Challenges for Understanding the Quantum Universe and the Role of Computing at the Extreme Scale I
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The Future of Fundamental Physics
The Future of Fundamental Physics Nima Arkani-Hamed Abstract: Fundamental physics began the twentieth century with the twin revolutions of relativity and quantum mechanics, and much of the second half of the century was devoted to the con- struction of a theoretical structure unifying these radical ideas. But this foundation has also led us to a number of paradoxes in our understanding of nature. Attempts to make sense of quantum mechanics and gravity at the smallest distance scales lead inexorably to the conclusion that space- Downloaded from http://direct.mit.edu/daed/article-pdf/141/3/53/1830482/daed_a_00161.pdf by guest on 23 September 2021 time is an approximate notion that must emerge from more primitive building blocks. Further- more, violent short-distance quantum fluctuations in the vacuum seem to make the existence of a macroscopic world wildly implausible, and yet we live comfortably in a huge universe. What, if anything, tames these fluctuations? Why is there a macroscopic universe? These are two of the central theoretical challenges of fundamental physics in the twenty-½rst century. In this essay, I describe the circle of ideas surrounding these questions, as well as some of the theoretical and experimental fronts on which they are being attacked. Ever since Newton realized that the same force of gravity pulling down on an apple is also responsible for keeping the moon orbiting the Earth, funda- mental physics has been driven by the program of uni½cation: the realization that seemingly disparate phenomena are in fact different aspects of the same underlying cause. By the mid-1800s, electricity and magnetism were seen as different aspects of elec- tromagnetism, and a seemingly unrelated phenom- enon–light–was understood to be the undulation of electric and magnetic ½elds. -
Quantum Field Theory*
Quantum Field Theory y Frank Wilczek Institute for Advanced Study, School of Natural Science, Olden Lane, Princeton, NJ 08540 I discuss the general principles underlying quantum eld theory, and attempt to identify its most profound consequences. The deep est of these consequences result from the in nite number of degrees of freedom invoked to implement lo cality.Imention a few of its most striking successes, b oth achieved and prosp ective. Possible limitation s of quantum eld theory are viewed in the light of its history. I. SURVEY Quantum eld theory is the framework in which the regnant theories of the electroweak and strong interactions, which together form the Standard Mo del, are formulated. Quantum electro dynamics (QED), b esides providing a com- plete foundation for atomic physics and chemistry, has supp orted calculations of physical quantities with unparalleled precision. The exp erimentally measured value of the magnetic dip ole moment of the muon, 11 (g 2) = 233 184 600 (1680) 10 ; (1) exp: for example, should b e compared with the theoretical prediction 11 (g 2) = 233 183 478 (308) 10 : (2) theor: In quantum chromo dynamics (QCD) we cannot, for the forseeable future, aspire to to comparable accuracy.Yet QCD provides di erent, and at least equally impressive, evidence for the validity of the basic principles of quantum eld theory. Indeed, b ecause in QCD the interactions are stronger, QCD manifests a wider variety of phenomena characteristic of quantum eld theory. These include esp ecially running of the e ective coupling with distance or energy scale and the phenomenon of con nement. -
Astrophysics with Terabytes
Astrophysics with Terabytes Alex Szalay The Johns Hopkins University Jim Gray Microsoft Research Living in an Exponential World • Astronomers have a few hundred TB now – 1 pixel (byte) / sq arc second ~ 4TB – Multi-spectral, temporal, … _ 1PB • They mine it looking for 1000 new (kinds of) objects or more of interesting ones (quasars), 100 density variations in 400-D space 10 correlations in 400-D space 1 • Data doubles every year 0.1 2000 1995 1990 1985 1980 1975 1970 CCDs Glass The Challenges Exponential data growth: Distributed collections Soon Petabytes Data Collection Discovery Publishing and Analysis New analysis paradigm: New publishing paradigm: Data federations, Scientists are publishers Move analysis to data and Curators Why Is Astronomy Special? • Especially attractive for the wide public • Community is not very large • It has no commercial value – No privacy concerns, freely share results with others – Great for experimenting with algorithms • It is real and well documented – High-dimensional (with confidence intervals) – Spatial, temporal • Diverse and distributed – Many different instruments from many different places and many different times • The questions are interesting • There is a lot of it (soon petabytes) The Virtual Observatory • Premise: most data is (or could be online) • The Internet is the world’s best telescope: – It has data on every part of the sky – In every measured spectral band: optical, x-ray, radio.. – As deep as the best instruments (2 years ago). – It is up when you are up – The “seeing” is always great – It’s a smart telescope: links objects and data to literature on them • Software became the capital expense – Share, standardize, reuse. -
Things You Need to Know About Big Data
Critical Missions Are Built On NetApp NetApp’s Big Data solutions deliver high performance computing, full motion video (FMV) and intelligence, surveillance and reconnaissance (ISR) capabilities to support national safety, defense and intelligence missions and scientific research. UNDERWRITTEN BY To learn more about how NetApp and VetDS can solve your big data challenges, call us at 919.238.4715 or visit us online at VetDS.com. ©2011 NetApp. All rights reserved. Specifications are subject to change without notice. NetApp, the NetApp logo, and Go further, faster are trademarks or registered trademarks of NetApp, Inc. in the United States and/or other countries. All other brands or products are trademarks or registered trademarks of their respective holders and should be treated as such. Critical Missions Are Things You NeedBuilt On NetApp to Know About Big Data NetApp’s Big Data solutions deliver high Big data has been making big news in fields rangingperformance from astronomy computing, full motionto online video advertising. (FMV) and intelligence, surveillance and By Joseph Marks The term big data can be difficult to pin down because it reconnaissanceshows up in (ISR) so capabilities many toplaces. support Facebook national safety, defense and intelligence crunches through big data on your user profile and friend networkmissions and to scientific deliver research. micro-targeted ads. Google does the same thing with Gmail messages, Search requests and YouTube browsing. Companies including IBM are sifting through big data from satellites, the Global Positioning System and computer networks to cut down on traffic jams and reduce carbon emissions in cities. And researchers are parsing big data produced by the Hubble Space Telescope, the Large Hadron Collider and numerous other sources to learn more about the nature and origins of the universe. -
Introduction to General Relativity
INTRODUCTION TO GENERAL RELATIVITY Gerard 't Hooft Institute for Theoretical Physics Utrecht University and Spinoza Institute Postbox 80.195 3508 TD Utrecht, the Netherlands e-mail: [email protected] internet: http://www.phys.uu.nl/~thooft/ Version November 2010 1 Prologue General relativity is a beautiful scheme for describing the gravitational ¯eld and the equations it obeys. Nowadays this theory is often used as a prototype for other, more intricate constructions to describe forces between elementary particles or other branches of fundamental physics. This is why in an introduction to general relativity it is of importance to separate as clearly as possible the various ingredients that together give shape to this paradigm. After explaining the physical motivations we ¯rst introduce curved coordinates, then add to this the notion of an a±ne connection ¯eld and only as a later step add to that the metric ¯eld. One then sees clearly how space and time get more and more structure, until ¯nally all we have to do is deduce Einstein's ¯eld equations. These notes materialized when I was asked to present some lectures on General Rela- tivity. Small changes were made over the years. I decided to make them freely available on the web, via my home page. Some readers expressed their irritation over the fact that after 12 pages I switch notation: the i in the time components of vectors disappears, and the metric becomes the ¡ + + + metric. Why this \inconsistency" in the notation? There were two reasons for this. The transition is made where we proceed from special relativity to general relativity. -
"Eternal" Questions in the XX-Century Theoretical Physics V
Philosophical roots of the "eternal" questions in the XX-century theoretical physics V. Ihnatovych Department of Philosophy, National Technical University of Ukraine “Kyiv Polytechnic Institute”, Kyiv, Ukraine e-mail: [email protected] Abstract The evolution of theoretical physics in the XX century differs significantly from that in XVII-XIX centuries. While continuous progress is observed for theoretical physics in XVII-XIX centuries, modern physics contains many questions that have not been resolved despite many decades of discussion. Based upon the analysis of works by the founders of the XX-century physics, the conclusion is made that the roots of the "eternal" questions by the XX-century theoretical physics lie in the philosophy used by its founders. The conclusion is made about the need to use the ideas of philosophy that guided C. Huygens, I. Newton, W. Thomson (Lord Kelvin), J. K. Maxwell, and the other great physicists of the XVII-XIX centuries, in all areas of theoretical physics. 1. Classical Physics The history of theoretical physics begins in 1687 with the work “Mathematical Principles of Natural Philosophy” by Isaac Newton. Even today, this work is an example of what a full and consistent outline of the physical theory should be. It contains everything necessary for such an outline – definition of basic concepts, the complete list of underlying laws, presentation of methods of theoretical research, rigorous proofs. In the eighteenth century, such great physicists and mathematicians as Euler, D'Alembert, Lagrange, Laplace and others developed mechanics, hydrodynamics, acoustics and nebular mechanics on the basis of the ideas of Newton's “Principles”. -
The Mechanical Problems in the Corpus of Aristotle
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications, Classics and Religious Studies Department Classics and Religious Studies July 2007 The Mechanical Problems in the Corpus of Aristotle Thomas Nelson Winter University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/classicsfacpub Part of the Classics Commons Winter, Thomas Nelson, "The Mechanical Problems in the Corpus of Aristotle" (2007). Faculty Publications, Classics and Religious Studies Department. 68. https://digitalcommons.unl.edu/classicsfacpub/68 This Article is brought to you for free and open access by the Classics and Religious Studies at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications, Classics and Religious Studies Department by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Th e Mechanical Problems in the Corpus of Aristotle Th omas N. Winter Lincoln, Nebraska • 2007 Translator’s Preface. Who Wrote the Mechanical Problems in the Aristotelian Corpus? When I was translating the Mechanical Problems, which I did from the TLG Greek text, I was still in the fundamentalist authorship mode: that it survives in the corpus of Aristotle was then for me prima facie Th is paper will: evidence that Aristotle was the author. And at many places I found in- 1) off er the plainest evidence yet that it is not Aristotle, and — 1 dications that the date of the work was apt for Aristotle. But eventually, 2) name an author. I saw a join in Vitruvius, as in the brief summary below, “Who Wrote Th at it is not Aristotle does not, so far, rest on evidence. -
President's Column
AAAS Publication for the members N of the Americanewsletter Astronomical Society September/October 2010, Issue 154 CONTENTS President's Column Debra Meloy Elmegreen, [email protected] 2 Congratulations to all of us in the astronomical community on the completion of the Decadal From the Survey! Two years after the National Research Council organized the Astro2010 Committee to begin its arduous process, the report “New Worlds, New Horizons in Astronomy and Astrophysics” Executive Office is complete. In fact, as I write this article the public roll-out is underway at the Keck Center of the National Academies in Washington, DC. This was truly a community effort, and we should all be proud of it and feel ownership of it. The federal funding agencies and Congress widely view the 3 astronomy decadal process as a model for other disciplines to emulate, and it is extremely important for us to embrace it. Editor, The Astrophysical We are embarking on a period of unprecedented opportunities for astronomical research, thanks to great advances in technology, theory, and observations, and the report presents an exciting Journal Letters and balanced set of science-driven priorities within the framework of realistic budget scenarios. The Astro2010 committee comprised 23 astronomers, selected by the National Academies based on community solicitation of suggested names, who were assisted by panels on different science 4 disciplines, space- and ground-based activities, and study groups on the astronomical infrastructure; these subcommittees had a membership of nearly 200 astronomers from the US astronomical Journals Update community. The Survey report and the panel reports are the culmination of a careful and deliberate consideration of science goals, projects and missions and on the whole astronomical enterprise, based in part on the distillation of over 450 community-submitted white papers, over 100 proposals for 6 research activities, briefings from federal agencies, and 17 Town Halls, along with other federal and international reports. -
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General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) N79-28092 (NASA-T"1-80294) A SEARCH FOR X-RAY FM13STON FROM RICH CLUSTF.'+S, F.XTFNt1Et'• F1ALOS AWIND CLUSTERS, AND SUPERCLUSTERS (NASA) 37 p rinclas HC AOl/ N F A01 CSCL 038 G3/90 29952 Technical Memorandum 80294 A Search for X- Ray Emission from Riche Clusters, Extended Halos around Clusters, and Superclusters S. H. Pravdo, E. A. Boldt, F. E. Marshall, J. Mc Kee, R. F. Mushotzky, B. W. Smith, and G. Reichert JUNE 1979 A Naticnal Aeronautics and Snn,^ Administration "` Goddard Space Flight Center Greenbelt, Maryland 20771 A SEARCH FOR X-RAY EMISSION FROM RICH CLUSTERS, EXTENDED HALOS AROUND CLUSTERS, ANU SUPERCLUSTERS • S.H Pravdo E A Boldt, F.E Marshall J. McKee R.F Mushotzky , B.W. -
Green Open Access
PUBLISHED VERSION F. Aharonian ... G. Rowell ... et al Detection of VHE gamma-ray emission from the distant blazar 1ES 1101-232 with HESS and broadband characterisation Astronomy and Astrophysics, 2007; 470(2):475-489 © ESO 2007. Article published by EDP Sciences Originally published: http://dx.doi.org/10.1051/0004-6361:20077057 PERMISSIONS https://www.aanda.org/index.php?option=com_content&view=article&id=863&Itemid=2 95 Green Open Access The Publisher and A&A encourage arXiv archiving or self-archiving of the final PDF file of the article exactly as published in the journal and without any period of embargo. 25 September 2018 http://hdl.handle.net/2440/49607 A&A 470, 475–489 (2007) Astronomy DOI: 10.1051/0004-6361:20077057 & c ESO 2007 Astrophysics Detection of VHE gamma-ray emission from the distant blazar 1ES 1101-232 with HESS and broadband characterisation F. Aharonian1, A. G. Akhperjanian2, A. R. Bazer-Bachi3, M. Beilicke4,W.Benbow1,D.Berge1,, K. Bernlöhr1,5, C. Boisson6,O.Bolz1, V. Borrel3,I.Braun1, E. Brion7,A.M.Brown8,R.Bühler1, I. Büsching9, T. Boutelier17, S. Carrigan1,P.M.Chadwick8, L.-M. Chounet10, G. Coignet11, R. Cornils4,L.Costamante1,23,B.Degrange10, H. J. Dickinson8, A. Djannati-Ataï12,L.O’C.Drury13, G. Dubus10,K.Egberts1, D. Emmanoulopoulos14, P. Espigat12, C. Farnier15,F.Feinstein15, E. Ferrero14, A. Fiasson15, G. Fontaine10,Seb.Funk5, S. Funk1, M. Füßling5, Y. A. Gallant15,B.Giebels10, J. F. Glicenstein7,B.Glück16,P.Goret7, C. Hadjichristidis8, D. Hauser1, M. Hauser14, G. Heinzelmann4,G.Henri17,G.Hermann1,J.A.Hinton1,14,,A.Hoffmann18, W. -
1 Peter Mclaughlin the Question of the Authenticity of the Mechanical
Draft: occasionally updated Peter McLaughlin The Question of the Authenticity of the Mechanical Problems Sept. 30, 2013 Until the nineteenth century there was little doubt among scholars as to the authenticity of the Aristotelian Mechanical Problems. There were some doubters among the Renaissance humanists, but theirs were general doubts about the authenticity of a large class of writings, 1 not doubts based on the individual characteristics of this particular work. Some Humanists distrusted any text that hadn’t been passed by the Arabs to the Latin West in the High Middle Ages. However, by the end of the 18th century after Euler and Lagrange, the Mechanical Problems had ceased to be read as part of science and had become the object of history of science; and there the reading of the text becomes quite different from the Renaissance 2 readings. In his Histoire des mathématiques J.E. Montucla (1797) dismisses the Mechanical Problems with such epithets as “entirely false,” “completely ridiculous,” and “puerile.” William Whewell remarks in the History of the Inductive Sciences3 that “in scarcely any one instance are the answers, which Aristotle gives to his questions, of any value.” Neither of them, however, cast doubt on the authenticity of the work. Abraham Kaestner’s Geschichte der Mathematik (1796–1800) mentions doubts – but does not share them.4 Serious doubts about the authenticity of the Mechanical Problems as an individual work seem to be more a consequence of the disciplinary constitution of classical philology, particularly in nineteenth-century Germany. Some time between about 1830 and 1870, the opinion of most philologists shifted from acceptance to denial of the authenticity of the 5 Mechanical Problems. -
Gerard Lemson Alex Szalay, Mike Rippin DIBBS/Sciserver Collaborative Data-Driven Science
Collaborative data-driven science Gerard Lemson Alex Szalay, Mike Rippin DIBBS/SciServer Collaborative data-driven science } Started with the SDSS SkyServer } Built in a few months in 2001 } Goal: instant access to rich content } Idea: bring the analysis to the data } Interac@ve access at the core } Much of the scien@fic process is about data ◦ Data collec@on, data cleaning, data archiving, data organizaon, data publishing, mirroring, data distribu@on, data analy@cs, data curaon… 2 Collaborative data-driven science Form Based Queries 3 Collaborative data-driven science Image Access Collaborative data-driven science Custom SQL Collaborative data-driven science Batch Queries, MyDB Collaborative data-driven science Cosmological Simulations Collaborative data-driven science Turbulence Database Collaborative data-driven science Web Service Access through Python Collaborative data-driven science } Interac@ve science on petascale data } Sustain and enhance our astronomy effort } Create scalable open numerical laboratories } Scale system to many petabytes } Deep integraon with the “Long Tail” } Large footprint across many disciplines ◦ Also: Genomics, Oceanography, Materials Science } Use commonly shared building blocks } Major naonal and internaonal impact 10 Collaborative data-driven science } Offer more compung resources server side } Augment and combine SQL queries with easy- to-use scrip@ng tools } Heavy use of virtual machines } Interac@ve portal via iPython/Matlab/R } Batch jobs } Enhanced visualizaon tools 11 Collaborative data-driven science