback ISBN 9781984819192 Ebook ISBN 9781984819208 randomhousebooks.com Text design by Craig Burgess, adapted for ebook Cover design: Dan Rembert Cover image: © Shutterstock v5.3.2 ep Contents Cover Title Page Copyright A Note from the Publisher Foreword: Eddie Redmayne An Introduction: Kip Thorne Why We Must Ask the Big Questions Chapter 1: Is There a God? Chapter 2: How Did It All Begin? Chapter 3: Is There Other Intelligent Life in the Universe? Chapter 4: Can We Predict the Future? Chapter 5: What Is Inside a Black Hole? Chapter 6: Is Time Travel Possible? Chapter 7: Will We Survive on Earth? Chapter 8: Should We Colonise Space? Chapter 9: Will Artificial Intelligence Outsmart Us? Chapter 10: How Do We Shape the Future? Afterword: Lucy Hawking Acknowledgements By Stephen Hawking About the Author A Note from the Publisher Stephen Hawking was regularly asked for his thoughts on the “big questions” of the day by scientists, tech entrepreneurs, senior business figures, political leaders and the general public. Stephen maintained an enormous personal archive of his responses, which took the form of speeches, interviews and essays.
    [Show full text]
  • Qnas with Alan Guth
    QNAS QNAS QnAs with Alan Guth Paul Gabrielsen Science Writer The announcement in March 2014 that a few minutes of the history of the universe. telescope near the South Pole had detected Inflation comes before all that. possible evidence of gravitational waves PNAS: Whatwasyourreactiontothe brought renewed attention to inflationary results of the BICEP2 experiment, suggesting theory, which describes the earliest moments evidence of gravitational waves? of the universe. According to inflationary Guth: I was incredibly impressed that they theory, exotic matter present at the birth of had discovered what, at that time, appeared to the universe exerted repulsive gravitational be a completely unambiguous signal of gravi- effects, driving extremely rapid expansion of tational radiation coming from the early uni- the universe and leaving behind traces of verse, presumably from inflation. Since then gravitational waves in the cosmic background things have changed. The observations were radiation. National Academy of Sciences certainly a tour de force, but when other people member Alan Guth, a physicist at the Mas- looked more carefully at the ways the experi- sachusetts Institute of Technology, first out- ment could go wrong, the possibility that the lined inflationary theory in 1981 and has since signal could have been entirely due to dust been working out the details and implications couldnotberuledout.SorightnowIthink Alan Guth. Image courtesy of Jenny Guth. of the theory with his colleagues. The South it is waiting to be confirmed. I still hope that it Pole experiment, called BICEP2 (Background willturnouttobereal,butatthispointIthink ImagingofCosmicExtragalacticPolarization we don’tknowifitwasarealsignalofgravita- Henry Tye got himself interested in a class of 2), is undergoing further scrutiny to assess tional radiation from the early universe or not.
    [Show full text]
  • 2012-2013 Chair James Rosenzweig
    Department of Physics Astronomy ANNUAL REPORT 2013 219728_AnnualReport.indd 1 11/18/13 4:02 PM UCLA Physics and Astronomy Department 2012-2013 Chair James Rosenzweig Chief Administrative Officer Will Spencer Feature Article Eric Hudson Editorial Assistants Corinna Koehnenkamp, D.L. MacLaughlan-Dumes, Laurie Ultan-Thomas Design Mary Jo Robertson © 2013 by the Regents of the University of California All rights reserved. Requests for additional copies of the publication UCLA Department of Physics and Astronomy 2012-2013 Annual Report may be sent to: Office of the Chair UCLA Department of Physics and Astronomy 430 Portola Plaza Box 951547 Los Angeles California 90095-1547 For more information on the Department see our website: http://www.pa.ucla.edu/ UCLA DEPARTMENT OF PHYSICS & ASTRONOMY 219728_AnnualReport.indd 2 11/18/13 4:02 PM Department of Physics Astronomy& 2013 Annual Report UNIVERSITY OF CALIFORNIA, LOS ANGELES 219728_AnnualReport.indd 3 11/18/13 4:02 PM CONTENTS FEATURE ARTICLE: P.7 “Harnessing quantum interactions for the future of science and technology” GIVING TO THE DEPARTMENT P.15 UCLA ALUMNI P.18 ASTRONOMY & ASTROPHYSICS P.19 ASTROPARTICLE PHYSICS P.31 PHYSICS RESEARCH HIGHLIGHTS P.37 PHYSICS & ASTRONOMY FACULTY/RESEARCHERS P.60 DEPARTMENT NEWS P.61 OUTREACH-ASTRONOMY LIVE P. 64 GRADUATION 2012-13 P.66 219728_AnnualReport.indd 4 11/18/13 4:02 PM Message from the Chair As Chair of the UCLA Department of Physics and Astronomy, it is with pride that I present to you our 2013 Annual Report. This document is intended to give an overview of the departmental accomplishments recorded in the last year, extending from recog- nition of faculty excellence in teaching and research, to the welcoming of new members to our ranks.
    [Show full text]
  • 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.
    [Show full text]