The Evolution of the Concepts of Energy, Momentum, and Mass From
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The Special Theory of Relativity
THE SPECIAL THEORY OF RELATIVITY Lecture Notes prepared by J D Cresser Department of Physics Macquarie University July 31, 2003 CONTENTS 1 Contents 1 Introduction: What is Relativity? 2 2 Frames of Reference 5 2.1 A Framework of Rulers and Clocks . 5 2.2 Inertial Frames of Reference and Newton’s First Law of Motion . 7 3 The Galilean Transformation 7 4 Newtonian Force and Momentum 9 4.1 Newton’s Second Law of Motion . 9 4.2 Newton’s Third Law of Motion . 10 5 Newtonian Relativity 10 6 Maxwell’s Equations and the Ether 11 7 Einstein’s Postulates 13 8 Clock Synchronization in an Inertial Frame 14 9 Lorentz Transformation 16 9.1 Length Contraction . 20 9.2 Time Dilation . 22 9.3 Simultaneity . 24 9.4 Transformation of Velocities (Addition of Velocities) . 24 10 Relativistic Dynamics 27 10.1 Relativistic Momentum . 28 10.2 Relativistic Force, Work, Kinetic Energy . 29 10.3 Total Relativistic Energy . 30 10.4 Equivalence of Mass and Energy . 33 10.5 Zero Rest Mass Particles . 34 11 Geometry of Spacetime 35 11.1 Geometrical Properties of 3 Dimensional Space . 35 11.2 Space Time Four Vectors . 38 11.3 Spacetime Diagrams . 40 11.4 Properties of Spacetime Intervals . 41 1 INTRODUCTION: WHAT IS RELATIVITY? 2 1 Introduction: What is Relativity? Until the end of the 19th century it was believed that Newton’s three Laws of Motion and the associated ideas about the properties of space and time provided a basis on which the motion of matter could be completely understood. -
Hypercomplex Algebras and Their Application to the Mathematical
Hypercomplex Algebras and their application to the mathematical formulation of Quantum Theory Torsten Hertig I1, Philip H¨ohmann II2, Ralf Otte I3 I tecData AG Bahnhofsstrasse 114, CH-9240 Uzwil, Schweiz 1 [email protected] 3 [email protected] II info-key GmbH & Co. KG Heinz-Fangman-Straße 2, DE-42287 Wuppertal, Deutschland 2 [email protected] March 31, 2014 Abstract Quantum theory (QT) which is one of the basic theories of physics, namely in terms of ERWIN SCHRODINGER¨ ’s 1926 wave functions in general requires the field C of the complex numbers to be formulated. However, even the complex-valued description soon turned out to be insufficient. Incorporating EINSTEIN’s theory of Special Relativity (SR) (SCHRODINGER¨ , OSKAR KLEIN, WALTER GORDON, 1926, PAUL DIRAC 1928) leads to an equation which requires some coefficients which can neither be real nor complex but rather must be hypercomplex. It is conventional to write down the DIRAC equation using pairwise anti-commuting matrices. However, a unitary ring of square matrices is a hypercomplex algebra by definition, namely an associative one. However, it is the algebraic properties of the elements and their relations to one another, rather than their precise form as matrices which is important. This encourages us to replace the matrix formulation by a more symbolic one of the single elements as linear combinations of some basis elements. In the case of the DIRAC equation, these elements are called biquaternions, also known as quaternions over the complex numbers. As an algebra over R, the biquaternions are eight-dimensional; as subalgebras, this algebra contains the division ring H of the quaternions at one hand and the algebra C ⊗ C of the bicomplex numbers at the other, the latter being commutative in contrast to H. -
(Special) Relativity
(Special) Relativity With very strong emphasis on electrodynamics and accelerators Better: How can we deal with moving charged particles ? Werner Herr, CERN Reading Material [1 ]R.P. Feynman, Feynman lectures on Physics, Vol. 1 + 2, (Basic Books, 2011). [2 ]A. Einstein, Zur Elektrodynamik bewegter K¨orper, Ann. Phys. 17, (1905). [3 ]L. Landau, E. Lifschitz, The Classical Theory of Fields, Vol2. (Butterworth-Heinemann, 1975) [4 ]J. Freund, Special Relativity, (World Scientific, 2008). [5 ]J.D. Jackson, Classical Electrodynamics (Wiley, 1998 ..) [6 ]J. Hafele and R. Keating, Science 177, (1972) 166. Why Special Relativity ? We have to deal with moving charges in accelerators Electromagnetism and fundamental laws of classical mechanics show inconsistencies Ad hoc introduction of Lorentz force Applied to moving bodies Maxwell’s equations lead to asymmetries [2] not shown in observations of electromagnetic phenomena Classical EM-theory not consistent with Quantum theory Important for beam dynamics and machine design: Longitudinal dynamics (e.g. transition, ...) Collective effects (e.g. space charge, beam-beam, ...) Dynamics and luminosity in colliders Particle lifetime and decay (e.g. µ, π, Z0, Higgs, ...) Synchrotron radiation and light sources ... We need a formalism to get all that ! OUTLINE Principle of Relativity (Newton, Galilei) - Motivation, Ideas and Terminology - Formalism, Examples Principle of Special Relativity (Einstein) - Postulates, Formalism and Consequences - Four-vectors and applications (Electromagnetism and accelerators) § ¤ some slides are for your private study and pleasure and I shall go fast there ¦ ¥ Enjoy yourself .. Setting the scene (terminology) .. To describe an observation and physics laws we use: - Space coordinates: ~x = (x, y, z) (not necessarily Cartesian) - Time: t What is a ”Frame”: - Where we observe physical phenomena and properties as function of their position ~x and time t. -
Basic Four-Momentum Kinematics As
L4:1 Basic four-momentum kinematics Rindler: Ch5: sec. 25-30, 32 Last time we intruduced the contravariant 4-vector HUB, (II.6-)II.7, p142-146 +part of I.9-1.10, 154-162 vector The world is inconsistent! and the covariant 4-vector component as implicit sum over We also introduced the scalar product For a 4-vector square we have thus spacelike timelike lightlike Today we will introduce some useful 4-vectors, but rst we introduce the proper time, which is simply the time percieved in an intertial frame (i.e. time by a clock moving with observer) If the observer is at rest, then only the time component changes but all observers agree on ✁S, therefore we have for an observer at constant speed L4:2 For a general world line, corresponding to an accelerating observer, we have Using this it makes sense to de ne the 4-velocity As transforms as a contravariant 4-vector and as a scalar indeed transforms as a contravariant 4-vector, so the notation makes sense! We also introduce the 4-acceleration Let's calculate the 4-velocity: and the 4-velocity square Multiplying the 4-velocity with the mass we get the 4-momentum Note: In Rindler m is called m and Rindler's I will always mean with . which transforms as, i.e. is, a contravariant 4-vector. Remark: in some (old) literature the factor is referred to as the relativistic mass or relativistic inertial mass. L4:3 The spatial components of the 4-momentum is the relativistic 3-momentum or simply relativistic momentum and the 0-component turns out to give the energy: Remark: Taylor expanding for small v we get: rest energy nonrelativistic kinetic energy for v=0 nonrelativistic momentum For the 4-momentum square we have: As you may expect we have conservation of 4-momentum, i.e. -
Principle of Relativity in Physics and in Epistemology Guang-Jiong
Principle of Relativity in Physics and in Epistemology Guang-jiong Ni Department of Physics, Fudan University, Shanghai 200433,China Department of Physics , Portland State University, Portland,OR97207,USA (Email: [email protected]) Abstract: The conceptual evolution of principle of relativity in the theory of special relativity is discussed in detail . It is intimately related to a series of difficulties in quantum mechanics, relativistic quantum mechanics and quantum field theory as well as to new predictions about antigravity and tachyonic neutrinos etc. I. Introduction: Two Postulates of Einstein As is well known, the theory of special relativity(SR) was established by Einstein in 1905 on two postulates (see,e.g.,[1]): Postulate 1: All inertial frames are equivalent with respect to all the laws of physics. Postulate 2: The speed of light in empty space always has the same value c. The postulate 1 , usually called as the “principle of relativity” , was accepted by all physicists in 1905 without suspicion whereas the postulate 2 aroused a great surprise among many physicists at that time. The surprise was inevitable and even necessary since SR is a totally new theory out broken from the classical physics. Both postulates are relativistic in essence and intimately related. This is because a law of physics is expressed by certain equation. When we compare its form from one inertial frame to another, a coordinate transformation is needed to check if its form remains invariant. And this Lorentz transformation must be established by the postulate 2 before postulate 1 can have quantitative meaning. Hence, as a metaphor, to propose postulate 1 was just like “ to paint a dragon on the wall” and Einstein brought it to life “by putting in the pupils of its eyes”(before the dragon could fly out of the wall) via the postulate 2[2]. -
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. -
Albert Einstein's Key Breakthrough — Relativity
{ EINSTEIN’S CENTURY } Albert Einstein’s key breakthrough — relativity — came when he looked at a few ordinary things from a different perspective. /// BY RICHARD PANEK Relativity turns 1001 How’d he do it? This question has shadowed Albert Einstein for a century. Sometimes it’s rhetorical — an expression of amazement that one mind could so thoroughly and fundamentally reimagine the universe. And sometimes the question is literal — an inquiry into how Einstein arrived at his special and general theories of relativity. Einstein often echoed the first, awestruck form of the question when he referred to the mind’s workings in general. “What, precisely, is ‘thinking’?” he asked in his “Autobiographical Notes,” an essay from 1946. In somebody else’s autobiographical notes, even another scientist’s, this question might have been unusual. For Einstein, though, this type of question was typical. In numerous lectures and essays after he became famous as the father of relativity, Einstein began often with a meditation on how anyone could arrive at any subject, let alone an insight into the workings of the universe. An answer to the literal question has often been equally obscure. Since Einstein emerged as a public figure, a mythology has enshrouded him: the lone- ly genius sitting in the patent office in Bern, Switzerland, thinking his little thought experiments until one day, suddenly, he has a “Eureka!” moment. “Eureka!” moments young Einstein had, but they didn’t come from nowhere. He understood what scientific questions he was trying to answer, where they fit within philosophical traditions, and who else was asking them. -
Equivalence Principle (WEP) of General Relativity Using a New Quantum Gravity Theory Proposed by the Authors Called Electro-Magnetic Quantum Gravity Or EMQG (Ref
WHAT ARE THE HIDDEN QUANTUM PROCESSES IN EINSTEIN’S WEAK PRINCIPLE OF EQUIVALENCE? Tom Ostoma and Mike Trushyk 48 O’HARA PLACE, Brampton, Ontario, L6Y 3R8 [email protected] Monday April 12, 2000 ACKNOWLEDGMENTS We wish to thank R. Mongrain (P.Eng) for our lengthy conversations on the nature of space, time, light, matter, and CA theory. ABSTRACT We provide a quantum derivation of Einstein’s Weak Equivalence Principle (WEP) of general relativity using a new quantum gravity theory proposed by the authors called Electro-Magnetic Quantum Gravity or EMQG (ref. 1). EMQG is manifestly compatible with Cellular Automata (CA) theory (ref. 2 and 4), and is also based on a new theory of inertia (ref. 5) proposed by R. Haisch, A. Rueda, and H. Puthoff (which we modified and called Quantum Inertia, QI). QI states that classical Newtonian Inertia is a property of matter due to the strictly local electrical force interactions contributed by each of the (electrically charged) elementary particles of the mass with the surrounding (electrically charged) virtual particles (virtual masseons) of the quantum vacuum. The sum of all the tiny electrical forces (photon exchanges with the vacuum particles) originating in each charged elementary particle of the accelerated mass is the source of the total inertial force of a mass which opposes accelerated motion in Newton’s law ‘F = MA’. The well known paradoxes that arise from considerations of accelerated motion (Mach’s principle) are resolved, and Newton’s laws of motion are now understood at the deeper quantum level. We found that gravity also involves the same ‘inertial’ electromagnetic force component that exists in inertial mass. -
Decay Rates and Cross Section
Decay rates and Cross section Ashfaq Ahmad National Centre for Physics Outlines Introduction Basics variables used in Exp. HEP Analysis Decay rates and Cross section calculations Summary 11/17/2014 Ashfaq Ahmad 2 Standard Model With these particles we can explain the entire matter, from atoms to galaxies In fact all visible stable matter is made of the first family, So Simple! Many Nobel prizes have been awarded (both theory/Exp. side) 11/17/2014 Ashfaq Ahmad 3 Standard Model Why Higgs Particle, the only missing piece until July 2012? In Standard Model particles are massless =>To explain the non-zero mass of W and Z bosons and fermions masses are generated by the so called Higgs mechanism: Quarks and leptons acquire masses by interacting with the scalar Higgs field (amount coupling strength) 11/17/2014 Ashfaq Ahmad 4 Fundamental Fermions 1st generation 2nd generation 3rd generation Dynamics of fermions described by Dirac Equation 11/17/2014 Ashfaq Ahmad 5 Experiment and Theory It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong. Richard P. Feynman A theory is something nobody believes except the person who made it, An experiment is something everybody believes except the person who made it. Albert Einstein 11/17/2014 Ashfaq Ahmad 6 Some Basics Mandelstam Variables In a two body scattering process of the form 1 + 2→ 3 + 4, there are 4 four-vectors involved, namely pi (i =1,2,3,4) = (Ei, pi) Three Lorentz Invariant variables namely s, t and u are defined. -
Quantum Mechanical Laws - Bogdan Mielnik and Oscar Rosas-Ruiz
FUNDAMENTALS OF PHYSICS – Vol. I - Quantum Mechanical Laws - Bogdan Mielnik and Oscar Rosas-Ruiz QUANTUM MECHANICAL LAWS Bogdan Mielnik and Oscar Rosas-Ortiz Departamento de Física, Centro de Investigación y de Estudios Avanzados, México Keywords: Indeterminism, Quantum Observables, Probabilistic Interpretation, Schrödinger’s cat, Quantum Control, Entangled States, Einstein-Podolski-Rosen Paradox, Canonical Quantization, Bell Inequalities, Path integral, Quantum Cryptography, Quantum Teleportation, Quantum Computing. Contents: 1. Introduction 2. Black body radiation: the lateral problem becomes fundamental. 3. The discovery of photons 4. Compton’s effect: collisions confirm the existence of photons 5. Atoms: the contradictions of the planetary model 6. The mystery of the allowed energy levels 7. Luis de Broglie: particles or waves? 8. Schrödinger’s wave mechanics: wave vibrations explain the energy levels 9. The statistical interpretation 10. The Schrödinger’s picture of quantum theory 11. The uncertainty principle: instrumental and mathematical aspects. 12. Typical states and spectra 13. Unitary evolution 14. Canonical quantization: scientific or magic algorithm? 15. The mixed states 16. Quantum control: how to manipulate the particle? 17. Measurement theory and its conceptual consequences 18. Interpretational polemics and paradoxes 19. Entangled states 20. Dirac’s theory of the electron as the square root of the Klein-Gordon law 21. Feynman: the interference of virtual histories 22. Locality problems 23. The idea UNESCOof quantum computing and future – perspectives EOLSS 24. Open questions Glossary Bibliography Biographical SketchesSAMPLE CHAPTERS Summary The present day quantum laws unify simple empirical facts and fundamental principles describing the behavior of micro-systems. A parallel but different component is the symbolic language adequate to express the ‘logic’ of quantum phenomena. -
Relativistic Kinematics & Dynamics Momentum and Energy
Physics 106a, Caltech | 3 December, 2019 Lecture 18 { Relativistic kinematics & dynamics Momentum and energy Our discussion of 4-vectors in general led us to the energy-momentum 4-vector p with components in some inertial frame (E; ~p) = (mγu; mγu~u) with ~u the velocity of the particle in that inertial 2 −1=2 1 2 frame and γu = (1 − u ) . The length-squared of the 4-vector is (since u = 1) p2 = m2 = E2 − p2 (1) where the last expression is the evaluation in some inertial frame and p = j~pj. In conventional units this is E2 = p2c2 + m2c4 : (2) For a light particle (photon) m = 0 and so E = p (going back to c = 1). Thus the energy-momentum 4-vector for a photon is E(1; n^) withn ^ the direction of propagation. This is consistent with the quantum expressions E = hν; ~p = (h/λ)^n with ν the frequency and λ the wave length, and νλ = 1 (the speed of light) We are led to the expression for the relativistic 3-momentum and energy m~u m ~p = p ;E = p : (3) 1 − u2 1 − u2 Note that ~u = ~p=E. The frame independent statement that the energy-momentum 4-vector is conserved leads to the conservation of this 3-momentum and energy in each inertial frame, with the new implication that mass can be converted to and from energy. Since (E; ~p) form the components of a 4-vector they transform between inertial frames in the same way as (t; ~x), i.e. in our standard configuration 0 px = γ(px − vE) (4) 0 py = py (5) 0 pz = pz (6) 0 E = γ(E − vpx) (7) and the inverse 0 0 px = γ(px + vE ) (8) 0 py = py (9) 0 pz = pz (10) 0 0 E = γ(E + vpx) (11) These reduce to the Galilean expressions for small particle speeds and small transformation speeds. -
Relativistic Kinematics of Particle Interactions Introduction
le kin rel.tex Relativistic Kinematics of Particle Interactions byW von Schlipp e, March2002 1. Notation; 4-vectors, covariant and contravariant comp onents, metric tensor, invariants. 2. Lorentz transformation; frequently used reference frames: Lab frame, centre-of-mass frame; Minkowski metric, rapidity. 3. Two-b o dy decays. 4. Three-b o dy decays. 5. Particle collisions. 6. Elastic collisions. 7. Inelastic collisions: quasi-elastic collisions, particle creation. 8. Deep inelastic scattering. 9. Phase space integrals. Intro duction These notes are intended to provide a summary of the essentials of relativistic kinematics of particle reactions. A basic familiarity with the sp ecial theory of relativity is assumed. Most derivations are omitted: it is assumed that the interested reader will b e able to verify the results, which usually requires no more than elementary algebra. Only the phase space calculations are done in some detail since we recognise that they are frequently a bit of a struggle. For a deep er study of this sub ject the reader should consult the monograph on particle kinematics byByckling and Ka jantie. Section 1 sets the scene with an intro duction of the notation used here. Although other notations and conventions are used elsewhere, I present only one version which I b elieveto b e the one most frequently encountered in the literature on particle physics, notably in such widely used textb o oks as Relativistic Quantum Mechanics by Bjorken and Drell and in the b o oks listed in the bibliography. This is followed in section 2 by a brief discussion of the Lorentz transformation.