The Book of the Universes by the Same Author
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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. -
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. -
Green Belt Slowly Coming Together
Kemano, Kemano, Kemano She loved the outdoors 1 I Bountiful harvest Reaction to the death of the ~ Vicki Kryklywyj, the heart and soul / /Northern B.C, Winter Games project keeps rolling in by,fax, mail of local hikers, is / / athletes cleaned up in Williams,, and personal delivery/NEWS A5 : remembered/COMMUNITY B1 j /Lake this year/SPORTS Cl I • i! ':i % WEDNESDAY FEBROARY 151 1995 I'ANDAR. /iiii ¸ :¸!ilii if!// 0 re n d a t i p of u n kn own ice b e rg" LIKE ALL deals in the world of tion Corp. effective April 30, the That title is still held by original "They've phoned us and have and the majority of its services, lulose for its Prince Rupert pulp high finance, the proposed amal- transfer of Orenda's forest licorice owners Avenor Inc. of Montreal requested a meeting but there's induding steam and effluent mill for the next two years. gamation of Orenda Forest Pro- must be approved by the provin- and a group of American newspa- been no confirmation of a time treaUnent, are tied to the latter. Even should all of the Orenda duels with a mostly American cial government. per companies. for that meeting," said Archer Avenor also owns and controls pulp fibre end up at Gold River, it company is more complicated There's growing opposition to The partuership built the mill in official Norman Lord from docking facilities and a chipper at still will fall short of the 5130,000 than it first seems. the move to take wood from the the late 1980s but dosed it in the Montreal last week. -
Catalog INTERNATIONAL
اﻟﻤﺆﺗﻤﺮ اﻟﻌﺎﻟﻤﻲ اﻟﻌﺸﺮون ﻟﺪﻋﻢ اﻻﺑﺘﻜﺎر ﻓﻲ ﻣﺠﺎل اﻟﻔﻨﻮن واﻟﺘﻜﻨﻮﻟﻮﺟﻴﺎ The 20th International Symposium on Electronic Art Ras al-Khaimah 25.7833° North 55.9500° East Umm al-Quwain 25.9864° North 55.9400° East Ajman 25.4167° North 55.5000° East Sharjah 25.4333 ° North 55.3833 ° East Fujairah 25.2667° North 56.3333° East Dubai 24.9500° North 55.3333° East Abu Dhabi 24.4667° North 54.3667° East SE ISEA2014 Catalog INTERNATIONAL Under the Patronage of H.E. Sheikha Lubna Bint Khalid Al Qasimi Minister of International Cooperation and Development, President of Zayed University 30 October — 8 November, 2014 SE INTERNATIONAL ISEA2014, where Art, Science, and Technology Come Together vi Richard Wheeler - Dubai On land and in the sea, our forefathers lived and survived in this environment. They were able to do so only because they recognized the need to conserve it, to take from it only what they needed to live, and to preserve it for succeeding generations. Late Sheikh Zayed bin Sultan Al Nahyan viii ZAYED UNIVERSITY Ed unt optur, tet pla dessi dis molore optatiist vendae pro eaqui que doluptae. Num am dis magnimus deliti od estem quam qui si di re aut qui offic tem facca- tiur alicatia veliqui conet labo. Andae expeliam ima doluptatem. Estis sandaepti dolor a quodite mporempe doluptatus. Ustiis et ium haritatur ad quaectaes autemoluptas reiundae endae explaboriae at. Simenis elliquide repe nestotae sincipitat etur sum niminctur molupta tisimpor mossusa piendem ulparch illupicat fugiaep edipsam, conecum eos dio corese- qui sitat et, autatum enimolu ptatur aut autenecus eaqui aut volupiet quas quid qui sandaeptatem sum il in cum sitam re dolupti onsent raeceperion re dolorum inis si consequ assequi quiatur sa nos natat etusam fuga. -
Could Minkowski Have Discovered the Cause of Gravitation Before Einstein?
2 Could Minkowski have discovered the cause of gravitation before Einstein? Vesselin Petkov Abstract There are two reasons for asking such an apparently unanswer- able question. First, Max Born’s recollections of what Minkowski had told him about his research on the physical meaning of the Lorentz transformations and the fact that Minkowski had created the full-blown four-dimensional mathematical formalism of space- time physics before the end of 1907 (which could have been highly improbable if Minkowski had not been developing his own ideas), both indicate that Minkowski might have arrived at the notion of spacetime independently of Poincaré (who saw it as nothing more than a mathematical space) and at a deeper understanding of the basic ideas of special relativity (which Einstein merely postulated) independently of Einstein. So, had he lived longer, Minkowski might have employed successfully his program of regarding four- dimensional physics as spacetime geometry to gravitation as well. Moreover, Hilbert (Minkowski’s closest colleague and friend) had derived the equations of general relativity simultaneously with Ein- stein. Second, even if Einstein had arrived at what is today called Einstein’s general relativity before Minkowski, Minkowski would have certainly reformulated it in terms of his program of geometriz- ing physics and might have represented gravitation fully as the man- ifestation of the non-Euclidean geometry of spacetime (Einstein re- garded the geometrical representation of gravitation as pure math- ematics) exactly like he reformulated Einstein’s special relativity in terms of spacetime. 1 Introduction On January 12, 1909, only several months after his Cologne lecture Space and Time [1], at the age of 44 Hermann Minkowski untimely left this world. -
A Brief History of Gravitational Waves
universe Review A Brief History of Gravitational Waves Jorge L. Cervantes-Cota 1, Salvador Galindo-Uribarri 1 and George F. Smoot 2,3,4,* 1 Department of Physics, National Institute for Nuclear Research, Km 36.5 Carretera Mexico-Toluca, Ocoyoacac, C.P. 52750 Mexico, Mexico; [email protected] (J.L.C.-C.); [email protected] (S.G.-U.) 2 Helmut and Ana Pao Sohmen Professor at Large, Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, 999077 Hong Kong, China 3 Université Sorbonne Paris Cité, Laboratoire APC-PCCP, Université Paris Diderot, 10 rue Alice Domon et Leonie Duquet, 75205 Paris Cedex 13, France 4 Department of Physics and LBNL, University of California; MS Bldg 50-5505 LBNL, 1 Cyclotron Road Berkeley, 94720 CA, USA * Correspondence: [email protected]; Tel.:+1-510-486-5505 Academic Editors: Lorenzo Iorio and Elias C. Vagenas Received: 21 July 2016; Accepted: 2 September 2016; Published: 13 September 2016 Abstract: This review describes the discovery of gravitational waves. We recount the journey of predicting and finding those waves, since its beginning in the early twentieth century, their prediction by Einstein in 1916, theoretical and experimental blunders, efforts towards their detection, and finally the subsequent successful discovery. Keywords: gravitational waves; General Relativity; LIGO; Einstein; strong-field gravity; binary black holes 1. Introduction Einstein’s General Theory of Relativity, published in November 1915, led to the prediction of the existence of gravitational waves that would be so faint and their interaction with matter so weak that Einstein himself wondered if they could ever be discovered. -
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. -
Reversed out (White) Reversed
Berkeley rev.( white) Berkeley rev.( FALL 2014 reversed out (white) reversed IN THIS ISSUE Berkeley’s Space Sciences Laboratory Tabletop Physics Bringing More Women into Physics ALUMNI NEWS AND MORE! Cover: The MAVEN satellite mission uses instrumentation developed at UC Berkeley's Space Sciences Laboratory to explore the physics behind the loss of the Martian atmosphere. It’s a continuation of Berkeley astrophysicist Robert Lin’s pioneering work in solar physics. See p 7. photo credit: Lockheed Martin Physics at Berkeley 2014 Published annually by the Department of Physics Steven Boggs: Chair Anil More: Director of Administration Maria Hjelm: Director of Development, College of Letters and Science Devi Mathieu: Editor, Principal Writer Meg Coughlin: Design Additional assistance provided by Sarah Wittmer, Sylvie Mehner and Susan Houghton Department of Physics 366 LeConte Hall #7300 University of California, Berkeley Berkeley, CA 94720-7300 Copyright 2014 by The Regents of the University of California FEATURES 4 12 18 Berkeley’s Space Tabletop Physics Bringing More Women Sciences Laboratory BERKELEY THEORISTS INVENT into Physics NEW WAYS TO SEARCH FOR GOING ON SIX DECADES UC BERKELEY HOSTS THE 2014 NEW PHYSICS OF EDUCATION AND SPACE WEST COAST CONFERENCE EXPLORATION Berkeley theoretical physicists Ashvin FOR UNDERGRADUATE WOMEN Vishwanath and Surjeet Rajendran IN PHYSICS Since the Space Lab’s inception are developing new, small-scale in 1959, Berkeley physicists have Women physics students from low-energy approaches to questions played important roles in many California, Oregon, Washington, usually associated with large-scale of the nation’s space-based scientific Alaska, and Hawaii gathered on high-energy particle experiments. -
A Brief History of Gravitational Waves
Review A Brief History of Gravitational Waves Jorge L. Cervantes-Cota 1, Salvador Galindo-Uribarri 1 and George F. Smoot 2,3,4,* 1 Department of Physics, National Institute for Nuclear Research, Km 36.5 Carretera Mexico-Toluca, Ocoyoacac, Mexico State C.P.52750, Mexico; [email protected] (J.L.C.-C.); [email protected] (S.G.-U.) 2 Helmut and Ana Pao Sohmen Professor at Large, Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong, China. 3 Université Sorbonne Paris Cité, Laboratoire APC-PCCP, Université Paris Diderot, 10 rue Alice Domon et Leonie Duquet 75205 Paris Cedex 13, France. 4 Department of Physics and LBNL, University of California; MS Bldg 50-5505 LBNL, 1 Cyclotron Road Berkeley, CA 94720, USA. * Correspondence: [email protected]; Tel.:+1-510-486-5505 Abstract: This review describes the discovery of gravitational waves. We recount the journey of predicting and finding those waves, since its beginning in the early twentieth century, their prediction by Einstein in 1916, theoretical and experimental blunders, efforts towards their detection, and finally the subsequent successful discovery. Keywords: gravitational waves; General Relativity; LIGO; Einstein; strong-field gravity; binary black holes 1. Introduction Einstein’s General Theory of Relativity, published in November 1915, led to the prediction of the existence of gravitational waves that would be so faint and their interaction with matter so weak that Einstein himself wondered if they could ever be discovered. Even if they were detectable, Einstein also wondered if they would ever be useful enough for use in science. -
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. -
Collected Writings
THE DOCUMENTS O F TWENTIETH CENTURY ART General Editor, Jack Flam Founding Editor, Robert Motherwell Other titl es in the series available from University of California Press: Flight Out of Tillie: A Dada Diary by Hugo Ball John Elderfield Art as Art: The Selected Writings of Ad Reinhardt Barbara Rose Memo irs of a Dada Dnnnmer by Richard Huelsenbeck Hans J. Kl ein sc hmidt German Expressionism: Dowments jro111 the End of th e Wilhelmine Empire to th e Rise of National Socialis111 Rose-Carol Washton Long Matisse on Art, Revised Edition Jack Flam Pop Art: A Critical History Steven Henry Madoff Co llected Writings of Robert Mothen/le/1 Stephanie Terenzio Conversations with Cezanne Michael Doran ROBERT SMITHSON: THE COLLECTED WRITINGS EDITED BY JACK FLAM UNIVERSITY OF CALIFORNIA PRESS Berkeley Los Angeles Londo n University of Cali fornia Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England © 1996 by the Estate of Robert Smithson Introduction © 1996 by Jack Flam Library of Congress Cataloging-in-Publication Data Smithson, Robert. Robert Smithson, the collected writings I edited, with an Introduction by Jack Flam. p. em.- (The documents of twentieth century art) Originally published: The writings of Robert Smithson. New York: New York University Press, 1979. Includes bibliographical references and index. ISBN 0-520-20385-2 (pbk.: alk. paper) r. Art. I. Title. II. Series. N7445.2.S62A3 5 1996 700-dc20 95-34773 C IP Printed in the United States of Am erica o8 07 o6 9 8 7 6 T he paper used in this publication meets the minimum requirements of ANSII NISO Z39·48-1992 (R 1997) (Per111anmce of Paper) . -
2014 Children and Teens Department Summer Favorites
2014 CHILDREN AND TEENS DEPARTMENT SUMMER FAVORITES , copyright 2014 with permission from Candlewick from with permission 2014 , copyright Firefly July Firefly Illustration from from Illustration 1 PICTURE BOOKS Never turn the page too quickly. Never assume you know what happens next. These are the rules for reading Rules of Summer (Arthur A. Levine, $18.99). In this tale of two brothers’ summertime adventures and mistakes, Shaun Tan creates a world in which meteors are caught like fireflies, robots populate parades, Kazuno Kohara animates the sleeping hours in and a giant rabbit menaces those who leave The Midnight Library (Roaring Brook, $16.99), red socks on the clothesline. Tan’s sweeping a charming tale of the nocturnal life of a library surreal paintings pair with sparse text to create and the librarian who shepherds its animal a world of commonplace marvels that invite patrons. Characters will inspire giggles in young the full participation of the reader. His work readers and ring true to daytime librarians: never confines a reader to a single, easily the loud squirrel musicians, the tortoise who interpretable narrative. Its appeal is part wonder, has plodded only halfway through his tome by part adventure, and part lurking menace. Wildly closing (sunrise). The linocut illustrations’ bold inventive and richly layered, this meditation outlines and minimal color palette add a layer on friendship, childhood, and imagination will of nighttime fantasy and heighten the book’s engage a wide range of readers. The book’s an magic. A sweet homage to librarians, the book adventure in itself, the kind to which one returns also works as a bedtime read, closing with a again and again.