Mukhanov and Starobinsky to Receive $500,000 Gruber Cosmology Prize for Developing Theory of Universe’S Earliest Moments
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Chairman of the Opening Session
The Universe had (probably) an origin: on singularity theorems & quantum fluctuations Emilio Elizalde ICE/CSIC & IEEC Campus UAB, Barcelona Cosmology and the Quantum Vacuum III, Benasque, Sep 4-10, 2016 Some facts (a few rather surprising...) • Adam Riess, NP 2011, at Starmus (Tenerife), about Hubble: • “Hubble obtained the distances and redshifts of distant nebulae…” • “Hubble discovered that the Universe was expanding…” • No mention to Vesto Slipher, an extraordinary astronomer • Brian Schmidt, NP 2011, at Starmus (Tenerife) & Lisa Randall, Harvard U, in Barcelona, about Einstein: SHOES- • “Einstein was the first to think about the possibility of a ‘dark energy’…” Supernovae • No mention to Fritz Zwicky, another extraordinary astronomer • Fritz Zwicky discovered dark matter in the early 1930s while studying how galaxies move within the Coma Cluster • He was also the first to postulate and use nebulae as gravitational lenses (1937) • How easily* brilliant astronomers get dismissed • How easily* scientific myths arise *in few decades How did the “Big Bang” get its name ? http://www.bbc.co.uk/science/space/universe/scientists/fred_hoyle • Sir Fred Hoyle (1915–2001) English astronomer noted primarily for the theory of stellar nucleosynthesis (1946,54 groundbreaking papers) • Work on Britain's radar project with Hermann Bondi and Thomas Gold • William Fowler NP’83: “The concept of nucleosynthesis in stars was first established by Hoyle in 1946” • He found the idea universe had a beginning to be pseudoscience, also arguments for a creator, “…for it's an irrational process, and can't be described in scientific terms”; “…belief in the first page of Genesis” • Hoyle-Gold-Bondi 1948 steady state theory, “creation or C-field” • BBC radio's Third Programme broadcast on 28 Mar 1949: “… for this to happen you would need such a Big Bang!” Thus: Big Bang = Impossible blow!! But now: Big Bang ≈ Inflation ! • Same underlying physics as in steady state theory, “creation or C-field” • Richard C. -
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. -
What Is the Universe Made Of? How Old Is the Universe?
What is the Universe made of? How old is it? Charles H. Lineweaver University of New South Wales ABSTRACT For the past 15 years most astronomers have assumed that 95% of the Universe was in some mysterious form of cold dark matter. They also assumed that the cosmo- logical constant, ΩΛ, was Einstein’s biggest blunder and could be ignored. However, recent measurements of the cosmic microwave background combined with other cos- mological observations strongly suggest that 75% of the Universe is made of cosmo- logical constant (vacuum energy), while only 20% is made of non-baryonic cold dark matter. Normal baryonic matter, the stuff most physicists study, makes up about 5% of the Universe. If these results are correct, an unknown 75% of the Universe has been identified. Estimates of the age of the Universe depend upon what it is made of. Thus, our new inventory gives us a new age for the Universe: 13.4 ± 1.6 Gyr. “The history of cosmology shows us that in every age devout people believe that they have at last discovered the true nature of the Universe.” (E. Harrison in Cosmology: The Science of the Universe 1981) 1 Progress A few decades ago cosmology was laughed at for being the only science with no data. Cosmology was theory-rich but data-poor. It attracted armchair enthusiasts spouting speculations without data to test them. It was the only science where the errors could be kept in the exponents – where you could set the speed of light c =1, not for dimensionless convenience, but because the observations were so poor that it didn’t matter. -
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. -
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. -
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. -
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. -
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 -
Tinkering with Time the NEW TIME TRAVELERS: a JOURNEY to the on Our FRONTIERS of PHYSICS by DAVID TOOMEY Bookshelf W
BOOKS & ARTS Tinkering with time THE NEW TIME TRAVELERS: A JOURNEY TO THE On our FRONTIERS OF PHYSICS BY DAVID TOOMEY bookshelf W. W. Norton & Co.: 2007. 320 pp. $25.95 Years ago, David Toomey picked up H. G. Wells’ moving clocks tick slowly, making time travel The Time Machine and couldn’t put it down. to the future possible. We now know a number The Mathematics of He was most interested in the drawing-room of solutions to Einstein’s equations of general Egypt, Mesopotamia, discussion between the time traveller and his relativity (1915) that are sufficiently twisted to China, India, and Islam: friends in which time as a fourth dimension was allow time travel to the past: Kurt Gödel’s 1949 A Sourcebook discussed, but wanted to know more about just rotating universe; the Morris–Thorne–Yurtsever edited by Victor J. Katz how that time machine might work. Toomey was wormhole (1988); the Tipler–van Stockum infinite therefore delighted to learn that that drawing- rotating cylinder, moving cosmic strings (myself), Princeton Univ. Press: room conversation continues today — this time the rotating black-hole interior (Brandon Carter), 2007. 685 pp. $75 among physicists. a Roman ring of wormholes (Matt Visser), the We’re aware that Toomey captures well the personalities Everett–Alcubierre warp drive, my and Li–Xin Li’s the ancient cultures of the ‘new time travelers’ — those physicists self-creating universe; Amos Ori’s torus; and were mathematically interested in whether time travel to the past is others. The book discusses all of these. advanced. Now possible — from Stephen Hawking’s sense of But can a time machine really be constructed? translations of early texts humour to Kip Thorne’s penchant for placing Hawking, like one of the time traveller’s sceptical from five key regions are scientific bets. -
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. -
ACCRETION INTO and EMISSION from BLACK HOLES Thesis By
ACCRETION INTO AND EMISSION FROM BLACK HOLES Thesis by Don Nelson Page In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 1976 (Submitted May 20, 1976) -ii- ACKNOHLEDG:-IENTS For everything involved during my pursuit of a Ph. D. , I praise and thank my Lord Jesus Christ, in whom "all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities--all things have been created through Him and for Him. And He is before all things, and in Him all things hold together" (Colossians 1: 16-17) . But He is not only the Creator and Sustainer of the universe, including the physi cal laws which rule and their dominion the spacetime manifold and its matter fields ; He is also my personal Savior, who was "wounded for our transgressions , ... bruised for our iniquities, .. and the Lord has lald on Him the iniquity of us all" (Isaiah 53:5-6). As the Apostle Paul expressed it shortly after Isaiah ' s prophecy had come true at least five hundred years after being written, "God demonstrates His own love tmvard us , in that while we were yet sinners, Christ died for us" (Romans 5 : 8) . Christ Himself said, " I have come that they may have life, and have it to the full" (John 10:10) . Indeed Christ has given me life to the full while I have been at Caltech, and I wish to acknowledge some of the main blessings He has granted: First I thank my advisors , KipS. -
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.