Physics in the Cern Theory Division
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Faceting Space(Time): Regge's View of Geometry
Faceting space(time): Regge’s view of geometry Annalisa Marzuoli, Dipartimento di Matematica, Pavia University Curved surfaces as ‘simple’ models of curved spacetimes in Einstein’s General Relativity (Gauss geometries) The curvature of a generic smooth surface is perceived through its embedding into the 3D Euclidean space Looking at different regions three types of Gauss model geometries can be recognized The saddle surface (negative Gauss curvature) The surface of a sphere The Euclidean plane (positive Gauss is flat, i.e. its curvature) curvature is zero Principal curvatures are defined through ‘extrinsic properties’ of the surface, which is bent as seen in the ambient 3D space Glimpse definition In every point consider the tangent plane and the normal vector to the surface. (Any pair of) normal planes intersect the surface in curved lines. By resorting to the notion of osculating circle, the curvature of these embedded curves is evaluated (in the point). CASES: • > 0 and equal to 1/r • < 0 and equal to -1/r • = 0 r: radius of the osculating circle (Th.) There are only two distinct and mutually ortogonal principal directions in each point of an embedded surface, or: every direction is principal Principal Saddle surface: the principal curvatures curvatures have opposite sign (modulus) K1 = + 1/r1 K2 = - 1/r2 K1 = 1/r1 Sphere of radius r: K2 = 1/r2 K1 = K2 = 1/r > 0 (r1, r2 :radii of the All principal osculating circles) curvatures are equal in each Plane: limiting case point of the sphere r → ∞ (K1 = K2 = 0) Gauss curvature & the theorema -
April Meeting Goes Mile-High in 2004 Highlights New Techniques For
January 2004 Volume 13, No. 1 NEWS http://www.physics2005.org A Publication of The American Physical Society http://www.aps.org/apsnews April Meeting Goes Junior Members Respond to Mile-High in 2004 APS Ethics Survey By Ernie Tretkoff The “Mile High” city of Denver, International Affairs, Colorado, will host as many as History of Physics, and Few physicists received for- to include not just research mis- 1500 physicists at the 2004 APS Graduate Student Af- mal ethics training as part of their conduct such as data fabrication, April meeting, to be held May 1-4 fairs; and the Topical education, though many are con- falsification, and plagiarism, but 2004. Groups on Few-Body cerned about professional ethics, also issues such as authorship, Attendees will be drawn from a Systems, Precision a study by the APS Ethics Task proper credit of previous work, wide range of research areas. APS Measurement and Force has found. and data handling and reporting. units represented at the meeting Fundamental Con- Photo Credit: The Denver Metro Convention and Visitors Bureau The task force report was sub- “This was an interesting and include the Divisions of Astrophys- stants, Gravitation, Denver has the 10th largest downtown in America. mitted to and accepted by the sobering project,” said task force ics, Nuclear Physics, Particles and Plasma Astrophysics, APS Council at its meeting in chair Frances Houle of the IBM Fields, Plasma Physics, and Com- and Hadronic Physics. approximately 45 invited sessions. November. Almaden Research Center in San putational Physics; the Forums on The scientific program will fea- There will also be numerous con- The task force, which was con- Jose. -
Regge Finite Elements with Applications in Solid Mechanics and Relativity
Regge Finite Elements with Applications in Solid Mechanics and Relativity A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Lizao Li IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy Advisor: Prof. Douglas N. Arnold May 2018 © Lizao Li 2018 ALL RIGHTS RESERVED Acknowledgements I would like to express my sincere gratitude to my advisor Prof. Douglas Arnold, who taught me how to be a mathematician: diligence in thought and clarity in communication (I am still struggling with both). I am also grateful for his continuous guidance, help, support, and encouragement throughout my graduate study and the writing of this thesis. i Abstract This thesis proposes a new family of finite elements, called generalized Regge finite el- ements, for discretizing symmetric matrix-valued functions and symmetric 2-tensor fields. We demonstrate its effectiveness for applications in computational geometry, mathemati- cal physics, and solid mechanics. Generalized Regge finite elements are inspired by Tullio Regge’s pioneering work on discretizing Einstein’s theory of general relativity. We analyze why current discretization schemes based on Regge’s original ideas fail and point out new directions which combine Regge’s geometric insight with the successful framework of finite element analysis. In particular, we derive well-posed linear model problems from general relativity and propose discretizations based on generalized Regge finite elements. While the first part of the thesis generalizes Regge’s initial proposal and enlarges its scope to many other applications outside relativity, the second part of this thesis represents the initial steps towards a stable structure-preserving discretization of the Einstein’s field equation. -
Professor Helen Quinn
Professor Helen Quinn Helen Quinn was born in Australia and grew up in the Melbourne suburbs of Blackburn and Mitcham. She attended Tintern Girls Grammar School in Ringwood East. She matriculated successfully and obtained a cadetship from the Australian Department of Meteorology to fund her studies at the University of Melbourne. After beginning her undergraduate studies at the University, her family migrated to San Francisco in the early 1960s. Professor Quinn finished her undergraduate, and eventually graduate education at Stanford University. After receiving her doctorate from Stanford in 1967, she held a postdoctoral position at Deutsches Elektronen Synchrotron in Hamburg, Germany, then served as a research fellow at Harvard in 1971, joining the faculty there in 1972. She returned to Stanford in 1976 as a visitor on a Sloan Fellowship and joined the staff at the Stanford Linear Accelerator Centre (SLAC) in 1977. In her current position as a theoretical physicist at the Stanford Linear Accelerator Center (SLAC), Professor Quinn has made important contributions towards unifying the strong, weak and electromagnetic interactions into a single coherent model of particle physics. In 2000 she was awarded the Dirac Medal and Prize for pioneering contributions to the quest for a unified theory of quarks and leptons and of the strong, weak, and electromagnetic interactions. The award, shared with Professors Howard Georgi of Harvard and Jogesh Pati of the University of Maryland, recognized Professor Quinn for her work on the unification of the three interactions, and for fundamental insights about charge-parity conservation. She has also recently developed basic analysis methods used to search for the origin of particle-antiparticle asymmetry in nature. -
Highlights Se- Mathematics and Engineering— the Lead Signers of the Letter Exhibit
June 2003 NEWS Volume 12, No.6 A Publication of The American Physical Society http://www.aps.org/apsnews Nobel Laureates, Industry Leaders Petition April Meeting Prizes & Awards President to Boost Science and Technology Prizes and Awards were presented to seven- Sixteen Nobel Laureates in that “unless remedied, will affect call for “a Presidential initiative for teen recipients at the Physics and sixteen industry lead- our scientific and technological FY 2005, following on from your April meeting in Philadel- ers have written to President leadership, thereby affecting our budget of FY 2004, and focusing phia. George W. Bush to urge increas- economy and national security.” on the long-term research portfo- After the ceremony, ing funding for physical sciences, The letter, which is dated April lios of DOE, NASA, and the recipients and their environmental sciences, math- 14th, also indicates that “the Department of Commerce, in ad- guests gathered at the ematics, computer science and growth in expert personnel dition to NSF and NIH,” that, Franklin Institute for a engineering. abroad, combined with the di- “would turn around a decade-long special reception. The letter, reinforcing a recent minishing numbers of Americans decline that endangers the future Photo Credit: Stacy Edmonds of Edmonds Photography Council of Advisors on Science and entering the physical sciences, of our nation.” The top photo shows four of the five women recipients in front of a space-suit Technology report, highlights se- mathematics and engineering— The lead signers of the letter exhibit. They are (l to r): Geralyn “Sam” Zeller (Tanaka Award); Chung-Pei rious funding problems in the an unhealthy trend—is leading were Burton Richter, director Michele Ma (Maria-Goeppert Mayer Award); Yvonne Choquet-Bruhat physical sciences and related fields corporations to locate more of emeritus of SLAC, and Craig (Heineman Prize); and Helen Edwards (Wilson Prize). -
Questions in Quantum Physics: a Personal View
Questions in quantum physics: a personal view Rudolf Haag Waldschmidtstraße 4b, D–83727 Schliersee-Neuhaus, Germany Abstract An assessment of the present status of the theory, some immediate tasks which are suggested thereby and some questions whose answers may require a longer breath since they relate to significant changes in the conceptual and mathematical structure of the theory. 1 Introduction Personal views are shaped by past experiences and so it may be worth while pondering a little about accidental circumstances which channelled the course of one’s own thinking. Meeting the right person at the right time, stumbling across a book or article which suddenly opens a new window. Fifty years ago, as eager students at Munich University just entering the phase of our own scientific research, we were studying the enormous papers by Julian Schwinger on Quantum Electrodynamics, following the arguments line by line but not really grasping the message. I remember the feelings of frustration, realizing that we were far away from the centers of action. But, mixed with this, also some dismay which did not only refer to the enormous arsenal of formalism in the new arXiv:hep-th/0001006v1 3 Jan 2000 developments of QED but began with the standard presentation of the interpretation of Quantum Theory. I remember long discussions with my thesis advisor Fritz Bopp, often while circling some blocks of streets ten times late in the evening, where we looked in vain for some reality behind the enigma of wave-particle dualism. Why should physical quantities correspond to operators in Hilbert space? Why should probabilities be described as absolute squares of amplitudes?, etc., etc. -
From Algebraic Quantum Field Theory to Effective Quantum Gravity
Algebraic approach to QFT Quantum gravity Locality and beyond: from algebraic quantum field theory to effective quantum gravity Kasia Rejzner University of York Local Quantum Physics and beyond in memoriam Rudolf Haag, 26.09.2016 Kasia Rejzner Locality and beyond 1 / 26 Algebraic approach to QFT Quantum gravity Outline of the talk 1 Algebraic approach to QFT AQFT LCQFT pAQFT 2 Quantum gravity Effective quantum gravity Observables The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). Kasia Rejzner Locality and beyond 2 / 26 One of the fathers of LQP. We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. Kasia Rejzner Locality and beyond 2 / 26 We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. Kasia Rejzner Locality and beyond 2 / 26 AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. We will all miss him. Kasia Rejzner Locality and beyond 2 / 26 It started as the axiomatic framework of Haag-Kastler[ Haag & Kastler 64]: a model is defined by associating to each region O of Minkowski spacetime the algebra A(O) of observables that can be measured in O. -
July 2007 (Volume 16, Number 7) Entire Issue
July 2007 Volume 16, No. 7 www.aps.org/publications/apsnews APS NEWS Election Preview A PUBLICATION OF THE AMERICAN PHYSICAL SOCIETY • WWW.apS.ORG/PUBLICATIONS/apSNEWS Pages 6-7 Executive Board Resolution Thanks US physics team trains for competition in Iran By Katherine McAlpine Legislators for Support of Science Twenty-four high school stu- The APS Executive Board bill authorizes nearly $60 billion dents comprising the US Phys- has passed a resolution thanking for various programs for FY 2008 ics Olympiad team vied for five House and Senate policy makers through FY 2011. The bill would places on the traveling team at for recently-passed legislation double the NSF budget over five the University of Maryland from that strengthens the science, math years and double the DOE Office May 22nd to June 1st. Those and engineering activities of our of Science budget over 10 years. chosen to travel will compete nation. The House of Representatives this month against teams from “Sustaining and improving the passed five separate authorization all over the world at Isfahan standard of living of American bills, which were then combined University of Technology in Is- citizens, achieving energy security into one bill, H.R. 2272, the 21st fahan, Iran. and environmental sustainability, Century Competitiveness Act of Over 3,100 US Physics Team providing the jobs of tomorrow 2007. The bill would put the NSF hopefuls took the preliminary and defending our nation against budget and the NIST Scientific examination in January, and 200 aggressors all require federal in- and Technical Research and Ser- were given a second exam in vestments in science education vices budget on track to double in March to determine the top 24 and research… The Board con- 10 years. -
The Making of the Standard Theory
August 11, 2016 9:28 The Standard Theory of Particle Physics - 9.61in x 6.69in b2471-ch02 page 29 Chapter 2 The Making of the Standard Theory John Iliopoulos Laboratoire de Physique Th´eorique, Ecole´ Normale Sup´erieure, 24 rue Lhomond, 75005 Paris, France 1. Introduction The construction of the Standard Model, which became gradually the Standard Theory of elementary particle physics, is, probably, the most remarkable achieve- ment of modern theoretical physics. In this Chapter we shall deal mostly with the weak interactions. It may sound strange that a revolution in particle physics was initiated by the study of the weakest among them (the effects of the gravitational interactions are not measurable in high energy physics), but we shall see that the weak interactions triggered many such revolutions and we shall have the occasion to meditate on the fundamental significance of “tiny” effects. We shall outline the various steps, from the early days of the Fermi theory to the recent experimental discoveries, which confirmed all the fundamental predictions of the Theory. We shall follow a phenomenological approach, in which the introduction of every new concept is motivated by the search of a consistent theory which agrees with experiment. As we shall explain, this is only part of the story, the other part being the requirement of mathematical consistency. Both went in parallel and the real history requires the understanding of both. In fact, as we intend to show, the initial motivation was not really phenomenological. It is one of these rare cases in which a revolution in physics came from theorists trying to go beyond a simple phenomenological model, The Standard Theory of Particle Physics Downloaded from www.worldscientific.com not from an experimental result which forced them to do so. -
Scaling Laws in Particle Physics and Astrophysics
SCALING LAWS IN PARTICLE PHYSICS AND ASTROPHYSICS RUDOLF MURADYAN Dedicated to the Golden Jubilee (1961-2011) of publication of the article by Geoffrey Chew and Steven Frautschi in Phys. Rev. Lett. 7, 394, 1961, where a celebrated scaling law J m2 has been conjectured for spin/mass dependence of hadrons. G. Chew S. Frautschi 1. INTRODUCTION: WHAT IS SCALING? Any polynomial power law f() x c xn , where constant c has a dimension dim f dimc (dimx )n exhibits the property of scaling or scale invariance. Usually n is called scaling exponent. The word scaling express the fact that function f is shape-invariant with respect to the dilatation transformation x x f ( x) c ( x)n n f() x and this transformation preserves the shape of function f . We say, following Leonhard Euler, that f is homogeneous of degree “n” if for any value of parameter f ( x) n f() x . Differentiating this relation with respect to and putting 1we obtain simple differential equation x f() x n f() x solution of which brings back to the polynomial power scaling law. There are tremendously many different scaling laws in Nature. The most important of them can be revealed by Google search of scaling site:nobelprize.org in the official site of Nobel Foundation, where nearly 100 results appears. Ten of them are shown below: 1. Jerome I. Friedman - Nobel Lecture 2. Daniel C. Tsui - Nobel Lecture 3. Gerardus 't Hooft - Nobel Lecture 4. Henry W. Kendall - Nobel Lecture 5. Pierre-Gilles de Gennes - Nobel Lecture 6. Jack Steinberger - Nobel Lecture 7. -
Courier Volume 45 Number 6 July/August 2005
INTERNATIONACERL JOURNAL OF HIGH-ENERGNY PHYSIC S COURIER VOLUME 45 NUMBER 6 JULY/AUGUST 2005 LABORATORIES FREDHOYLE LAKE BAIKAL SLAC reorganizes The life of a pioneer in The next step towards forthe future p6 nuclear astrophysics pl5 higher energies p24 Linde Kryotechnik AG & Linde BOC Process Plants LLC 4.5K Helium Coldbox for the Spallation Neutron Source at ORNL Coldbox in final stage of fabrication at the Linde shop in Coldbox ready to load on special the Port of Catoosa, Oklahoma, USA low clearance trailer Coldbox in operation at the SNS Central Helium Liquefier Linde KyotechnikAG Phone:+41 (0)52 304 05 55 Linde BOC Process Plants LLC Phone:+1 918 250 8522 DaettlikonerstrasseS Fax: +41 (0)52 304 05 50 Cryogenic Plants and Services Fax: +1 918 250 6915 CH-8422 Pfungen Email: [email protected] 3522 East 61st Street [email protected] Switzerland www.linde-kryotechmk.ch Tulsa, OK 74133-1923/USA www.lindebocpp.com X-ftaqr Oefecfor Digital Puke Processor XR-tOOCR at 149 eV FWHM Resolution No Liquid Nitrogen PX4 Solid State Design Digital Pulse Processor Power Supply Easy to Use Shaping Amplifier Low Cost MCA Features APPLICATIONS • Trapezoidal shaping to reduce • Nuclear Physics ballistic deficit • Synchroton Radiation • Wide range of shaping time settings • High Energy Physics • High count rate capability • Neutron Experiments • High throughput • Astrophysics • MCA with 8 k channels • Research & Teaching • High energy resolution • Nuclear Medicine • Excellent pile-up rejection • X-Ray Fluorescence • Enhanced stability • USB interface XR100CR X~Ray Detector XR100CR fitted for vacuum • Software instrument control, data with P;X4 Digital Pulse applications Visit Us Now Processor, Power Supply, www.amptek.com acquisition and analysis Shaping Amplifier & MCA • Oscilloscope mode available AMPTEK Inc. -
David Olive: His Life and Work
David Olive his life and work Edward Corrigan Department of Mathematics, University of York, YO10 5DD, UK Peter Goddard Institute for Advanced Study, Princeton, NJ 08540, USA St John's College, Cambridge, CB2 1TP, UK Abstract David Olive, who died in Barton, Cambridgeshire, on 7 November 2012, aged 75, was a theoretical physicist who made seminal contributions to the development of string theory and to our understanding of the structure of quantum field theory. In early work on S-matrix theory, he helped to provide the conceptual framework within which string theory was initially formulated. His work, with Gliozzi and Scherk, on supersymmetry in string theory made possible the whole idea of superstrings, now understood as the natural framework for string theory. Olive's pioneering insights about the duality between electric and magnetic objects in gauge theories were way ahead of their time; it took two decades before his bold and courageous duality conjectures began to be understood. Although somewhat quiet and reserved, he took delight in the company of others, generously sharing his emerging understanding of new ideas with students and colleagues. He was widely influential, not only through the depth and vision of his original work, but also because the clarity, simplicity and elegance of his expositions of new and difficult ideas and theories provided routes into emerging areas of research, both for students and for the theoretical physics community more generally. arXiv:2009.05849v1 [physics.hist-ph] 12 Sep 2020 [A version of section I Biography is to be published in the Biographical Memoirs of Fellows of the Royal Society.] I Biography Childhood David Olive was born on 16 April, 1937, somewhat prematurely, in a nursing home in Staines, near the family home in Scotts Avenue, Sunbury-on-Thames, Surrey.