Annual Report 2018
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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. -
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. -
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. -
News from ICTP Autumn—Winter 2019 04 Features
14 8 News from ICTP Autumn—Winter 2019 04 Features 04 Farewell and Thank You 06 Leadership Inspired by Salam As Fernando Quevedo winds down his term as ICTP director, he shares the insights he has gained during his 10 years of leadership 12 Nurturing Latin American Science ICTP assists with region’s research roadmap 14 Dirac Winners 2019 15 Diploma Graduation Ceremony 2019 The Abdus Salam International Centre for Theoretical 16 Research Highlights Physics (ICTP) is governed by the United Nations Educational, Scientific and Cultural Organization (UNESCO), the International Atomic Energy Agency 16 Greenhouse Warming Complicates (IAEA), and Italy. It is a UNESCO category 1 institute. El Niño Predictions News from ICTP is a bi-annual publication designed to keep scientists and staff informed on past 18 Open Access, Curated Data and future activities at ICTP and initiatives in their Provides New Resource at ICTP home countries. The text may be reproduced freely with due credit to the source. 19 Separating The Data From The Noise ICTP on the web: www.ictp.it Follow us on Facebook, Twitter, YouTube, Flickr, Instagram 20 News Briefs ICTP Public Information Office Strada Costiera, 11 22 In Memoriam I-34151 Trieste Italy [email protected] ISSN 2222-6923 Farewell and Russia, Cuba, Peru, Chile, Ecuador, Venezuela, Colombia, Dominican Republic, as well as several regions of China, Thank You India, South Africa, Argentina, Brazil and Mexico, to mention some. Science is naturally an international endeavor and ICTP excels at implementing this in the most inclusive, As I approach the end of my tenure as ICTP director, I unique way. -
Validation of Planck CMB Power Spectrum & Likelihood Code
CMB, gravitational waves and inflation in the Universe Sabino Matarrese Dipartimento di Fisica e Astronomia “Galileo Galilei” Universita’ degli Studi di Padova, Italy INFN, Sezione di Padova Gran Sasso Science Institute, INFN, L’Aquila, Italy [email protected] Inflation as a self consistent model of the very early universe Inflation in the early Universe Inflation (Brout et al. 1978; Starobinski 1980; Kazanas 1980; Sato 1981; Guth 1981; Linde 1982, Albrecht & Steinhardt 1982; etc. ...) is an epoch of accelerated expansion in the early Universe ( ~ 10-34 s after the “Big Bang”) which allows to solve two inconsistencies of the standard Big Bang model. – horizon: why is the Universe so homogeneous and isotropic on average? – flatness: why is the Universe spatial curvature so small even ~ 14 billion years after the Big Bang?) Inflation is based upon the idea that the vacuum energy of a scalar quantum field, dubbed the “inflaton”, dominates over other forms of energy, hence giving rise to a quasi- exponential (de Sitter) expansion, with scale-factor a(t) ≈ exp(Ht) Inflation in the Universe Alan Guth Andrei Linde “The theory of cosmic inflation, proposed and developed by Alan Guth, Andrei Linde and Alexei Starobinsky, has revolutionized our thinking about the universe. This theory extends our physical description of the cosmos to the earliest times, when the universe was only a tiny fraction of a second old. According to this theory, very soon after our universe came into existence it underwent a short-lived phase of exponential expansion. During this brief period the universe expanded by a huge factor – hence the name inflation. -
Ya. B. Zeldovich (1914-1987): Chemist, Nuclear Physicist
Ya. B. Zeldovich (1914-1987) Chemist, Nuclear Physicist, Cosmologist Varun Sahni∗ Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India Ya.B. Zeldovich was a pre-eminent Soviet physicist whose seminal contributions spanned many fields ranging from physical chemistry to nuclear and particle physics, and finally astrophysics and cosmology. March 8, 2014 marks Zeldovich’s birth cen- tenary, and this article attempts to convey the zest with which Zeldovich did science, and the important role he played in fostering and mentoring a whole generation of talented Scientists. I. INTRODUCTION Yakov Borisovich Zeldovich was very talented. His active scientific career included major contributions in fields as diverse as chemical physics (adsorption & catalysis), the theory of shock waves, thermal explosions, the theory of flame propogation, the theory of combustion & detonation, nuclear & particle physics, and, during the latter part of his life: gravitation, astrophysics and cosmology [1]. Zeldovich made key contributions in all these area’s, nurturing a creative and thriving sci- entific community in the process. His total scientific output exceeds 500 research article and arXiv:1403.1537v1 [physics.hist-ph] 4 Mar 2014 20 books. Indeed, after meeting him, the famous English physicist Stephen Hawking wrote “Now I know that you are a real person and not a group of scientists like the Bourbaki”.1 Others have compared his enormously varied scientific output to that of Lord Raleigh who, a hundred years before Zeldovich , worked on fields as varied as optics and engineering. Remarkably Zeldovich never received any formal university education ! He graduated ∗Electronic address: [email protected] [1] Bourbaki was the pseudonym collectively adopted by a group of twentieth century mathematicians who wrote several influential books under this pseudonym on advanced mathematical concepts. -
Le Système Solaire Au Delà Du Système Solaire
LeLe SystèmeSystème solairesolaire Le système solaire (Naissance, vie et mort des étoiles, Soleil, planètes, astéroïdes, planètes naines, ceinture de Kuiper, comètes, nuage d’Oort) Au delà du système solaire (Voie Lactée, exoplanètes, galaxies, groupes de galaxies, trous noirs, Big Bang, Univers) GAP 47 • Olivier Sabbagh • Janvier 2015 Le Système solaire, la Galaxie, l’Univers I Introduction AVERTISSEMENT AUX LECTEURS : Ce document étudie tous les aspects du système solaire et, bien au-delà, replace cet ensemble dans notre Galaxie, celle-ci dans les groupes de galaxies, puis le tout dans l’univers. Nous évoquerons aussi quelques notions sur les trous noirs et le « Big Bang ». Par contre les informations concernant les planètes seront évoquées assez sommairement dans la mesure où sont déjà rédigés des textes spécifiques sur chacune des planètes : Mercure, Vénus la Terre, Mars, Jupiter, Saturne, Uranus, Neptune, les planètes naines, ainsi que les Instruments de l’Astronomie et la Conquête spatiale. A) Naissance d’une étoile – Présence d’une nébuleuse La naissance des étoiles ou formation stellaire, voire stellogénèse ou stellogonie, est un domaine de recherche en astrophysique qui consiste en l'étude des modes de formation des étoiles et des systèmes planétaires. Les étoiles en formation sont fréquemment appelées "étoiles jeunes". En cosmologie, la formation des étoiles n’a lieu que durant la période de l’univers nommée « ère stellifère ». Selon le scénario actuellement admis, confirmé par l'observation, les étoiles se forment en groupe à partir de la contraction gravitationnelle d'une nébuleuse, un nuage de gaz et de poussière, qui se fragmente en plusieurs cœurs protostellaires. -
Qnas with Alan Guth
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: What was your reaction to the 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 Imaging of Cosmic Extragalactic Polarization 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. -
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. -
Gamov Very Short
Andrei Linde The distance from Earth to the edge of the observable part of the universe is about 46.5 billion light years, or 4.4 x 1028 cm, in any direction. It contains about 1090 elementary particles. The total mass is about 1050 tons. When the universe was born, its mass was greater, more than 1080 tons. Where did it come from? Can we play the movie back? What was before the Big Bang? We still do not know, but have some ideas based on inflation and quantum cosmology Why is our universe so uniform? Why is it not exactly uniform? Why is it isotropic (same in all directions)? Why all of its parts started expanding simultaneously? Why is it flat (! = 1)? Why is it so large? Answered by inflation In the Beginning there was… INFLATION Alan Guth Alexei Starobinsky Andrei Linde Vyatcheslav Mukhanov solves many problems of the old Big Bang theory, and explains how the whole universe could be created from less than a milligram of matter One of the Einstein equations for the empty universe with vacuum energy density V0 (cosmological constant) is a˙ 2 V 2 H2 = = 0 a 3 ✓ ◆ It has a solution describing an exponentially growing (inflating) universe: Ht a = a0 e The total vacuum energy of such universe grows even faster, as volume 3Ht E = E0 e If eventually this vacuum state decays, it produces exponentially many elementary particles with exponentially large energy. Problem solved! Alan Guth 1980 The simplest inflationary model AL 1983 Eternal Inflation 33 l 10− cm ⇠ 5 m 10− g ⇠ 1010000000000 in ANY units of length In this theory, original inhomogeneities are stretched away, but new ones are produced from quantum fluctuations amplified during the exponential growth of the universe. -
Natuurkundige Voordrachten 2015 - 2016 Nieuwe Reeks No
NATUURKUNDIGE VOORDRACHTEN 2015 - 2016 NIEUWE REEKS NO. 94 Jaarboek 2015 - 2016 van de KONINKLIJKE MAATSCHAPPIJ VOOR NATUURKUNDE onder de zinspreuk Diligentia Beschermvrouwe Bestuurders Hare Koninklijke Hoogheid Prof. dr. P.J. Sterk, voorzitter Prinses Beatrix der Nederlanden Mw. dr. M.J. Blankwater, secretaris ledenbestand en convocaties Drs. A.E.R. Kalff, secretaris bestuurszaken Erelid Dr. ir. J.G. Vogtländer, penningmeester Prof. dr. R. van Furth Dr. H. Weijma Prof. ir. P. Hoogeboom Mr. J.W. Andringa Prof. dr. K.H. Kuijken DILIGENTIA • Lange Voorhout 5 • 's-Gravenhage Opgericht 1793 • www.natuurwetenschappen-diligentia.nl Natuurkundige voordrachten I Nieuwe reeks 94 Voorwoord Met gepaste trots presenteert het bestuur voor kwaliteit en soms ook curiositeit van de manuscrip- de tweede keer een jaarboek dat in eigen beheer ten op. Het werd alleszins de moeite waard geacht is opgemaakt en volledig in kleur is gedrukt. De om de oude jaarboeken in gescande vorm digitaal positieve reacties op de vorige uitgave waren een beschikbaar te krijgen. Eén van de bestuursleden, stimulans om op de ingeslagen weg door te gaan. Peter Hoogeboom, is daarmee bezig. Het is een fors Daarbij is het streven opgepakt om het jaarboek karwei, maar inmiddels zijn er al zo'n 60 jaarboeken zo snel mogelijk na afloop van het verenigingsjaar van de nieuwe reeks online beschikbaar, namelijk gereed te hebben, liefst al bij de aanvang van het alle lezingen vanaf 1965. Behalve de mogelijkheid nieuwe lezingenseizoen. Dat is deze keer redelijk om complete jaarboeken te downloaden, zijn de gelukt, maar of we daarin vaker slagen, is ook bijdragen in deze boeken ook via de sprekerslijst afhankelijk van de snelheid waarmee de laatste toegankelijk. -
The Scientific Legacy of Stephen Hawking (1942—2018)
1 VOLUME IV ISSUE 1 NEWS 2018 TATA INSTITUTE OF FUNDAMENTAL RESEARCH CELEBRATING THE UNITY OF SCIENCE : ICTS TURNS 10 4–7 January, 2018 | Discussion Meeting ICTS at Ten This is the tenth year of ICTS—TIFR since it came Over the course of this meeting, speakers from into existence on August 2, 2007. ICTS has now around the world gave broad perspective talks grown to a team of fifteen faculty members across different themes in the theoretical sciences: studying various areas in the theoretical sciences. Astrophysics and Cosmology, String theory and Over 150 programs and discussion meetings have Quantum Gravity, Mathematics, Theoretical ICTS at Ten been held. Computer Science, Condensed Matter and Celebrating the unity of Science Statistical Physics, and Physical Biology. A discussion meeting, ICTS at Ten, was held to celebrate the occasion. It was an opportunity to These areas reflect ICTS’ present profile as well The talks were held at the Chandrasekhar reflect on the journey thus far, and to go ahead as the directions it would grow into in the coming auditorium of the ICTS Campus located in north with renewed energy into our second decade, years. The talks, by a galaxy of distinguished Bangalore and were attended by over 200 through a small celebratory scientific gathering. researchers, shed light on some exciting frontier participants. ■ The theme of the meeting was ‘Celebrating the questions in these areas. Unity of Science’. www.icts.res.in 2 | ICTS NEWS | VOLUME IV | ISSUE 1 2018 3 Below here and on the next page, are a few 7 January, 2018 | Public Lecture and Panel Discussion 11 January, 2018 | ICTS Vishveshwara Lecture 14 January, 2018 | Public Lecture & Movie glimpses from the discussion meeting, ICTS at Ten.