Teaching Symmetry in the Introductory Physics Curriculum
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A Mathematical Derivation of the General Relativistic Schwarzschild
A Mathematical Derivation of the General Relativistic Schwarzschild Metric An Honors thesis presented to the faculty of the Departments of Physics and Mathematics East Tennessee State University In partial fulfillment of the requirements for the Honors Scholar and Honors-in-Discipline Programs for a Bachelor of Science in Physics and Mathematics by David Simpson April 2007 Robert Gardner, Ph.D. Mark Giroux, Ph.D. Keywords: differential geometry, general relativity, Schwarzschild metric, black holes ABSTRACT The Mathematical Derivation of the General Relativistic Schwarzschild Metric by David Simpson We briefly discuss some underlying principles of special and general relativity with the focus on a more geometric interpretation. We outline Einstein’s Equations which describes the geometry of spacetime due to the influence of mass, and from there derive the Schwarzschild metric. The metric relies on the curvature of spacetime to provide a means of measuring invariant spacetime intervals around an isolated, static, and spherically symmetric mass M, which could represent a star or a black hole. In the derivation, we suggest a concise mathematical line of reasoning to evaluate the large number of cumbersome equations involved which was not found elsewhere in our survey of the literature. 2 CONTENTS ABSTRACT ................................. 2 1 Introduction to Relativity ...................... 4 1.1 Minkowski Space ....................... 6 1.2 What is a black hole? ..................... 11 1.3 Geodesics and Christoffel Symbols ............. 14 2 Einstein’s Field Equations and Requirements for a Solution .17 2.1 Einstein’s Field Equations .................. 20 3 Derivation of the Schwarzschild Metric .............. 21 3.1 Evaluation of the Christoffel Symbols .......... 25 3.2 Ricci Tensor Components ................. -
1-Crystal Symmetry and Classification-1.Pdf
R. I. Badran Solid State Physics Fundamental types of lattices and crystal symmetry Crystal symmetry: What is a symmetry operation? It is a physical operation that changes the positions of the lattice points at exactly the same places after and before the operation. In other words, it is an operation when applied to an object leaves it apparently unchanged. e.g. A translational symmetry is occurred, for example, when the function sin x has a translation through an interval x = 2 leaves it apparently unchanged. Otherwise a non-symmetric operation can be foreseen by the rotation of a rectangle through /2. There are two groups of symmetry operations represented by: a) The point groups. b) The space groups (these are a combination of point groups with translation symmetry elements). There are 230 space groups exhibited by crystals. a) When the symmetry operations in crystal lattice are applied about a lattice point, the point groups must be used. b) When the symmetry operations are performed about a point or a line in addition to symmetry operations performed by translations, these are called space group symmetry operations. Types of symmetry operations: There are five types of symmetry operations and their corresponding elements. 85 R. I. Badran Solid State Physics Note: The operation and its corresponding element are denoted by the same symbol. 1) The identity E: It consists of doing nothing. 2) Rotation Cn: It is the rotation about an axis of symmetry (which is called "element"). If the rotation through 2/n (where n is integer), and the lattice remains unchanged by this rotation, then it has an n-fold axis. -
From Relativistic Time Dilation to Psychological Time Perception
From relativistic time dilation to psychological time perception: an approach and model, driven by the theory of relativity, to combine the physical time with the time perceived while experiencing different situations. Andrea Conte1,∗ Abstract An approach, supported by a physical model driven by the theory of relativity, is presented. This approach and model tend to conciliate the relativistic view on time dilation with the current models and conclusions on time perception. The model uses energy ratios instead of geometrical transformations to express time dilation. Brain mechanisms like the arousal mechanism and the attention mechanism are interpreted and combined using the model. Matrices of order two are generated to contain the time dilation between two observers, from the point of view of a third observer. The matrices are used to transform an observer time to another observer time. Correlations with the official time dilation equations are given in the appendix. Keywords: Time dilation, Time perception, Definition of time, Lorentz factor, Relativity, Physical time, Psychological time, Psychology of time, Internal clock, Arousal, Attention, Subjective time, Internal flux, External flux, Energy system ∗Corresponding author Email address: [email protected] (Andrea Conte) 1Declarations of interest: none Preprint submitted to PsyArXiv - version 2, revision 1 June 6, 2021 Contents 1 Introduction 3 1.1 The unit of time . 4 1.2 The Lorentz factor . 6 2 Physical model 7 2.1 Energy system . 7 2.2 Internal flux . 7 2.3 Internal flux ratio . 9 2.4 Non-isolated system interaction . 10 2.5 External flux . 11 2.6 External flux ratio . 12 2.7 Total flux . -
Coordinates and Proper Time
Coordinates and Proper Time Edmund Bertschinger, [email protected] January 31, 2003 Now it came to me: . the independence of the gravitational acceleration from the na- ture of the falling substance, may be expressed as follows: In a gravitational ¯eld (of small spatial extension) things behave as they do in a space free of gravitation. This happened in 1908. Why were another seven years required for the construction of the general theory of relativity? The main reason lies in the fact that it is not so easy to free oneself from the idea that coordinates must have an immediate metrical meaning. | A. Einstein (quoted in Albert Einstein: Philosopher-Scientist, ed. P.A. Schilpp, 1949). 1. Introduction These notes supplement Chapter 1 of EBH (Exploring Black Holes by Taylor and Wheeler). They elaborate on the discussion of bookkeeper coordinates and how coordinates are related to actual physical distances and times. Also, a brief discussion of the classic Twin Paradox of special relativity is presented in order to illustrate the principal of maximal (or extremal) aging. Before going to details, let us review some jargon whose precise meaning will be important in what follows. You should be familiar with these words and their meaning. Spacetime is the four- dimensional playing ¯eld for motion. An event is a point in spacetime that is uniquely speci¯ed by giving its four coordinates (e.g. t; x; y; z). Sometimes we will ignore two of the spatial dimensions, reducing spacetime to two dimensions that can be graphed on a sheet of paper, resulting in a Minkowski diagram. -
Arxiv:1910.10745V1 [Cond-Mat.Str-El] 23 Oct 2019 2.2 Symmetry-Protected Time Crystals
A Brief History of Time Crystals Vedika Khemania,b,∗, Roderich Moessnerc, S. L. Sondhid aDepartment of Physics, Harvard University, Cambridge, Massachusetts 02138, USA bDepartment of Physics, Stanford University, Stanford, California 94305, USA cMax-Planck-Institut f¨urPhysik komplexer Systeme, 01187 Dresden, Germany dDepartment of Physics, Princeton University, Princeton, New Jersey 08544, USA Abstract The idea of breaking time-translation symmetry has fascinated humanity at least since ancient proposals of the per- petuum mobile. Unlike the breaking of other symmetries, such as spatial translation in a crystal or spin rotation in a magnet, time translation symmetry breaking (TTSB) has been tantalisingly elusive. We review this history up to recent developments which have shown that discrete TTSB does takes place in periodically driven (Floquet) systems in the presence of many-body localization (MBL). Such Floquet time-crystals represent a new paradigm in quantum statistical mechanics — that of an intrinsically out-of-equilibrium many-body phase of matter with no equilibrium counterpart. We include a compendium of the necessary background on the statistical mechanics of phase structure in many- body systems, before specializing to a detailed discussion of the nature, and diagnostics, of TTSB. In particular, we provide precise definitions that formalize the notion of a time-crystal as a stable, macroscopic, conservative clock — explaining both the need for a many-body system in the infinite volume limit, and for a lack of net energy absorption or dissipation. Our discussion emphasizes that TTSB in a time-crystal is accompanied by the breaking of a spatial symmetry — so that time-crystals exhibit a novel form of spatiotemporal order. -
Parts of Persons Identity and Persistence in a Perdurantist World
UNIVERSITÀ DEGLI STUDI DI MILANO Doctoral School in Philosophy and Human Sciences (XXXI Cycle) Department of Philosophy “Piero Martinetti” Parts of Persons Identity and persistence in a perdurantist world Ph.D. Candidate Valerio BUONOMO Tutors Prof. Giuliano TORRENGO Prof. Paolo VALORE Coordinator of the Doctoral School Prof. Marcello D’AGOSTINO Academic year 2017-2018 1 Content CONTENT ........................................................................................................................... 2 ACKNOWLEDGMENTS ........................................................................................................... 4 INTRODUCTION ................................................................................................................... 5 CHAPTER 1. PERSONAL IDENTITY AND PERSISTENCE...................................................................... 8 1.1. The persistence of persons and the criteria of identity over time .................................. 8 1.2. The accounts of personal persistence: a standard classification ................................... 14 1.2.1. Mentalist accounts of personal persistence ............................................................................ 15 1.2.2. Somatic accounts of personal persistence .............................................................................. 15 1.2.3. Anti-criterialist accounts of personal persistence ................................................................... 16 1.3. The metaphysics of persistence: the mereological account ......................................... -
Translational Symmetry and Microscopic Constraints on Symmetry-Enriched Topological Phases: a View from the Surface
PHYSICAL REVIEW X 6, 041068 (2016) Translational Symmetry and Microscopic Constraints on Symmetry-Enriched Topological Phases: A View from the Surface Meng Cheng,1 Michael Zaletel,1 Maissam Barkeshli,1 Ashvin Vishwanath,2 and Parsa Bonderson1 1Station Q, Microsoft Research, Santa Barbara, California 93106-6105, USA 2Department of Physics, University of California, Berkeley, California 94720, USA (Received 15 August 2016; revised manuscript received 26 November 2016; published 29 December 2016) The Lieb-Schultz-Mattis theorem and its higher-dimensional generalizations by Oshikawa and Hastings require that translationally invariant 2D spin systems with a half-integer spin per unit cell must either have a continuum of low energy excitations, spontaneously break some symmetries, or exhibit topological order with anyonic excitations. We establish a connection between these constraints and a remarkably similar set of constraints at the surface of a 3D interacting topological insulator. This, combined with recent work on symmetry-enriched topological phases with on-site unitary symmetries, enables us to develop a framework for understanding the structure of symmetry-enriched topological phases with both translational and on-site unitary symmetries, including the effective theory of symmetry defects. This framework places stringent constraints on the possible types of symmetry fractionalization that can occur in 2D systems whose unit cell contains fractional spin, fractional charge, or a projective representation of the symmetry group. As a concrete application, we determine when a topological phase must possess a “spinon” excitation, even in cases when spin rotational invariance is broken down to a discrete subgroup by the crystal structure. We also describe the phenomena of “anyonic spin-orbit coupling,” which may arise from the interplay of translational and on-site symmetries. -
The Theory of Relativity and Applications: a Simple Introduction
The Downtown Review Volume 5 Issue 1 Article 3 December 2018 The Theory of Relativity and Applications: A Simple Introduction Ellen Rea Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Engineering Commons, and the Physical Sciences and Mathematics Commons How does access to this work benefit ou?y Let us know! Recommended Citation Rea, Ellen. "The Theory of Relativity and Applications: A Simple Introduction." The Downtown Review. Vol. 5. Iss. 1 (2018) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol5/iss1/3 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Rea: The Theory of Relativity and Applications What if I told you that time can speed up and slow down? What if I told you that everything you think you know about gravity is a lie? When Albert Einstein presented his theory of relativity to the world in the early 20th century, he was proposing just that. And what’s more? He’s been proven correct. Einstein’s theory has two parts: special relativity, which deals with inertial reference frames and general relativity, which deals with the curvature of space- time. A surface level study of the theory and its consequences followed by a look at some of its applications will provide an introduction to one of the most influential scientific discoveries of the last century. -
Reconsidering Time Dilation of Special Theory of Relativity
International Journal of Advanced Research in Physical Science (IJARPS) Volume 5, Issue 8, 2018, PP 7-11 ISSN No. (Online) 2349-7882 www.arcjournals.org Reconsidering Time Dilation of Special Theory of Relativity Salman Mahmud Student of BIAM Model School and College, Bogra, Bangladesh *Corresponding Author: Salman Mahmud, Student of BIAM Model School and College, Bogra, Bangladesh Abstract : In classical Newtonian physics, the concept of time is absolute. With his theory of relativity, Einstein proved that time is not absolute, through time dilation. According to the special theory of relativity, time dilation is a difference in the elapsed time measured by two observers, either due to a velocity difference relative to each other. As a result a clock that is moving relative to an observer will be measured to tick slower than a clock that is at rest in the observer's own frame of reference. Through some thought experiments, Einstein proved the time dilation. Here in this article I will use my thought experiments to demonstrate that time dilation is incorrect and it was a great mistake of Einstein. 1. INTRODUCTION A central tenet of special relativity is the idea that the experience of time is a local phenomenon. Each object at a point in space can have it’s own version of time which may run faster or slower than at other objects elsewhere. Relative changes in the experience of time are said to happen when one object moves toward or away from other object. This is called time dilation. But this is wrong. Einstein’s relativity was based on two postulates: 1. -
About Symmetries in Physics
LYCEN 9754 December 1997 ABOUT SYMMETRIES IN PHYSICS Dedicated to H. Reeh and R. Stora1 Fran¸cois Gieres Institut de Physique Nucl´eaire de Lyon, IN2P3/CNRS, Universit´eClaude Bernard 43, boulevard du 11 novembre 1918, F - 69622 - Villeurbanne CEDEX Abstract. The goal of this introduction to symmetries is to present some general ideas, to outline the fundamental concepts and results of the subject and to situate a bit the following arXiv:hep-th/9712154v1 16 Dec 1997 lectures of this school. [These notes represent the write-up of a lecture presented at the fifth S´eminaire Rhodanien de Physique “Sur les Sym´etries en Physique” held at Dolomieu (France), 17-21 March 1997. Up to the appendix and the graphics, it is to be published in Symmetries in Physics, F. Gieres, M. Kibler, C. Lucchesi and O. Piguet, eds. (Editions Fronti`eres, 1998).] 1I wish to dedicate these notes to my diploma and Ph.D. supervisors H. Reeh and R. Stora who devoted a major part of their scientific work to the understanding, description and explo- ration of symmetries in physics. Contents 1 Introduction ................................................... .......1 2 Symmetries of geometric objects ...................................2 3 Symmetries of the laws of nature ..................................5 1 Geometric (space-time) symmetries .............................6 2 Internal symmetries .............................................10 3 From global to local symmetries ...............................11 4 Combining geometric and internal symmetries ...............14 -
Albert Einstein and Relativity
The Himalayan Physics, Vol.1, No.1, May 2010 Albert Einstein and Relativity Kamal B Khatri Department of Physics, PN Campus, Pokhara, Email: [email protected] Albert Einstein was born in Germany in 1879.In his the follower of Mach and his nascent concept helped life, Einstein spent his most time in Germany, Italy, him to enter the world of relativity. Switzerland and USA.He is also a Nobel laureate and worked mostly in theoretical physics. Einstein In 1905, Einstein propounded the “Theory of is best known for his theories of special and general Special Relativity”. This theory shows the observed relativity. I will not be wrong if I say Einstein a independence of the speed of light on the observer’s deep thinker, a philosopher and a real physicist. The state of motion. Einstein deduced from his concept philosophies of Henri Poincare, Ernst Mach and of special relativity the twentieth century’s best David Hume infl uenced Einstein’s scientifi c and known equation, E = m c2.This equation suggests philosophical outlook. that tiny amounts of mass can be converted into huge amounts of energy which in deed, became the Einstein at the age of 4, his father showed him a boon for the development of nuclear power. pocket compass, and Einstein realized that there must be something causing the needle to move, despite Einstein realized that the principle of special relativity the apparent ‘empty space’. This shows Einstein’s could be extended to gravitational fi elds. Since curiosity to the space from his childhood. The space Einstein believed that the laws of physics were local, of our intuitive understanding is the 3-dimensional described by local fi elds, he concluded from this that Euclidean space. -
Presentism/Eternalism and Endurantism/Perdurantism: Why the Unsubstantiality of the First Debate Implies That of the Second1
1 Presentism/Eternalism and Endurantism/Perdurantism: why the 1 unsubstantiality of the first debate implies that of the second Forthcoming in Philosophia Naturalis Mauro Dorato (Ph.D) Department of Philosophy University of Rome Three [email protected] tel. +393396070133 http://host.uniroma3.it/dipartimenti/filosofia/personale/doratoweb.htm Abstract The main claim that I want to defend in this paper is that the there are logical equivalences between eternalism and perdurantism on the one hand and presentism and endurantism on the other. By “logical equivalence” I mean that one position is entailed and entails the other. As a consequence of this equivalence, it becomes important to inquire into the question whether the dispute between endurantists and perdurantists is authentic, given that Savitt (2006) Dolev (2006) and Dorato (2006) have cast doubts on the fact that the debate between presentism and eternalism is about “what there is”. In this respect, I will conclude that also the debate about persistence in time has no ontological consequences, in the sense that there is no real ontological disagreement between the two allegedly opposite positions: as in the case of the presentism/eternalism debate, one can be both a perdurantist and an endurantist, depending on which linguistic framework is preferred. The main claim that I want to defend in this paper is that the there are logical equivalences between eternalism and perdurantism on the one hand and presentism and endurantism on the other. By “logical equivalence” I mean that one position is entailed and entails the other. As a consequence of this equivalence, it becomes important to inquire into the question whether the dispute between endurantists and perdurantists is authentic, given that Savitt (2006) Dolev (2006) and Dorato (2006) have cast doubts on the fact that the debate between presentism and eternalism is about “what there is”.