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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. -
God and Contrasting Interpretations of Quantum Theory
S & CB (2005), 17, 155–175 0954–4194 ROGER PAUL Relative State or It-from-Bit: God and Contrasting Interpretations of Quantum Theory In this article I explore theological implications of two contrasting interpretations of quantum theory: the Relative State interpretation of Hugh Everett III, and the It-from-Bit proposal of John A. Wheeler. The Relative State interpretation considers the Universal Wave Function to be a complete description of reality. Measurement results in a branching process that can be interpreted in terms of many worlds or many minds. I discuss issues of the identity of observers in a branching universe, the ways God may interact with the deterministic, isolated quantum universe and the relative nature of salvation history from a perspective within a branch. In contrast, irreversible, elementary acts of observation are considered to be the foundation of reality in the It-from-Bit proposal. Information gained through observer-participancy (the ‘bits’) constructs the fabric of the physical universe (‘it’), in a self-excited circuit. I discuss whether meaning, including religious faith, is a human construct, and whether creation is co- creation, in which divine power and supremacy are limited by the emergence of a participatory universe. By taking these two contrasting interpretations of quantum theory seriously, I hope to show that the interpretation of quantum mechanics we start from matters theologically. Key words: Quantum theory, theology, relative state, many worlds, it-from- bit, observer-participancy, human identity, divine simplicity, co-creation, salvation history. Theological thinking about quantum mechanics has tended to focus on the issue of Special Divine Action in relation to the uncertainty principle and quan- tum measurement.1 Inevitably, this work has been inconclusive, but has nev- ertheless succeeded in opening up the discussion. -
Life and Quantum Interconnectedness
Life and Quantum Interconnectedness Husin Alatas Theoretical Physics Division, Department of Physics, Faculty of Mathematics and Natural Sciences, IPB University; Center for Transdisciplinary and Sustainability Sciences, IPB University Presented at the Afternoon Discussion on Redesigning the Future (ADReF), CTSS-IPB University, June 30th 2020 Outline... Structure of Fundamental Matter Quantum World and its Weirdness Quantum Interpretations Life and Quantum Interconnectedness Disclaimer!… I am a theoretical physicist, not a philosopher… I have been trained as a reductionist, but now I am trying to be an integralist… Physics… Mainly about understanding nature phenomena based on OBSERVATION and MEASUREMENT conducted through scientific method Theoretical Physics?… Theoretical physics is a branch of physics that deals with rationalization, explanation, and prediction of phenomena in natural systems which is developed based on the combination of mathematics, abstraction, imagination, and intuition. Conducted research mainly based on curiosity with sky as its limit. Albert Einstein… “Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution”… Albert Szent-Györgyi… “As scientists attempt to understand a living system, they move down from dimension to dimension, from one level of complexity to the next lower level. I followed this course in my own studies. I went from anatomy to the study of tissues, then to electron microscopy and chemistry, and finally to quantum mechanics. This downward journey through the scale of dimensions has its irony, for in my search for the secret of life, I ended up with atoms and electrons, which have no life at all. Somewhere along the line life has run out through my fingers. -
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. -
2005 Annual Report American Physical Society
1 2005 Annual Report American Physical Society APS 20052 APS OFFICERS 2006 APS OFFICERS PRESIDENT: PRESIDENT: Marvin L. Cohen John J. Hopfield University of California, Berkeley Princeton University PRESIDENT ELECT: PRESIDENT ELECT: John N. Bahcall Leo P. Kadanoff Institue for Advanced Study, Princeton University of Chicago VICE PRESIDENT: VICE PRESIDENT: John J. Hopfield Arthur Bienenstock Princeton University Stanford University PAST PRESIDENT: PAST PRESIDENT: Helen R. Quinn Marvin L. Cohen Stanford University, (SLAC) University of California, Berkeley EXECUTIVE OFFICER: EXECUTIVE OFFICER: Judy R. Franz Judy R. Franz University of Alabama, Huntsville University of Alabama, Huntsville TREASURER: TREASURER: Thomas McIlrath Thomas McIlrath University of Maryland (Emeritus) University of Maryland (Emeritus) EDITOR-IN-CHIEF: EDITOR-IN-CHIEF: Martin Blume Martin Blume Brookhaven National Laboratory (Emeritus) Brookhaven National Laboratory (Emeritus) PHOTO CREDITS: Cover (l-r): 1Diffraction patterns of a GaN quantum dot particle—UCLA; Spring-8/Riken, Japan; Stanford Synchrotron Radiation Lab, SLAC & UC Davis, Phys. Rev. Lett. 95 085503 (2005) 2TESLA 9-cell 1.3 GHz SRF cavities from ACCEL Corp. in Germany for ILC. (Courtesy Fermilab Visual Media Service 3G0 detector studying strange quarks in the proton—Jefferson Lab 4Sections of a resistive magnet (Florida-Bitter magnet) from NHMFL at Talahassee LETTER FROM THE PRESIDENT APS IN 2005 3 2005 was a very special year for the physics community and the American Physical Society. Declared the World Year of Physics by the United Nations, the year provided a unique opportunity for the international physics community to reach out to the general public while celebrating the centennial of Einstein’s “miraculous year.” The year started with an international Launching Conference in Paris, France that brought together more than 500 students from around the world to interact with leading physicists. -
Black Hole Entropy, the Black Hole Information Paradox, and Time Travel Paradoxes from a New Perspective
Black hole entropy, the black hole information paradox, and time travel paradoxes from a new perspective Roland E. Allen Physics and Astronomy Department, Texas A&M University, College Station, TX USA [email protected] 1 Black hole entropy, the black hole information paradox, and time travel paradoxes from a new perspective Relatively simple but apparently novel ways are proposed for viewing three related subjects: black hole entropy, the black hole information paradox, and time travel paradoxes. (1) Gibbons and Hawking have completely explained the origin of the entropy of all black holes, including physical black holes – nonextremal and in 3-dimensional space – if one can identify their Euclidean path integral with a true thermodynamic partition function (ultimately based on microstates). An example is provided of a theory containing this feature. (2) There is unitary quantum evolution with no loss of information if the detection of Hawking radiation is regarded as a measurement process within the Everett interpretation of quantum mechanics. (3) The paradoxes of time travel evaporate when exposed to the light of quantum physics (again within the Everett interpretation), with quantum fields properly described by a path integral over a topologically nontrivial but smooth manifold. Keywords: Black hole entropy, information paradox, time travel 1. Introduction The three issues considered in this paper have all been thoroughly discussed by many of the best theorists for several decades, in hundreds of extremely erudite articles and a large number of books. Here we wish to add to the discussion with some relatively simple but apparently novel ideas that involve, first, the interpretation of the Euclidean path integral as a true thermodynamic partition function, and second, the Everett interpretation of quantum mechanics. -
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. -
'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. -
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 -
Cosmology's Rebirth and the Rise of the Dark Matter Problem
Closing in on the Cosmos: Cosmology’s Rebirth and the Rise of the Dark Matter Problem Jaco de Swart Abstract Influenced by the renaissance of general relativity that came to pass in the 1950s, the character of cosmology fundamentally changed in the 1960s as it be- came a well-established empirical science. Although observations went to dominate its practice, extra-theoretical beliefs and principles reminiscent of methodological debates in the 1950s kept playing an important tacit role in cosmological consider- ations. Specifically, belief in cosmologies that modeled a “closed universe” based on Machian insights remained influential. The rise of the dark matter problem in the early 1970s serves to illustrate this hybrid methodological character of cosmological science. Introduction In 1974, two landmark papers were published by independent research groups in the U.S. and Estonia that concluded on the existence of missing mass: a yet-unseen type of matter distributed throughout the universe whose presence could explain several problematic astronomical observations (Einasto et al. 1974a, Ostriker et al. 1974). The publication of these papers indicates the establishment of what is cur- rently known as the ‘dark matter’ problem – one of the most well-known anomalies in the prevailing cosmological model. According to this model, 85% of the uni- verse’s mass budget consists of dark matter. After four decades of multi-wavelength astronomical observations and high-energy particle physics experiments, the nature of this mass is yet to be determined.1 Jaco de Swart Institute of Physics & Vossius Center for the History of Humanities and Sciences University of Amsterdam, Science Park 904, Amsterdam, The Netherlands e-mail: [email protected] 1 For an overview of the physics, see e.g. -
Adobe Acrobat PDF Document
BIOGRAPHICAL SKETCH of HUGH EVERETT, III. Eugene Shikhovtsev ul. Dzerjinskogo 11-16, Kostroma, 156005, Russia [email protected] ©2003 Eugene B. Shikhovtsev and Kenneth W. Ford. All rights reserved. Sources used for this biographical sketch include papers of Hugh Everett, III stored in the Niels Bohr Library of the American Institute of Physics; Graduate Alumni Files in Seeley G. Mudd Manuscript Library, Princeton University; personal correspondence of the author; and information found on the Internet. The author is deeply indebted to Kenneth Ford for great assistance in polishing (often rewriting!) the English and for valuable editorial remarks and additions. If you want to get an interesting perspective do not think of Hugh as a traditional 20th century physicist but more of a Renaissance man with interests and skills in many different areas. He was smart and lots of things interested him and he brought the same general conceptual methodology to solve them. The subject matter was not so important as the solution ideas. Donald Reisler [1] Someone once noted that Hugh Everett should have been declared a “national resource,” and given all the time and resources he needed to develop new theories. Joseph George Caldwell [1a] This material may be freely used for personal or educational purposes provided acknowledgement is given to Eugene B. Shikhovtsev, author ([email protected]), and Kenneth W. Ford, editor ([email protected]). To request permission for other uses, contact the author or editor. CONTENTS 1 Family and Childhood Einstein letter (1943) Catholic University of America in Washington (1950-1953). Chemical engineering. Princeton University (1953-1956). -
Multiplicity in Everett's Interpretation of Quantum Mechanics
Multiplicity in Everett’s interpretation of quantum mechanics Louis Marchildon D´epartement de chimie, biochimie et physique, Universit´edu Qu´ebec, Trois-Rivi`eres, Qc. Canada G9A 5H7 email: louis.marchildon a uqtr.ca Abstract Everett’s interpretation of quantum mechanics was proposed to avoid problems inherent in the prevailing interpretational frame. It assumes that quantum mechanics can be applied to any system and that the state vector always evolves unitarily. It then claims that whenever an observable is measured, all possible results of the mea- surement exist. This notion of multiplicity has been understood in different ways by proponents of Everett’s theory. In fact the spec- trum of opinions on various ontological questions raised by Everett’s approach is rather large, as we attempt to document in this critical review. We conclude that much remains to be done to clarify and specify Everett’s approach. KEY WORDS: Everett, many worlds, multiplicity, quantum mechanics, interpretation. arXiv:1504.04835v2 [quant-ph] 8 Oct 2015 1 Introduction Everett’s ‘relative state formulation of quantum mechanics’ (1957a), also known as ‘the many-worlds interpretation,’ was proposed almost sixty years ago. It remained little more than a curiosity for a couple of decades, but has from then on attracted sustained attention. Its current status was synthe- sized and criticized in the remarkable recent monograph by Saunders et al. (2010), while Byrne (2010) uncovered at the same time the fascinating story of its genesis. 1 Everett’s original motivation was to provide a formulation of quantum mechanics that would avoid problems inherent in the then current interpre- tational frame, which drew both from the Copenhagen distinction between the quantum and the classical and from the Dirac–von Neumann collapse of the state vector.