Freeman Dyson
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Preliminary Acknowledgments
PRELIMINARY ACKNOWLEDGMENTS The central thesis of I Am You—that we are all the same person—is apt to strike many readers as obviously false or even absurd. How could you be me and Hitler and Gandhi and Jesus and Buddha and Greta Garbo and everybody else in the past, present and future? In this book I explain how this is possible. Moreover, I show that this is the best explanation of who we are for a variety of reasons, not the least of which is that it provides the metaphysical foundations for global ethics. Variations on this theme have been voiced periodically throughout the ages, from the Upanishads in the Far East, Averroës in the Middle East, down to Josiah Royce in the North East (and West). More recently, a number of prominent 20th century physicists held this view, among them Erwin Schrödinger, to whom it came late, Fred Hoyle, who arrived at it in middle life, and Freeman Dyson, to whom it came very early as it did to me. In my youth I had two different types of experiences, both of which led to the same inexorable conclusion. Since, in hindsight, I would now classify one of them as “mystical,” I will here speak only of the other—which is so similar to the experience Freeman Dyson describes that I have conveniently decided to let the physicist describe it for “both” of “us”: Enlightenment came to me suddenly and unexpectedly one afternoon in March when I was walking up to the school notice board to see whether my name was on the list for tomorrow’s football game. -
Computer Oral History Collection, 1969-1973, 1977
Computer Oral History Collection, 1969-1973, 1977 INTERVIEWEES: John Todd & Olga Taussky Todd INTERVIEWER: Henry S. Tropp DATE OF INTERVIEW: July 12, 1973 Tropp: This is a discussion with Doctor and Mrs. Todd in their apartment at the University of Michigan on July 2nd, l973. This question that I asked you earlier, Mrs. Todd, about your early meetings with Von Neumann, I think are just worth recording for when you first met him and when you first saw him. Olga Tauskky Todd: Well, I first met him and saw him at that time. I actually met him at that location, he was lecturing in the apartment of Menger to a private little set. Tropp: This was Karl Menger's apartment in Vienna? Olga Tauskky Todd: In Vienna, and he was on his honeymoon. And he lectured--I've forgotten what it was about, I am ashamed to say. It would come back, you know. It would come back, but I cannot recall it at this moment. It had nothing to do with game theory. I don't know, something in.... John Todd: She has a very good memory. It will come back. Tropp: Right. Approximately when was this? Before l930? Olga Tauskky Todd: For additional information, contact the Archives Center at 202.633.3270 or [email protected] Computer Oral History Collection, 1969-1973, 1977 No. I think it may have been in 1932 or something like that. Tropp: In '32. Then you said you saw him again at Goettingen, after the-- Olga Tauskky Todd: I saw him at Goettingen. -
Richard Phillips Feynman Physicist and Teacher Extraordinary
ARTICLE-IN-A-BOX Richard Phillips Feynman Physicist and Teacher Extraordinary The first three decades of the twentieth century have been among the most momentous in the history of physics. The first saw the appearance of special relativity and the birth of quantum theory; the second the creation of general relativity. And in the third, quantum mechanics proper was discovered. These developments shaped the progress of fundamental physics for the rest of the century and beyond. While the two relativity theories were largely the creation of Albert Einstein, the quantum revolution took much more time and involved about a dozen of the most creative minds of a couple of generations. Of all those who contributed to the consolidation and extension of the quantum ideas in later decades – now from the USA as much as from Europe and elsewhere – it is generally agreed that Richard Phillips Feynman was the most gifted, brilliant and intuitive genius out of many extremely gifted physicists. Here are descriptions of him by leading physicists of his own, and older as well as younger generations: “He is a second Dirac, only this time more human.” – Eugene Wigner …Feynman was not an ordinary genius but a magician, that is one “who does things that nobody else could ever do and that seem completely unexpected.” – Hans Bethe “… an honest man, the outstanding intuitionist of our age and a prime example of what may lie in store for anyone who dares to follow the beat of a different drum..” – Julian Schwinger “… the most original mind of his generation.” – Freeman Dyson Richard Feynman was born on 11 May 1918 in Far Rockaway near New York to Jewish parents Lucille Phillips and Melville Feynman. -
Disturbing the Memory
1 1 February 1984 DISTURBING THE MEMORY E. T. Jaynes, St. John's College, Cambridge CB2 1TP,U.K. This is a collection of some weird thoughts, inspired by reading "Disturbing the Universe" by Freeman Dyson 1979, which I found in a b o okstore in Cambridge. He reminisces ab out the history of theoretical physics in the p erio d 1946{1950, particularly interesting to me b ecause as a graduate student at just that time, I knew almost every p erson he mentions. From the rst part of Dyson's b o ok we can learn ab out some incidents of this imp ortant p erio d in the development of theoretical physics, in which the present writer happ ened to b e a close and interested onlo oker but, regrettably, not a participant. Dyson's account lled in several gaps in myown knowledge, and in so doing disturb ed my memory into realizing that I in turn maybein a p osition to ll in some gaps in Dyson's account. Perhaps it would have b een b etter had I merely added myown reminiscences to Dyson's and left it at that. But like Dyson in the last part of his b o ok, I found it more fun to build a structure of conjectures on the rather lo ose framework of facts at hand. So the following is o ered only as a conjecture ab out how things mighthave b een; i.e. it ts all the facts known to me, and seems highly plausible from some vague impressions that I have retained over the years. -
Council for Innovative Research Peer Review Research Publishing System
ISSN 2347-3487 Einstein's gravitation is Einstein-Grossmann's equations Alfonso Leon Guillen Gomez Independent scientific researcher, Bogota, Colombia E-mail: [email protected] Abstract While the philosophers of science discuss the General Relativity, the mathematical physicists do not question it. Therefore, there is a conflict. From the theoretical point view “the question of precisely what Einstein discovered remains unanswered, for we have no consensus over the exact nature of the theory's foundations. Is this the theory that extends the relativity of motion from inertial motion to accelerated motion, as Einstein contended? Or is it just a theory that treats gravitation geometrically in the spacetime setting?”. “The voices of dissent proclaim that Einstein was mistaken over the fundamental ideas of his own theory and that their basic principles are simply incompatible with this theory. Many newer texts make no mention of the principles Einstein listed as fundamental to his theory; they appear as neither axiom nor theorem. At best, they are recalled as ideas of purely historical importance in the theory's formation. The very name General Relativity is now routinely condemned as a misnomer and its use often zealously avoided in favour of, say, Einstein's theory of gravitation What has complicated an easy resolution of the debate are the alterations of Einstein's own position on the foundations of his theory”, (Norton, 1993) [1]. Of other hand from the mathematical point view the “General Relativity had been formulated as a messy set of partial differential equations in a single coordinate system. People were so pleased when they found a solution that they didn't care that it probably had no physical significance” (Hawking and Penrose, 1996) [2]. -
Arxiv:1601.07125V1 [Math.HO]
CHALLENGES TO SOME PHILOSOPHICAL CLAIMS ABOUT MATHEMATICS ELIAHU LEVY Abstract. In this note some philosophical thoughts and observations about mathematics are ex- pressed, arranged as challenges to some common claims. For many of the “claims” and ideas in the “challenges” see the sources listed in the references. .1. Claim. The Antinomies in Set Theory, such as the Russell Paradox, just show that people did not have a right concept about sets. Having the right concept, we get rid of any contradictions. Challenge. It seems that this cannot be honestly said, when often in “axiomatic” set theory the same reasoning that leads to the Antinomies (say to the Russell Paradox) is used to prove theorems – one does not get to the contradiction, but halts before the “catastrophe” to get a theorem. As if the reasoning that led to the Antinomies was not “illegitimate”, a result of misunderstanding, but we really have a contradiction (antinomy) which we, somewhat artificially, “cut”, by way of the axioms, to save our consistency. One may say that the phenomena described in the famous G¨odel’s Incompleteness Theorem are a reflection of the Antinomies and the resulting inevitability of an axiomatics not entirely parallel to intuition. Indeed, G¨odel’s theorem forces us to be presented with a statement (say, the consistency of Arithmetics or of Set Theory) which we know we cannot prove, while intuition puts a “proof” on the tip of our tongue, so to speak (that’s how we “know” that the statement is true!), but which our axiomatics, forced to deviate from intuition to be consistent, cannot recognize. -
K-Theory and Algebraic Geometry
http://dx.doi.org/10.1090/pspum/058.2 Recent Titles in This Series 58 Bill Jacob and Alex Rosenberg, editors, ^-theory and algebraic geometry: Connections with quadratic forms and division algebras (University of California, Santa Barbara) 57 Michael C. Cranston and Mark A. Pinsky, editors, Stochastic analysis (Cornell University, Ithaca) 56 William J. Haboush and Brian J. Parshall, editors, Algebraic groups and their generalizations (Pennsylvania State University, University Park, July 1991) 55 Uwe Jannsen, Steven L. Kleiman, and Jean-Pierre Serre, editors, Motives (University of Washington, Seattle, July/August 1991) 54 Robert Greene and S. T. Yau, editors, Differential geometry (University of California, Los Angeles, July 1990) 53 James A. Carlson, C. Herbert Clemens, and David R. Morrison, editors, Complex geometry and Lie theory (Sundance, Utah, May 1989) 52 Eric Bedford, John P. D'Angelo, Robert E. Greene, and Steven G. Krantz, editors, Several complex variables and complex geometry (University of California, Santa Cruz, July 1989) 51 William B. Arveson and Ronald G. Douglas, editors, Operator theory/operator algebras and applications (University of New Hampshire, July 1988) 50 James Glimm, John Impagliazzo, and Isadore Singer, editors, The legacy of John von Neumann (Hofstra University, Hempstead, New York, May/June 1988) 49 Robert C. Gunning and Leon Ehrenpreis, editors, Theta functions - Bowdoin 1987 (Bowdoin College, Brunswick, Maine, July 1987) 48 R. O. Wells, Jr., editor, The mathematical heritage of Hermann Weyl (Duke University, Durham, May 1987) 47 Paul Fong, editor, The Areata conference on representations of finite groups (Humboldt State University, Areata, California, July 1986) 46 Spencer J. Bloch, editor, Algebraic geometry - Bowdoin 1985 (Bowdoin College, Brunswick, Maine, July 1985) 45 Felix E. -
Advanced Information on the Nobel Prize in Physics, 5 October 2004
Advanced information on the Nobel Prize in Physics, 5 October 2004 Information Department, P.O. Box 50005, SE-104 05 Stockholm, Sweden Phone: +46 8 673 95 00, Fax: +46 8 15 56 70, E-mail: [email protected], Website: www.kva.se Asymptotic Freedom and Quantum ChromoDynamics: the Key to the Understanding of the Strong Nuclear Forces The Basic Forces in Nature We know of two fundamental forces on the macroscopic scale that we experience in daily life: the gravitational force that binds our solar system together and keeps us on earth, and the electromagnetic force between electrically charged objects. Both are mediated over a distance and the force is proportional to the inverse square of the distance between the objects. Isaac Newton described the gravitational force in his Principia in 1687, and in 1915 Albert Einstein (Nobel Prize, 1921 for the photoelectric effect) presented his General Theory of Relativity for the gravitational force, which generalized Newton’s theory. Einstein’s theory is perhaps the greatest achievement in the history of science and the most celebrated one. The laws for the electromagnetic force were formulated by James Clark Maxwell in 1873, also a great leap forward in human endeavour. With the advent of quantum mechanics in the first decades of the 20th century it was realized that the electromagnetic field, including light, is quantized and can be seen as a stream of particles, photons. In this picture, the electromagnetic force can be thought of as a bombardment of photons, as when one object is thrown to another to transmit a force. -
Yang-Mills Theory, Lattice Gauge Theory and Simulations
Yang-Mills theory, lattice gauge theory and simulations David M¨uller Institute of Analysis Johannes Kepler University Linz [email protected] May 22, 2019 1 Overview Introduction and physical context Classical Yang-Mills theory Lattice gauge theory Simulating the Glasma in 2+1D 2 Introduction and physical context 3 Yang-Mills theory I Formulated in 1954 by Chen Ning Yang and Robert Mills I A non-Abelian gauge theory with gauge group SU(Nc ) I A non-linear generalization of electromagnetism, which is a gauge theory based on U(1) I Gauge theories are a widely used concept in physics: the standard model of particle physics is based on a gauge theory with gauge group U(1) × SU(2) × SU(3) I All fundamental forces (electromagnetism, weak and strong nuclear force, even gravity) are/can be formulated as gauge theories 4 Classical Yang-Mills theory Classical Yang-Mills theory refers to the study of the classical equations of motion (Euler-Lagrange equations) obtained from the Yang-Mills action Main topic of this seminar: solving the classical equations of motion of Yang-Mills theory numerically Not topic of this seminar: quantum field theory, path integrals, lattice quantum chromodynamics (except certain methods), the Millenium problem related to Yang-Mills . 5 Classical Yang-Mills in the early universe 6 Classical Yang-Mills in the early universe Electroweak phase transition: the electro-weak force splits into the weak nuclear force and the electromagnetic force This phase transition can be studied using (extensions of) classical Yang-Mills theory Literature: I G. D. -
CALCULUS for the UTTERLY CONFUSED Has Proven to Be a Wonderful Review Enabling Me to Move Forward in Application of Calculus and Advanced Topics in Mathematics
TLFeBOOK WHAT READERS ARE SAYIN6 "I wish I had had this book when I needed it most, which was during my pre-med classes. It could have also been a great tool for me in a few medical school courses." Or. Kellie Aosley8 Recent Hedical school &a&ate "CALCULUS FOR THE UTTERLY CONFUSED has proven to be a wonderful review enabling me to move forward in application of calculus and advanced topics in mathematics. I found it easy to use and great as a reference for those darker aspects of calculus. I' Aaron Ladeville, Ekyiheeriky Student 'I1 am so thankful for CALCULUS FOR THE UTTERLY CONFUSED! I started out Clueless but ended with an All' Erika Dickstein8 0usihess school Student "As a non-traditional student one thing I have learned is the importance of material supplementary to texts. Especially in calculus it helps to have a second source, especially one as lucid and fun to read as CALCULUS FOR THE UTTERtY CONFUSED. Anyone, whether you are a math weenie or not, will get something out of this book. With this book, your chances of survival in the calculus jungle are greatly increased.'I Brad &3~ker,Physics Student Other books in the Utterly Conhrsed Series include: Financial Planning for the Utterly Confrcsed, Fifth Edition Job Hunting for the Utterly Confrcred Physics for the Utterly Confrred CALCULUS FOR THE UTTERLY CONFUSED Robert M. Oman Daniel M. Oman McGraw -Hill New York San Francisco Washington, D.C. Auckland Bogoth Caracas Lisbon London Madrid Mexico City Milan Montreal New Delhi San Juan Singapore Sydney Tokyo Toronto Library of Congress Cataloging-in-Publication Data Oman, Robert M. -
Weyl Spinors and the Helicity Formalism
Weyl spinors and the helicity formalism J. L. D´ıazCruz, Bryan Larios, Oscar Meza Aldama, Jonathan Reyes P´erez Facultad de Ciencias F´ısico-Matem´aticas, Benem´erita Universidad Aut´onomade Puebla, Av. San Claudio y 18 Sur, C. U. 72570 Puebla, M´exico Abstract. In this work we give a review of the original formulation of the relativistic wave equation for parti- cles with spin one-half. Traditionally (`ala Dirac), it's proposed that the \square root" of the Klein-Gordon (K-G) equation involves a 4 component (Dirac) spinor and in the non-relativistic limit it can be written as 2 equations for two 2 component spinors. On the other hand, there exists Weyl's formalism, in which one works from the beginning with 2 component Weyl spinors, which are the fundamental objects of the helicity formalism. In this work we rederive Weyl's equations directly, starting from K-G equation. We also obtain the electromagnetic interaction through minimal coupling and we get the interaction with the magnetic moment. As an example of the use of that formalism, we calculate Compton scattering using the helicity methods. Keywords: Weyl spinors, helicity formalism, Compton scattering. PACS: 03.65.Pm; 11.80.Cr 1 Introduction One of the cornerstones of contemporary physics is quantum mechanics, thanks to which great advances in the comprehension of nature at the atomic, and even subatomic level have been achieved. On the other hand, its applications have given place to a whole new technological revolution. Thus, the study of quantum physics is part of our scientific culture. -
Electroweak Symmetry Breaking (Historical Perspective)
Electroweak Symmetry Breaking (Historical Perspective) 40th SLAC Summer Institute · 2012 History is not just a thing of the past! 2 Symmetry Indistinguishable before and after a transformation Unobservable quantity would vanish if symmetry held Disorder order = reduced symmetry 3 Symmetry Bilateral Translational, rotational, … Ornamental Crystals 4 Symmetry CsI Fullerene C60 ball and stick created from a PDB using Piotr Rotkiewicz's [http://www.pirx.com/iMol/ iMol]. {{gfdl}} Source: English Wikipedia, 5 Symmetry (continuous) 6 Symmetry matters. 7 8 Symmetries & conservation laws Spatial translation Momentum Time translation Energy Rotational invariance Angular momentum QM phase Charge 9 Symmetric laws need not imply symmetric outcomes. 10 symmetries of laws ⇏ symmetries of outcomes by Wilson Bentley, via NOAA Photo Library Photo via NOAA Wilson Bentley, by Studies among the Snow Crystals ... CrystalsStudies amongSnow the ... 11 Broken symmetry is interesting. 12 Two-dimensional Ising model of ferromagnet http://boudin.fnal.gov/applet/IsingPage.html 13 Continuum of degenerate vacua 14 Nambu–Goldstone bosons V Betsy Devine Yoichiro Nambu �� 2 Massless NG boson 1 Massive scalar boson NGBs as spin waves, phonons, pions, … Jeffrey Goldstone 15 Symmetries imply forces. I: scale symmetry to unify EM, gravity Hermann Weyl (1918, 1929) 16 NEW Complex phase in QM ORIGINAL Global: free particle Local: interactions 17 Maxwell’s equations; QED massless spin-1 photon coupled to conserved charge no impediment to electron mass (eL & eR have same charge) James Clerk Maxwell (1861/2) 18 19 QED Fermion masses allowed Gauge-boson masses forbidden Photon mass term 1 2 µ 2 mγ A Aµ violates gauge invariance: AµA (Aµ ∂µΛ) (A ∂ Λ) = AµA µ ⇥ − µ − µ ⇤ µ Massless photon predicted 22 observed: mγ 10− me 20 Symmetries imply forces.