Speed Limit: How the Search for an Absolute Frame of Reference in the Universe Led to Einstein’S Equation E =Mc2 — a History of Measurements of the Speed of Light
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Johann Marinsek VII 2014
Johann Marinsek VII 2014 THE NATURE OF ELECTRICITY WORK IN PROGRESS, SEE ALSO ARTICLES ON METALLIC BONDING, HEAT CAPACITIES AND GENUINE LATTICE BARS OF METALS THAT CONDUCT ELECTRICITY NO CONDUCTION ELECTRONS! ELECTRICITY IS THE PROPAGATION OF A POLARIZATION WAVE Johann Marinsek/2014 [email protected] Einstein: … free electrons do not exist in metals at all. Heisenberg:… electrons in metals were one proving ground for quantum mechanics. Abstract Einstein was a quantum mechanics sceptic. [ei] Heisenberg and the elite of physicists of the first half of the 20th century dissipated their time with non-existing conduction electrons of metals. [HBE] But the electronic gas according to Drude, Bloch, Fermi, Pauli and others simply does not exist. Therefore the explanation of electrical conductivity in terms of the electron gas is lacking the necessary foundation. The fictitious electron gas theory cannot explain the speed of electricity, which is roughly < c, the velocity of light. The phase velocity of an electron gas sound wave can never be the rationale for the speed of electricity. Obviously, flowing electrons cannot push each other through the wire like gaseous atoms can do. Recall that there are ions in the wire that slow electrons down... Therefore there is no analogy between sound speed and speed of electricity! The speed of electricity is that of a polarization wave. Like in a capacitor, a voltage polarizes the metallic dipoles of the wire. The propagation speed of the polarization depends on the dielectricity constant ε of the material. ε depends essentially on crystal structure. For carbon nano tubes polarization depends on diameter and chirality. -
Implementation of the Fizeau Aether Drag Experiment for An
Implementation of the Fizeau Aether Drag Experiment for an Undergraduate Physics Laboratory by Bahrudin Trbalic Submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Bachelor of Science in Physics at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY May 2020 c Massachusetts Institute of Technology 2020. All rights reserved. ○ Author................................................................ Department of Physics May 8, 2020 Certified by. Sean P. Robinson Lecturer of Physics Thesis Supervisor Certified by. Joseph A. Formaggio Professor of Physics Thesis Supervisor Accepted by . Nergis Mavalvala Associate Department Head, Department of Physics 2 Implementation of the Fizeau Aether Drag Experiment for an Undergraduate Physics Laboratory by Bahrudin Trbalic Submitted to the Department of Physics on May 8, 2020, in partial fulfillment of the requirements for the degree of Bachelor of Science in Physics Abstract This work presents the description and implementation of the historically significant Fizeau aether drag experiment in an undergraduate physics laboratory setting. The implementation is optimized to be inexpensive and reproducible in laboratories that aim to educate students in experimental physics. A detailed list of materials, experi- mental setup, and procedures is given. Additionally, a laboratory manual, preparatory materials, and solutions are included. Thesis Supervisor: Sean P. Robinson Title: Lecturer of Physics Thesis Supervisor: Joseph A. Formaggio Title: Professor of Physics 3 4 Acknowledgments I gratefully acknowledge the instrumental help of Prof. Joseph Formaggio and Dr. Sean P. Robinson for the guidance in this thesis work and in my academic life. The Experimental Physics Lab (J-Lab) has been the pinnacle of my MIT experience and I’m thankful for the time spent there. -
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 . -
Using Time As a Sustainable Tool to Control Daylight in Space
USING TIME AS A SUSTAINABLE TOOL TO CONTROL DAYLIGHT IN SPACE Creating the Chronoform SAMER EL SAYARY Beirut Arab University and Alexandria University, Egypt [email protected] Abstract. Just as Einstein's own Relativity Theory led Einstein to reject time, Feynman’s Sum over histories theory led him to describe time simply as a direction in space. Many artists tried to visualize time as Étienne-Jules Marey when he invented the chronophotography. While the wheel of development of chronophotography in the Victorian era had ended in inventing the motion picture, a lot of research is still in its earlier stages regarding the time as a shaping media for the architectural form. Using computer animation now enables us to use time as a flexible tool to be stretched and contracted to visualize the time dilation of the Einstein's special relativity. The presented work suggests using time as a sustainable tool to shape the generated form in response to the sun movement to control the amount of daylighting entering the space by stretching the time duration and contracting time frames at certain locations of the sun trajectory along a summer day to control the amount of daylighting in the morning and afternoon versus the noon time. INTRODUCTION According to most dictionaries (Oxford, 2011; Collins, 2011; Merriam- Webster, 2015) Time is defined as a nonspatial continued progress of unlimited duration of existence and events that succeed one another ordered in the past, present, and future regarded as a whole measured in units such as minutes, hours, days, months, or years. -
Physics 200 Problem Set 7 Solution Quick Overview: Although Relativity Can Be a Little Bewildering, This Problem Set Uses Just A
Physics 200 Problem Set 7 Solution Quick overview: Although relativity can be a little bewildering, this problem set uses just a few ideas over and over again, namely 1. Coordinates (x; t) in one frame are related to coordinates (x0; t0) in another frame by the Lorentz transformation formulas. 2. Similarly, space and time intervals (¢x; ¢t) in one frame are related to inter- vals (¢x0; ¢t0) in another frame by the same Lorentz transformation formu- las. Note that time dilation and length contraction are just special cases: it is time-dilation if ¢x = 0 and length contraction if ¢t = 0. 3. The spacetime interval (¢s)2 = (c¢t)2 ¡ (¢x)2 between two events is the same in every frame. 4. Energy and momentum are always conserved, and we can make e±cient use of this fact by writing them together in an energy-momentum vector P = (E=c; p) with the property P 2 = m2c2. In particular, if the mass is zero then P 2 = 0. 1. The earth and sun are 8.3 light-minutes apart. Ignore their relative motion for this problem and assume they live in a single inertial frame, the Earth-Sun frame. Events A and B occur at t = 0 on the earth and at 2 minutes on the sun respectively. Find the time di®erence between the events according to an observer moving at u = 0:8c from Earth to Sun. Repeat if observer is moving in the opposite direction at u = 0:8c. Answer: According to the formula for a Lorentz transformation, ³ u ´ 1 ¢tobserver = γ ¢tEarth-Sun ¡ ¢xEarth-Sun ; γ = p : c2 1 ¡ (u=c)2 Plugging in the numbers gives (notice that the c implicit in \light-minute" cancels the extra factor of c, which is why it's nice to measure distances in terms of the speed of light) 2 min ¡ 0:8(8:3 min) ¢tobserver = p = ¡7:7 min; 1 ¡ 0:82 which means that according to the observer, event B happened before event A! If we reverse the sign of u then 2 min + 0:8(8:3 min) ¢tobserver 2 = p = 14 min: 1 ¡ 0:82 2. -
Made to Measure. Practical Guide to Electrical Measurements in Low Voltage Switchboards V
Contact us A 250 500 200 150 V (b) 100 (a) 50 0 t Made to measure. Practical guide to electrical measurements in low voltage switchboards A 250 500 ABB SACE The data and illustrations are not binding. We reserve 200 the right to modify the contents of this document on the 150 Una divisione di ABB S.p.A. basis of technical development of the products, 100 Apparecchi Modulari without prior notice. 50 0 Viale dell’Industria, 18 Copyright 2010 ABB. All rights reserved. - 1.500 - CAL. 20010 Vittuone (MI) Tel.: 02 9034 1 Fax: 02 9034 7609 bol.it.abb.com www.abb.com V 80 V 60 2CSC445012D0201 - 12/2010 (f) 40 50 Hz 20 0 t Made to measure. Practical guide to electrical measurements in low voltage switchboards table of Made to measure. Practical guide to electrical measurements contents in low voltage switchboards 1 Electrical measurements 5.3.2 Current transformers ......................................................... 37 5.3.3 Voltage transformers ......................................................... 38 1.1 Why is it important to measure? .......................................... 3 5.3.4 Shunts for direct current .................................................... 38 1.2 Applicational contexts .......................................................... 4 1.3 Problems connected with energy networks ......................... 4 6 The measurements 1.4 Reducing consumption ........................................................ 7 1.5 Table of charges .................................................................. 8 6.1 TRMS Measurements -
The Concept of Field in the History of Electromagnetism
The concept of field in the history of electromagnetism Giovanni Miano Department of Electrical Engineering University of Naples Federico II ET2011-XXVII Riunione Annuale dei Ricercatori di Elettrotecnica Bologna 16-17 giugno 2011 Celebration of the 150th Birthday of Maxwell’s Equations 150 years ago (on March 1861) a young Maxwell (30 years old) published the first part of the paper On physical lines of force in which he wrote down the equations that, by bringing together the physics of electricity and magnetism, laid the foundations for electromagnetism and modern physics. Statue of Maxwell with its dog Toby. Plaque on E-side of the statue. Edinburgh, George Street. Talk Outline ! A brief survey of the birth of the electromagnetism: a long and intriguing story ! A rapid comparison of Weber’s electrodynamics and Maxwell’s theory: “direct action at distance” and “field theory” General References E. T. Wittaker, Theories of Aether and Electricity, Longam, Green and Co., London, 1910. O. Darrigol, Electrodynamics from Ampère to Einste in, Oxford University Press, 2000. O. M. Bucci, The Genesis of Maxwell’s Equations, in “History of Wireless”, T. K. Sarkar et al. Eds., Wiley-Interscience, 2006. Magnetism and Electricity In 1600 Gilbert published the “De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure” (On the Magnet and Magnetic Bodies, and on That Great Magnet the Earth). ! The Earth is magnetic ()*+(,-.*, Magnesia ad Sipylum) and this is why a compass points north. ! In a quite large class of bodies (glass, sulphur, …) the friction induces the same effect observed in the amber (!"#$%&'(, Elektron). Gilbert gave to it the name “electricus”. -
Keithley Instrumentation for Electrochemical Test Methods and Applications ––
Keithley Instrumentation for Electrochemical Test Methods and Applications –– APPLICATION NOTE Keithley Instrumentation for Electrochemical Test Methods and Applications APPLICATION NOTE With more than 60 years of measurement expertise, Keithley Cyclic Voltammetry Instruments is a world leader in advanced electronic test Cyclic voltammetry (CV), a type of potential sweep method, instrumentation. Our customers are scientists and engineers is the most commonly used electrochemical measurement in a wide range of research and industrial applications, technique, which typically uses a 3-electrode cell. Figure including many electrochemistry tests. Keithley manufactures 1 illustrates a typical electrochemical measurement circuit products that can source and measure current and voltage made up of an electrochemical cell, an adjustable voltage accurately. Electrochemistry disciplines that employ source (V ), an ammeter (A ), and a voltmeter (V ). The Keithley instrumentation include battery and energy storage, S M M three electrodes of the electrochemical cell are the working corrosion science, electrochemical deposition, organic electrode (WE), the reference electrode (RE), and the counter electronics, photo-electrochemistry, material research, electrode (CE). The voltage source (V ) for the potential sensors, and semiconductor materials and devices. Table 1 S scan is applied between the WE and CE. The potential (E) lists some of the test methods and applications that employ between the RE and WE is measured with the voltmeter, and Keithley products. the overall voltage (VS) is adjusted to maintain the desired Table 1. Electrochemistry test methods and applications potential at the WE with respect to the RE. The resulting Methods and Measurement current (i) flowing to or from the WE is measured with the Capabilities Applications ammeter (AM). -
Apparatus Named After Our Academic Ancestors, III
Digital Kenyon: Research, Scholarship, and Creative Exchange Faculty Publications Physics 2014 Apparatus Named After Our Academic Ancestors, III Tom Greenslade Kenyon College, [email protected] Follow this and additional works at: https://digital.kenyon.edu/physics_publications Part of the Physics Commons Recommended Citation “Apparatus Named After Our Academic Ancestors III”, The Physics Teacher, 52, 360-363 (2014) This Article is brought to you for free and open access by the Physics at Digital Kenyon: Research, Scholarship, and Creative Exchange. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Digital Kenyon: Research, Scholarship, and Creative Exchange. For more information, please contact [email protected]. Apparatus Named After Our Academic Ancestors, III Thomas B. Greenslade Jr. Citation: The Physics Teacher 52, 360 (2014); doi: 10.1119/1.4893092 View online: http://dx.doi.org/10.1119/1.4893092 View Table of Contents: http://scitation.aip.org/content/aapt/journal/tpt/52/6?ver=pdfcov Published by the American Association of Physics Teachers Articles you may be interested in Crystal (Xal) radios for learning physics Phys. Teach. 53, 317 (2015); 10.1119/1.4917450 Apparatus Named After Our Academic Ancestors — II Phys. Teach. 49, 28 (2011); 10.1119/1.3527751 Apparatus Named After Our Academic Ancestors — I Phys. Teach. 48, 604 (2010); 10.1119/1.3517028 Physics Northwest: An Academic Alliance Phys. Teach. 45, 421 (2007); 10.1119/1.2783150 From Our Files Phys. Teach. 41, 123 (2003); 10.1119/1.1542054 This article is copyrighted as indicated in the article. Reuse of AAPT content is subject to the terms at: http://scitation.aip.org/termsconditions. -
Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren
ELECTRICAL ENGINEERING – Vol. II - Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren ELECTRONIC VOLTMETERS AND AMMETERS Alessandro Ferrero Dipartimento di Elettrotecnica, Politecnico di Milano, Italy Halit Eren Curtin University of Technology, Perth, Western Australia Keywords: currents, voltages, measurements, standards, analog voltmeters, digital voltmeters, microvoltmeters, oscilloscopes Contents 1. Introduction. 2. Analog Meters 2.1. DC Analog Voltmeters and Ammeters 2.2. AC Analog Voltmeters and Ammeters 2.3. True rms Analog Voltmeters 3. Digital Meters 3.1. Dual-Slope DVMs 3.2. Successive-Approximation ADCs 3.3. AC Digital Voltmeters and Ammeters 3.4. Frequency Response of AC Meters 4. Radio-Frequency Microvoltmeters 5. Vacuum-Tube Voltmeters and Oscilloscopes 5.1. Analog Oscilloscopes 5.2. Digital Storage Oscilloscopes (DSOs) 5.3. Portable Oscilloscopes 5.4. High-Voltage Oscilloscopes Appendix Glossary Bibliography Biographical Sketches Summary Voltage UNESCOand current measurements are – esse EOLSSntial parts of engineering and science. Instruments that measure voltages and currents are called voltmeters and ammeters, respectively. ThereSAMPLE are two distinct types of voltmeterCHAPTERS and ammeter, which differ from each other by the operating principle that they are based on: electromechanical instruments and electronic instruments, which also include oscilloscopes. Electromechanical voltmeters and ammeters, including thermal-type instruments, represent early technology, but still are used in many applications. Basic elements of voltages and currents from the basic physical principles have been introduced in the electromechanical voltage and current measurements section. Also, voltage and currents standards have been dealt with in detail in other articles. ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. II - Electronic Voltmeters and Ammeters - Alessandro Ferrero, Halit Eren In this article, modern electronic voltmeters and ammeters are discussed. -
A Simple Atmospheric Electrical Instrument for Educational Use
A simple atmospheric electrical instrument for educational use A.J. Bennett1 and R.G. Harrison Department of Meteorology, The University of Reading P.O. Box 243, Earley Gate, Reading RG6 6BB, UK Abstract Electricity in the atmosphere provides an ideal topic for educational outreach in environmental science. To support this objective, a simple instrument to measure real atmospheric electrical parameters has been developed and its performance evaluated. This project compliments educational activities undertaken by the Coupling of Atmospheric Layers (CAL) European research collaboration. The new instrument is inexpensive to construct and simple to operate, readily allowing it to be used in schools as well as at the undergraduate University level. It is suited to students at a variety of different educational levels, as the results can be analysed with different levels of sophistication. Students can make measurements of the fair weather electric field and current density, thereby gaining an understanding of the electrical nature of the atmosphere. This work was stimulated by the centenary of the 1906 paper in which C.T.R. Wilson described a new apparatus to measure the electric field and conduction current density. Measurements using instruments based on the same principles continued regularly in the UK until 1979. The instrument proposed is based on the same physical principles as C.T.R. Wilson's 1906 instrument. Keywords: electrostatics; potential gradient; air-earth current density; meteorology; Submitted to Advances in Geosciences 1 E-mail: [email protected] 1 1. Introduction The phenomena of atmospheric electricity provide an ideal topic for stimulating lectures, talks and laboratory demonstrations. -
Technical White Paper the Atlas Asimi Interconnect Cable
Technical White Paper The Atlas Asimi Interconnect Cable The Ideal Cable In introducing the Asimi interconnect cable Atlas has tried to produce the closest approach to a theoretically perfect cable. In doing so it has gone back to the first principles of cable behaviour. In most respects the ideal cable would be two un-insulated conductors floating in free air. They would be widely spaced and form straight lines to ensure that the capacitive and inductive components would be zero. The cable would then be no more than a simple resistor with no complex impedance components or frequency response variations. The conductors should have a high degree of homogeneity to ensure that the speed of signal transmission is the same along the outside surface as along the outer core. This is because the high frequencies travel along the outer surface; the so-called “skin effect”. In this respect such hybrid conductors as silver-plated copper wire often offer a poor performance. The Conductors The Atlas Asimi cable uses only the finest available conductors, specifically ultra-high purity silver wires which have been made by the "Ohno Continuous Casting" or OCC process. In this process the mould is heated to a temperature which is much higher than the melting point of the silver in order to prevent nucleation at the mould wall and to ensure axial directional solidification. The strands produced in this process are always single crystals with a very smooth surface and the granular structure is aligned in the longitudinal length of the wire rather than being aligned across the wire.