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Francis E. Low
NATIONAL ACADEMY OF SCIENCES F R A N C I S E . L OW 1 9 2 1 – 2 0 0 7 A Biographical Memoir by DAVID KAISER AND MARC A . K A S T N E R Any opinions expressed in this memoir are those of the authors and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2010 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. Courtesy of MIT Archives. FRANCIS E. LOW October 27, 1921–February 16, 2007 BY DAVID KAISER AND MARC A . K ASTNER RANCIS E. LOW, A MEMBER OF THE NATIONAL ACADEMY OF SCIENCES Fsince 1967, died on February 16, 2007, in Haverford, Pennsylvania. His career exemplified the maturing of theo- retical physics in the United States during the years after World War II. Low also experienced some of the new roles for physicists, from organized political engagement and consulting on national security issues to high-level university administration. One of Low’s landmark articles helped to lay the groundwork for the renormalization-group approach in quantum field theory, a seminal technique in condensed- matter and particle physics. He also contributed influential approximation techniques for treating particle scattering. EARLY YEARS Low was an only child, who lived near Washington Square Park in Greenwich Village. His mother’s parents were physi- cians and socialists. In fact, his grandfather helped found the Socialist Party of America. His mother also became a doctor. She made house calls at night in Greenwich Village until she turned 80, treating patients such as anthropolo- gist Margaret Mead. -
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. -
Scientific and Related Works of Chen Ning Yang
Scientific and Related Works of Chen Ning Yang [42a] C. N. Yang. Group Theory and the Vibration of Polyatomic Molecules. B.Sc. thesis, National Southwest Associated University (1942). [44a] C. N. Yang. On the Uniqueness of Young's Differentials. Bull. Amer. Math. Soc. 50, 373 (1944). [44b] C. N. Yang. Variation of Interaction Energy with Change of Lattice Constants and Change of Degree of Order. Chinese J. of Phys. 5, 138 (1944). [44c] C. N. Yang. Investigations in the Statistical Theory of Superlattices. M.Sc. thesis, National Tsing Hua University (1944). [45a] C. N. Yang. A Generalization of the Quasi-Chemical Method in the Statistical Theory of Superlattices. J. Chem. Phys. 13, 66 (1945). [45b] C. N. Yang. The Critical Temperature and Discontinuity of Specific Heat of a Superlattice. Chinese J. Phys. 6, 59 (1945). [46a] James Alexander, Geoffrey Chew, Walter Salove, Chen Yang. Translation of the 1933 Pauli article in Handbuch der Physik, volume 14, Part II; Chapter 2, Section B. [47a] C. N. Yang. On Quantized Space-Time. Phys. Rev. 72, 874 (1947). [47b] C. N. Yang and Y. Y. Li. General Theory of the Quasi-Chemical Method in the Statistical Theory of Superlattices. Chinese J. Phys. 7, 59 (1947). [48a] C. N. Yang. On the Angular Distribution in Nuclear Reactions and Coincidence Measurements. Phys. Rev. 74, 764 (1948). 2 [48b] S. K. Allison, H. V. Argo, W. R. Arnold, L. del Rosario, H. A. Wilcox and C. N. Yang. Measurement of Short Range Nuclear Recoils from Disintegrations of the Light Elements. Phys. Rev. 74, 1233 (1948). [48c] C. -
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. -
The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven Versus Exploratory Experiments in the History of High-Energy Particle Physics
[Accepted for Publication in Science in Context] The Strong and Weak Senses of Theory-Ladenness of Experimentation: Theory-Driven versus Exploratory Experiments in the History of High-Energy Particle Physics Koray Karaca University of Wuppertal Interdisciplinary Centre for Science and Technology Studies (IZWT) University of Wuppertal Gaußstr. 20 42119 Wuppertal, Germany [email protected] Argument In the theory-dominated view of scientific experimentation, all relations of theory and experiment are taken on a par; namely, that experiments are performed solely to ascertain the conclusions of scientific theories. As a result, different aspects of experimentation and of the relation of theory to experiment remain undifferentiated. This in turn fosters a notion of theory- ladenness of experimentation (TLE) that is too coarse-grained to accurately describe the relations of theory and experiment in scientific practice. By contrast, in this article, I suggest that TLE should be understood as an umbrella concept that has different senses. To this end, I introduce a three-fold distinction among the theories of high-energy particle physics (HEP) as background theories, model theories and phenomenological models. Drawing on this categorization, I contrast two types of experimentation, namely, “theory-driven” and “exploratory” experiments, and I distinguish between the “weak” and “strong” senses of TLE in the context of scattering experiments from the history of HEP. This distinction enables to identify the exploratory character of the deep-inelastic electron-proton scattering experiments— performed at the Stanford Linear Accelerator Center (SLAC) between the years 1967 and 1973—thereby shedding light on a crucial phase of the history of HEP, namely, the discovery of “scaling”, which was the decisive step towards the construction of quantum chromo-dynamics (QCD) as a gauge theory of strong interactions. -
Verlinde's Emergent Gravity and Whitehead's Actual Entities
The Founding of an Event-Ontology: Verlinde's Emergent Gravity and Whitehead's Actual Entities by Jesse Sterling Bettinger A Dissertation submitted to the Faculty of Claremont Graduate University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate Faculty of Religion and Economics Claremont, California 2015 Approved by: ____________________________ ____________________________ © Copyright by Jesse S. Bettinger 2015 All Rights Reserved Abstract of the Dissertation The Founding of an Event-Ontology: Verlinde's Emergent Gravity and Whitehead's Actual Entities by Jesse Sterling Bettinger Claremont Graduate University: 2015 Whitehead’s 1929 categoreal framework of actual entities (AE’s) are hypothesized to provide an accurate foundation for a revised theory of gravity to arise compatible with Verlinde’s 2010 emergent gravity (EG) model, not as a fundamental force, but as the result of an entropic force. By the end of this study we should be in position to claim that the EG effect can in fact be seen as an integral sub-sequence of the AE process. To substantiate this claim, this study elaborates the conceptual architecture driving Verlinde’s emergent gravity hypothesis in concert with the corresponding structural dynamics of Whitehead’s philosophical/scientific logic comprising actual entities. This proceeds to the extent that both are shown to mutually integrate under the event-based covering logic of a generative process underwriting experience and physical ontology. In comparing the components of both frameworks across the epistemic modalities of pure philosophy, string theory, and cosmology/relativity physics, this study utilizes a geomodal convention as a pre-linguistic, neutral observation language—like an augur between the two theories—wherein a visual event-logic is progressively enunciated in concert with the specific details of both models, leading to a cross-pollinized language of concepts shown to mutually inform each other. -
The Early Years of String Theory: a Personal Perspective
CALT-68-2657 THE EARLY YEARS OF STRING THEORY: A PERSONAL PERSPECTIVE John H. Schwarz California Institute of Technology Pasadena, CA 91125, USA Abstract arXiv:0708.1917v3 [hep-th] 3 Apr 2009 This article surveys some of the highlights in the development of string theory through the first superstring revolution in 1984. The emphasis is on topics in which the author was involved, especially the observation that critical string theories provide consistent quantum theories of gravity and the proposal to use string theory to construct a unified theory of all fundamental particles and forces. Based on a lecture presented on June 20, 2007 at the Galileo Galilei Institute 1 Introduction I am happy to have this opportunity to reminisce about the origins and development of string theory from 1962 (when I entered graduate school) through the first superstring revolution in 1984. Some of the topics were discussed previously in three papers that were written for various special events in 2000 [1, 2, 3]. Also, some of this material was reviewed in the 1985 reprint volumes [4], as well as the string theory textbooks [5, 6]. In presenting my experiences and impressions of this period, it is inevitable that my own contributions are emphasized. Some of the other early contributors to string theory have presented their recollections at the Galileo Galilei Institute meeting on “The Birth of String Theory” in May 2007. Since I was unable to attend that meeting, my talk was given at the GGI one month later. Taken together, the papers in this collection should -
Memories of Julian Schwinger
Memories of Julian Schwinger Edward Gerjuoy* ABSTRACT The career and accomplishments of Julian Schwinger, who shared the Nobel Prize for physics in 1965, have been reviewed in numerous books and articles. For this reason these Memories, which seek to convey a sense of Schwinger’s remarkable talents as a physicist, concentrate primarily (though not entirely) on heretofore unpuBlished pertinent recollections of the youthful Schwinger by this writer, who first encountered Schwinger in 1934 when they both were undergraduates at the City College of New York. *University of Pittsburgh Dept. of Physics and Astronomy, Pittsburgh, PA 15260. 1 Memories of Julian Schwinger Julian Seymour Schwinger, who shared the 1965 Nobel prize in physics with Richard Feynman and Sin-itiro Tomonaga, died in Los Angeles on July 16, 1994 at the age of 76. He was a remarkably talented theoretical physicist, who—through his own publications and through the students he trained—had an enormous influence on the evolution of physics after World War II. Accordingly, his life and work have been reviewed in a number of publications [1-3, inter alia]. There also have been numerous published obituaries, of course [4-5, e.g.] These Memories largely are the text of the Schwinger portion of a colloquium talk, “Recollections of Oppenheimer and Schwinger”, which the writer has given at a number of universities, and which can be found on the web [6]. The portion of the talk devoted to J. Robert Oppenheimer—who is enduringly famous as director of the Los Alamos laboratory during World War II—has been published [7], but the portion devoted to Julian is essentially unpublished; references 7-9 describe the basically trivial exceptions to this last assertion. -
Center for History of Physics Newsletter, Spring 2008
One Physics Ellipse, College Park, MD 20740-3843, CENTER FOR HISTORY OF PHYSICS NIELS BOHR LIBRARY & ARCHIVES Tel. 301-209-3165 Vol. XL, Number 1 Spring 2008 AAS Working Group Acts to Preserve Astronomical Heritage By Stephen McCluskey mong the physical sciences, astronomy has a long tradition A of constructing centers of teaching and research–in a word, observatories. The heritage of these centers survives in their physical structures and instruments; in the scientific data recorded in their observing logs, photographic plates, and instrumental records of various kinds; and more commonly in the published and unpublished records of astronomers and of the observatories at which they worked. These records have continuing value for both historical and scientific research. In January 2007 the American Astronomical Society (AAS) formed a working group to develop and disseminate procedures, criteria, and priorities for identifying, designating, and preserving structures, instruments, and records so that they will continue to be available for astronomical and historical research, for the teaching of astronomy, and for outreach to the general public. The scope of this charge is quite broad, encompassing astronomical structures ranging from archaeoastronomical sites to modern observatories; papers of individual astronomers, observatories and professional journals; observing records; and astronomical instruments themselves. Reflecting this wide scope, the members of the working group include historians of astronomy, practicing astronomers and observatory directors, and specialists Oak Ridge National Laboratory; Santa encounters tight security during in astronomical instruments, archives, and archaeology. a wartime visit to Oak Ridge. Many more images recently donated by the Digital Photo Archive, Department of Energy appear on page 13 and The first item on the working group’s agenda was to determine through out this newsletter. -
A Festschrift for Thomas Erber
Physics:Doing A Festschrift For Thomas Erber Edited by Porter Wear Johnson GC(2251)_PhysicsBookCvr10.indd 1 9/15/10 10:33 AM Doing Physics: A Festschrift for Tom Erber Edited by Porter Wear Johnson Illinois Institute of Technology IIT Press Doing Physics: A Festschrift For Thomas Erber edited by Porter Wear Johnson Published by: IIT Press 3300 S. Federal St., 301MB Chicago, IL 60616 Copyright °c 2010 IIT Press All rights reserved. No part of this book, including interior design, cover design, and icons, may be reproduced or transmitted in any form, by any means (electronic, photo- copying, recording, or otherwise) without the prior written permission of the publisher. ISBN: 1-61597-000-2 Series Editor: Technical Editor: Sudhakar Nair Julia Chase Editorial Board David Arditi Roya Ayman Krishna Erramilli Porter Wear Johnson Harry Francis Mallgrave Mickie Piatt Katherine Riley Keiicho Sato Vincent Turitto Geo®rey Williamson Doing Physics: A Festschrift for Tom Erber Preface \Au¼ertenÄ wir oben, da¼ die Geschichte des Menschen den Menschen darstelle, so lÄa¼tsich hier auch wohl behaupten, da¼ die Geschichte der Wissenschaft die Wissenschaft selbst sei." Goethe, Zur Farbenlehre: Vorwort (1808) It is widely asserted that the great physicists who grasped the full unity of physics are all dead, having been replaced in this age of specialization by sci- entists who have a deep understanding only for issues of rather limited scope. Indeed, it is di±cult to refute such a viewpoint today, at the end of the ¯rst decade of the twenty-¯rst century. The unifying principles of the quantum the- ory and relativity are part of the ethos of physics, but fragmented development in various disjointed areas has characterized the past several decades of progress. -
The Guiding Influence of Stanley Mandelstam, from S-Matrix Theory
The Guiding Influence of Stanley Mandelstam, from S-Matrix Theory to String Theory Peter Goddard School of Natural Sciences Institute for Advanced Study Princeton, NJ 08540, USA Abstract The guiding influence of some of Stanley Mandelstam’s key contributions to the development of theoretical high energy physics is discussed, from the motivation for the study of the analytic properties of the scattering matrix through to dual resonance models and their evolution into string theory. arXiv:1702.05986v1 [physics.hist-ph] 20 Feb 2017 a contribution to Memorial Volume for Stanley Mandelstam, ed. N. Berkovits et al. (World Scientific, Singapore, 2017) 1 The Mandelstam Representation When I began research on the theory of the strong interactions in Cambridge in 1967, the focuses of study were the Regge theory of the high energy behavior of scattering ampli- tudes, and the properties of these amplitudes as analytic functions of complex variables. Most prominent amongst the names conjured with in these subjects was that of Stanley Mandelstam: the complex variables that the scattering amplitudes depended on were the Mandelstam variables; the complex space they varied over was the Mandelstam diagram; and the proposal of the Mandelstam representation had provided the inspiration for much of the study of the analytic properties of scattering amplitudes that was then in full spate. Entering the field then, one was not readily conscious of the fact that this conceptual frame- work had its origins less than ten years earlier, in 1958–59, in a seminal series of papers [1–3] by Mandelstam. The book, The Analytic S-Matrix, by Eden, Landshoff, Olive and Polk- inghorne [4], published in 1966, the bible for research students in Cambridge at the time, begins with the slightly arch sentence, “One of the most important discoveries in elementary particle physics has been that of the complex plane”. -
Research Biography
After graduating from Oxford in 1964, I joined the research group of Luis Alvarez at the University of California, Berkeley, where I obtained a Ph.D. in experimental particle physics in 1969. That was a time of great excitement, with discoveries coming thick and fast. I studied the new phenomenon of CP (charge-conjugation times parity) violation in neutral K mesons, using the bubble-chamber technique for which Alvarez was awarded the 1968 Nobel Prize. In those days it was possible to do front- line particle physics in a small team at a local accelerator — in this case with just three collaborators, using the Bevatron at the Lawrence Radiation Laboratory (later renamed the Lawrence Berkeley Laboratory, LBL, to get rid of the dreaded R word). However, it was already clear then that the era of bubble chambers was coming to an end and the future lay with big collaborations using electronic detectors, for which I had little enthusiasm. In any case my aptitude lay more on the theoretical and computational side, and I was fortunate to be offered a post-doctoral position in the LBL theory group. Sensational new results from the nearby Stanford Linear Accelerator Center were indicating that the proton was composed of point- like constituents, consistent with quarks, which had previously been held to be a mathematical fiction. My first theoretical project was to show that meson scattering could be explained in a self-consistent way without invoking constituents (the so-called bootstrap hypothesis). This was suggested by Geoffrey Chew, the charismatic head of the LBL theory group and a leading opponent of quarks.