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A Simple Derivation of the Lorentz Transformation and of the Related Velocity and Acceleration Formulae. Jean-Michel Levy
A simple derivation of the Lorentz transformation and of the related velocity and acceleration formulae. Jean-Michel Levy To cite this version: Jean-Michel Levy. A simple derivation of the Lorentz transformation and of the related velocity and acceleration formulae.. American Journal of Physics, American Association of Physics Teachers, 2007, 75 (7), pp.615-618. 10.1119/1.2719700. hal-00132616 HAL Id: hal-00132616 https://hal.archives-ouvertes.fr/hal-00132616 Submitted on 22 Feb 2007 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. A simple derivation of the Lorentz transformation and of the related velocity and acceleration formulae J.-M. L´evya Laboratoire de Physique Nucl´eaire et de Hautes Energies, CNRS - IN2P3 - Universit´es Paris VI et Paris VII, Paris. The Lorentz transformation is derived from the simplest thought experiment by using the simplest vector formula from elementary geometry. The result is further used to obtain general velocity and acceleration transformation equations. I. INTRODUCTION The present paper is organised as follows: in order to prevent possible objections which are often not Many introductory courses on special relativity taken care of in the derivation of the two basic effects (SR) use thought experiments in order to demon- using the light clock, we start by reviewing it briefly strate time dilation and length contraction from in section II. -
Introduction
INTRODUCTION Special Relativity Theory (SRT) provides a description for the kinematics and dynamics of particles in the four-dimensional world of spacetime. For mechanical systems, its predictions become evident when the particle velocities are high|comparable with the velocity of light. In this sense SRT is the physics of high velocity. As such it leads us into an unfamiliar world, quite beyond our everyday experience. What is it like? It is a fantasy world, where we encounter new meanings for such familiar concepts as time, space, energy, mass and momentum. A fantasy world, and yet also the real world: We may test it, play with it, think about it and experience it. These notes are about how to do those things. SRT was developed by Albert Einstein in 1905. Einstein felt impelled to reconcile an apparent inconsistency. According to the theory of electricity and magnetism, as formulated in the latter part of the nineteenth century by Maxwell and Lorentz, electromagnetic radiation (light) should travel with a velocity c, whose measured value should not depend on the velocity of either the source or the observer of the radiation. That is, c should be independent of the velocity of the reference frame with respect to which it is measured. This prediction seemed clearly inconsistent with the well-known rule for the addition of velocities, familiar from mechanics. The measured speed of a water wave, for example, will depend on the velocity of the reference frame with respect to which it is measured. Einstein, however, held an intuitive belief in the truth of the Maxwell-Lorentz theory, and worked out a resolution based on this belief. -
A Study of the Effects of Pair Production and Axionlike Particle
Washington University in St. Louis Washington University Open Scholarship Arts & Sciences Electronic Theses and Dissertations Arts & Sciences Summer 8-15-2016 A Study of the Effects of Pair Production and Axionlike Particle Oscillations on Very High Energy Gamma Rays from the Crab Pulsar Avery Michael Archer Washington University in St. Louis Follow this and additional works at: https://openscholarship.wustl.edu/art_sci_etds Recommended Citation Archer, Avery Michael, "A Study of the Effects of Pair Production and Axionlike Particle Oscillations on Very High Energy Gamma Rays from the Crab Pulsar" (2016). Arts & Sciences Electronic Theses and Dissertations. 828. https://openscholarship.wustl.edu/art_sci_etds/828 This Dissertation is brought to you for free and open access by the Arts & Sciences at Washington University Open Scholarship. It has been accepted for inclusion in Arts & Sciences Electronic Theses and Dissertations by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY IN ST. LOUIS Department of Physics Dissertation Examination Committee: James Buckley, Chair Francesc Ferrer Viktor Gruev Henric Krawzcynski Michael Ogilvie A Study of the Effects of Pair Production and Axionlike Particle Oscillations on Very High Energy Gamma Rays from the Crab Pulsar by Avery Michael Archer A dissertation presented to the Graduate School of Arts and Sciences of Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 2016 Saint Louis, Missouri copyright by Avery Michael Archer 2016 Contents List of Tablesv List of Figures vi Acknowledgments xvi Abstract xix 1 Introduction1 1.1 Gamma-Ray Astronomy............................. 1 1.2 Pulsars...................................... -
7. Gamma and X-Ray Interactions in Matter
Photon interactions in matter Gamma- and X-Ray • Compton effect • Photoelectric effect Interactions in Matter • Pair production • Rayleigh (coherent) scattering Chapter 7 • Photonuclear interactions F.A. Attix, Introduction to Radiological Kinematics Physics and Radiation Dosimetry Interaction cross sections Energy-transfer cross sections Mass attenuation coefficients 1 2 Compton interaction A.H. Compton • Inelastic photon scattering by an electron • Arthur Holly Compton (September 10, 1892 – March 15, 1962) • Main assumption: the electron struck by the • Received Nobel prize in physics 1927 for incoming photon is unbound and stationary his discovery of the Compton effect – The largest contribution from binding is under • Was a key figure in the Manhattan Project, condition of high Z, low energy and creation of first nuclear reactor, which went critical in December 1942 – Under these conditions photoelectric effect is dominant Born and buried in • Consider two aspects: kinematics and cross Wooster, OH http://en.wikipedia.org/wiki/Arthur_Compton sections http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=22551 3 4 Compton interaction: Kinematics Compton interaction: Kinematics • An earlier theory of -ray scattering by Thomson, based on observations only at low energies, predicted that the scattered photon should always have the same energy as the incident one, regardless of h or • The failure of the Thomson theory to describe high-energy photon scattering necessitated the • Inelastic collision • After the collision the electron departs -
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Arxiv:1809.04815V2 [Physics.Hist-Ph] 28 Jan 2020
Who discovered positron annihilation? Tim Dunker∗ (Dated: 29 January 2020) In the early 1930s, the positron, pair production, and, at last, positron annihila- tion were discovered. Over the years, several scientists have been credited with the discovery of the annihilation radiation. Commonly, Thibaud and Joliot have received credit for the discovery of positron annihilation. A conversation between Werner Heisenberg and Theodor Heiting prompted me to examine relevant publi- cations, when these were submitted and published, and how experimental results were interpreted in the relevant articles. I argue that it was Theodor Heiting— usually not mentioned at all in relevant publications—who discovered positron annihilation, and that he should receive proper credit. arXiv:1809.04815v2 [physics.hist-ph] 28 Jan 2020 ∗ tdu {at} justervesenet {dot} no 2 I. INTRODUCTION There is no doubt that the positron was discovered by Carl D. Anderson (e.g. Anderson, 1932; Hanson, 1961; Leone and Robotti, 2012) after its theoretical prediction by Paul A. M. Dirac (Dirac, 1928, 1931). Further, it is undoubted that Patrick M. S. Blackett and Giovanni P. S. Occhialini discovered pair production by taking photographs of electrons and positrons created from cosmic rays in a Wilson cloud chamber (Blackett and Occhialini, 1933). The answer to the question who experimentally discovered the reverse process—positron annihilation—has been less clear. Usually, Frédéric Joliot and Jean Thibaud receive credit for its discovery (e.g., Roqué, 1997, p. 110). Several of their contemporaries were enganged in similar research. In a letter correspondence with Werner Heisenberg Heiting and Heisenberg (1952), Theodor Heiting (see Appendix A for a rudimentary biography) claimed that it was he who discovered positron annihilation. -
Pkoduction of RELATIVISTIC ANTIHYDROGEN ATOMS by PAIR PRODUCTION with POSITRON CAPTURE*
SLAC-PUB-5850 May 1993 (T/E) PkODUCTION OF RELATIVISTIC ANTIHYDROGEN ATOMS BY PAIR PRODUCTION WITH POSITRON CAPTURE* Charles T. Munger and Stanley J. Brodsky Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 .~ and _- Ivan Schmidt _ _.._ Universidad Federico Santa Maria _. - .Casilla. 11 O-V, Valparaiso, Chile . ABSTRACT A beam of relativistic antihydrogen atoms-the bound state (Fe+)-can be created by circulating the beam of an antiproton storage ring through an internal gas target . An antiproton that passes through the Coulomb field of a nucleus of charge 2 will create e+e- pairs, and antihydrogen will form when a positron is created in a bound rather than a continuum state about the antiproton. The - cross section for this process is calculated to be N 4Z2 pb for antiproton momenta above 6 GeV/c. The gas target of Fermilab Accumulator experiment E760 has already produced an unobserved N 34 antihydrogen atoms, and a sample of _ N 760 is expected in 1995 from the successor experiment E835. No other source of antihydrogen exists. A simple method for detecting relativistic antihydrogen , - is -proposed and a method outlined of measuring the antihydrogen Lamb shift .g- ‘,. to N 1%. Submitted to Physical Review D *Work supported in part by Department of Energy contract DE-AC03-76SF00515 fSLAC’1 and in Dart bv Fondo National de InvestiPaci6n Cientifica v TecnoMcica. Chile. I. INTRODUCTION Antihydrogen, the simplest atomic bound state of antimatter, rf =, (e+$, has never. been observed. A 1on g- sought goal of atomic physics is to produce sufficient numbers of antihydrogen atoms to confirm the CPT invariance of bound states in quantum electrodynamics; for example, by verifying the equivalence of the+&/2 - 2.Py2 Lamb shifts of H and I?. -
David Bohn, Roger Penrose, and the Search for Non-Local Causality
David Bohm, Roger Penrose, and the Search for Non-local Causality Before they met, David Bohm and Roger Penrose each puzzled over the paradox of the arrow of time. After they met, the case for projective physical space became clearer. *** A machine makes pairs (I like to think of them as shoes); one of the pair goes into storage before anyone can look at it, and the other is sent down a long, long hallway. At the end of the hallway, a physicist examines the shoe.1 If the physicist finds a left hiking boot, he expects that a right hiking boot must have been placed in the storage bin previously, and upon later examination he finds that to be the case. So far, so good. The problem begins when it is discovered that the machine can make three types of shoes: hiking boots, tennis sneakers, and women’s pumps. Now the physicist at the end of the long hallway can randomly choose one of three templates, a metal sheet with a hole in it shaped like one of the three types of shoes. The physicist rolls dice to determine which of the templates to hold up; he rolls the dice after both shoes are out of the machine, one in storage and the other having started down the long hallway. Amazingly, two out of three times, the random choice is correct, and the shoe passes through the hole in the template. There can 1 This rendition of the Einstein-Podolsky-Rosen, 1935, delayed-choice thought experiment is paraphrased from Bernard d’Espagnat, 1981, with modifications via P. -
Electron-Positron Pairs in Physics and Astrophysics
Electron-positron pairs in physics and astrophysics: from heavy nuclei to black holes Remo Ruffini1,2,3, Gregory Vereshchagin1 and She-Sheng Xue1 1 ICRANet and ICRA, p.le della Repubblica 10, 65100 Pescara, Italy, 2 Dip. di Fisica, Universit`adi Roma “La Sapienza”, Piazzale Aldo Moro 5, I-00185 Roma, Italy, 3 ICRANet, Universit´ede Nice Sophia Antipolis, Grand Chˆateau, BP 2135, 28, avenue de Valrose, 06103 NICE CEDEX 2, France. Abstract Due to the interaction of physics and astrophysics we are witnessing in these years a splendid synthesis of theoretical, experimental and observational results originating from three fundamental physical processes. They were originally proposed by Dirac, by Breit and Wheeler and by Sauter, Heisenberg, Euler and Schwinger. For almost seventy years they have all three been followed by a continued effort of experimental verification on Earth-based experiments. The Dirac process, e+e 2γ, has been by − → far the most successful. It has obtained extremely accurate experimental verification and has led as well to an enormous number of new physics in possibly one of the most fruitful experimental avenues by introduction of storage rings in Frascati and followed by the largest accelerators worldwide: DESY, SLAC etc. The Breit–Wheeler process, 2γ e+e , although conceptually simple, being the inverse process of the Dirac one, → − has been by far one of the most difficult to be verified experimentally. Only recently, through the technology based on free electron X-ray laser and its numerous applications in Earth-based experiments, some first indications of its possible verification have been reached. The vacuum polarization process in strong electromagnetic field, pioneered by Sauter, Heisenberg, Euler and Schwinger, introduced the concept of critical electric 2 3 field Ec = mec /(e ). -
'Relativity: Special, General, Cosmological' by Rindler
Physical Sciences Educational Reviews Volume 8 Issue 1 p43 REVIEW: Relativity: special, general and cosmological by Wolfgang Rindler I have never heard anyone talk about relativity with a greater care for its meaning than the late Hermann Bondi. The same benign clarity that accompanied his talks permeated Relativity and Common Sense, his novel introductory approach to special relativity. Back in the Sixties, Alfred, Brian, Charles and David - I wonder what they would be called today - flashed stroboscopic light signals at each other and noted the frequencies at which they were received as they moved relative to each other. Bondi made of the simple composition of frequencies a beautiful natural law that you felt grateful to find in our universe’s particular canon. He thus simultaneously downplayed the common introduction of relativity as a rather unfortunate theory that makes the common sense addition of velocities unusable (albeit under some extreme rarely-experienced conditions), and renders intuition dangerous, and to be attempted only with a full suit of algebraic armour. A few years ago, I tried to teach a course following Bondi’s approach, incorporating some more advanced topics such as uniform acceleration. I enjoyed the challenge (probably more than the class did), but students without fluency in hyperbolic functions were able to tackle interesting questions about interstellar travel, which seemed an advantage. Wolfgang Rindler is no apologist for relativity either and his book is suffused with the concerns of a practicing physicist. Alongside Bondi’s book, this was the key recommendation on my suggested reading list and, from the contents of the new edition, would remain so on a future course. -
Worldline Sphaleron for Thermal Schwinger Pair Production
IMPERIAL-TP-2018-OG-1 HIP-2018-17-TH Worldline sphaleron for thermal Schwinger pair production Oliver Gould,1, 2, ∗ Arttu Rajantie,1, y and Cheng Xie1, z 1Department of Physics, Imperial College London, SW7 2AZ, UK 2Helsinki Institute of Physics, University of Helsinki, FI-00014, Finland (Dated: August 24, 2018) With increasing temperatures, Schwinger pair production changes from a quantum tunnelling to a classical, thermal process, determined by a worldline sphaleron. We show this and calculate the corresponding rate of pair production for both spinor and scalar quantum electrodynamics, including the semiclassical prefactor. For electron-positron pair production from a thermal bath of photons and in the presence of an electric field, the rate we derive is faster than both perturbative photon fusion and the zero temperature Schwinger process. We work to all-orders in the coupling and hence our results are also relevant to the pair production of (strongly coupled) magnetic monopoles in heavy-ion collisions. I. INTRODUCTION Schwinger rate, Γ(E; T ), takes the form, 1 In non-Abelian gauge theories, sphaleron processes, X Γ(E; T ) = c h(J · A)ni; (1) or thermal over-barrier transitions, have long been un- n derstood to dominate over quantum tunnelling transi- n=0 1 tions at high enough temperatures [1{4] . The same is where E is the magnitude of the electric field and T is true, for example, in gravitational theories [5]. On the the temperature. The leading term, c0, gives the one loop other hand, sphalerons have been conspicuously absent result, that of Schwinger [6], at zero temperature. -
Gamma-Ray Pulsars: Models and Predictions
Gamma-Ray Pulsars: Models and Predictions Alice K. Harding NASA Goddard Space Flight Center, Greenbelt MD 20771, USA Abstract. Pulsed emission from γ-ray pulsars originates inside the magnetosphere, from radiation by charged particles accelerated near the magnetic poles or in the outer gaps. In polar cap models, the high energy spectrum is cut off by magnetic pair production above an energy that is dependent on the local magnetic field strength. While most young pulsars with surface fields in the range B =1012 1013 G are expected to have high energy cutoffs around several GeV, the gamma-ray− spectra of old pulsars having lower surface fields may extend to 50 GeV. Although the gamma- ray emission of older pulsars is weaker, detecting pulsed emission at high energies from nearby sources would be an important confirmation of polar cap models. Outer gap models predict more gradual high-energy turnovers at around 10 GeV, but also predict an inverse Compton component extending to TeV energies. Detection of pulsed TeV emission, which would not survive attenuation at the polar caps, is thus an important test of outer gap models. Next-generation gamma-ray telescopes sensitive to GeV-TeV emission will provide critical tests of pulsar acceleration and emission mechanisms. INTRODUCTION The last decade has seen a large increase in the number of detected γ-ray pulsars. At GeV energies, the number has grown from two to at least six (and possibly nine) pulsar detections by the EGRET telescope on the Compton Gamma Ray Obser- vatory (CGRO) (Thompson 2000). However, even with the advance of imaging Cherenkov telescopes in both northern and southern hemispheres, the number of detections of pulsed emission at energies above 20 GeV (Weekes et al. -
RELATIVE REALITY a Thesis
RELATIVE REALITY _______________ A thesis presented to the faculty of the College of Arts & Sciences of Ohio University _______________ In partial fulfillment of the requirements for the degree Master of Science ________________ Gary W. Steinberg June 2002 © 2002 Gary W. Steinberg All Rights Reserved This thesis entitled RELATIVE REALITY BY GARY W. STEINBERG has been approved for the Department of Physics and Astronomy and the College of Arts & Sciences by David Onley Emeritus Professor of Physics and Astronomy Leslie Flemming Dean, College of Arts & Sciences STEINBERG, GARY W. M.S. June 2002. Physics Relative Reality (41pp.) Director of Thesis: David Onley The consequences of Einstein’s Special Theory of Relativity are explored in an imaginary world where the speed of light is only 10 m/s. Emphasis is placed on phenomena experienced by a solitary observer: the aberration of light, the Doppler effect, the alteration of the perceived power of incoming light, and the perception of time. Modified ray-tracing software and other visualization tools are employed to create a video that brings this imaginary world to life. The process of creating the video is detailed, including an annotated copy of the final script. Some of the less explored aspects of relativistic travel—discovered in the process of generating the video—are discussed, such as the perception of going backwards when actually accelerating from rest along the forward direction. Approved: David Onley Emeritus Professor of Physics & Astronomy 5 Table of Contents ABSTRACT........................................................................................................4