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Is the Universe Expanding?: an Historical and Philosophical Perspective for Cosmologists Starting Anew
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 6-1996 Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew David A. Vlosak Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Cosmology, Relativity, and Gravity Commons Recommended Citation Vlosak, David A., "Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew" (1996). Master's Theses. 3474. https://scholarworks.wmich.edu/masters_theses/3474 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. IS THEUN IVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STAR TING ANEW by David A Vlasak A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements forthe Degree of Master of Arts Department of Philosophy Western Michigan University Kalamazoo, Michigan June 1996 IS THE UNIVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STARTING ANEW David A Vlasak, M.A. Western Michigan University, 1996 This study addresses the problem of how scientists ought to go about resolving the current crisis in big bang cosmology. Although this problem can be addressed by scientists themselves at the level of their own practice, this study addresses it at the meta level by using the resources offered by philosophy of science. There are two ways to resolve the current crisis. -
Emil Wolf Institutional Interviews Journal Interviews EMERGING RESEARCH FRONTS - 2009 Podcasts
Home About Scientific Press Room Contact Us ● ScienceWatch Home ● Inside This Month... ● Interviews Featured Interviews Author Commentaries 2009 : April 2009 - Emerging Research Fronts : Emil Wolf Institutional Interviews Journal Interviews EMERGING RESEARCH FRONTS - 2009 Podcasts April 2009 ● Analyses Emil Wolf talks with ScienceWatch.com and answers a few questions about this month's Featured Analyses Emerging Research Front Paper in the field of Physics. What's Hot In... Article: Unified theory of coherence and polarization of random Special Topics electromagnetic beams Authors: Wolf, E Journal: PHYS LETT A, 312 (5-6): 263-267 JUN 16 2003 ● Data & Rankings Addresses: Univ Rochester, Dept Phys & Astron, 601 Elmwood Ave, Rochester, NY 14627 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Sci-Bytes Univ Rochester, Inst Opt, Rochester, NY 14627 USA. Fast Breaking Papers New Hot Papers Emerging Research Fronts Fast Moving Fronts Corporate Research Fronts Why do you think your paper is highly cited? Research Front Maps Because the theory presented in that paper makes it possible to provide solutions to a number of scientific, technological, and medical problems which could not have been done previously. Current Classics Top Topics Does it describe a new discovery, methodology, or synthesis of knowledge? Rising Stars The discovery reported in the paper provides a synthesis of two branches of optics, known as the theory of coherence and the theory of polarization of light. Until the publication of my paper, these two subjects New Entrants had always been treated independently of each other. Prior to the invention of the laser, almost 50 years Country Profiles ago, the available sources which generate light, such as a light bulb and the sun, may be shown to have, on a short time scale, irregularities (called fluctuations) which make it impossible to use such light for some applications. -
Ionization Based State Read out of a Single 87-Rb Atom
Ionization Based State Read Out of a single 87Rb Atom Michael Krug M¨unchen2017 Ionization Based State Read Out of a single 87Rb Atom Michael Krug Dissertation an der Fakult¨atf¨urPhysik der Ludwig{Maximilians{Universit¨at M¨unchen vorgelegt von Michael Krug aus M¨unchen M¨unchen, den 8. Dezember 2017 Erstgutachter: Prof. Dr. Harald Weinfurter Zweitgutachter: Prof. J¨orgSchreiber Tag der m¨undlichen Pr¨ufung:30. Januar 2018 "After sleeping through a hundred million centuries we have finally opened our eyes on a sumptuous planet sparkling with color, bountiful with life. Within decades, we must close our eyes again. Isn't it a noble, enlightened way of spending our brief time in the sun to work at understanding the universe and how we have come to wake up in it? This is how I answer when I am asked, as I am surprisingly often, why I bother to get up in the mornings." Richard Dawkins Zusammenfassung Verschr¨ankung ist nach E. Schr¨odingerdie fundamentale Charakteristik der 1 Quantenmechanik. Einerseits lebt ein verschr¨ankterZustand zweiter Spin- 2 -Teilchen auf einem vier-dimensionalem Hilbert-Raum und die Theorie, um diesen Zustand zu beschreiben, ist hinreichend verstanden. Auf der anderen Seite ist die experimentelle Realisierung verschr¨ankter Systeme, im Besonderen hybride Licht-Materie-Systeme und deren Nachweis noch immer ein anspruchsvoller Prozess. Ausgehend von einem Quantensystem, das aus einem verschr¨anktenAtom-Photon-Paar besteht, wird hier die experimentelle Anwendung des entanglement swapping Protokolls verwendet, um einen Grundknotenpunkt einer Quanten-Repeater Verbindung aufzubauen, die aus zwei verschr¨anktenAtomen besteht. Die angek¨undigteErzeugung von Ver- schr¨ankungzwischen zwei Atomen bereitet den Weg hin zu einem beweiskr¨aftigem Experiment, um eine lokal-realistische Beschreibung der Welt zu falsifizieren. -
Physics 305, Fall 2008 Problem Set 8 Due Thursday, December 3
Physics 305, Fall 2008 Problem Set 8 due Thursday, December 3 1. Einstein A and B coefficients (25 pts): This problem is to make sure that you have read and understood Griffiths 9.3.1. Consider a system that consists of atoms with two energy levels E1 and E2 and a thermal gas of photons. There are N1 atoms with energy E1, N2 atoms with energy E2 and the energy density of photons with frequency ! = (E2 − E1)=~ is W (!). In thermal equilbrium at temperature T , W is given by the Planck distribution: ~!3 1 W (!) = 2 3 : π c exp(~!=kBT ) − 1 According to Einstein, this formula can be understood by assuming the following rules for the interaction between the atoms and the photons • Atoms with energy E1 can absorb a photon and make a transition to the excited state with energy E2; the probability per unit time for this transition to take place is proportional to W (!), and therefore given by Pabs = B12W (!) for some constant B12. • Atoms with energy E2 can make a transition to the lower energy state via stimulated emission of a photon. The probability per unit time for this to happen is Pstim = B21W (!) for some constant B21. • Atoms with energy E2 can also fall back into the lower energy state via spontaneous emission. The probability per unit time for spontaneous emission is independent of W (!). Let's call this probability Pspont = A21 : A21, B21, and B12 are known as Einstein coefficients. a. Write a differential equation for the time dependence of the occupation numbers N1 and N2. -
Inis: Terminology Charts
IAEA-INIS-13A(Rev.0) XA0400071 INIS: TERMINOLOGY CHARTS agree INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, AUGUST 1970 INISs TERMINOLOGY CHARTS TABLE OF CONTENTS FOREWORD ... ......... *.* 1 PREFACE 2 INTRODUCTION ... .... *a ... oo 3 LIST OF SUBJECT FIELDS REPRESENTED BY THE CHARTS ........ 5 GENERAL DESCRIPTOR INDEX ................ 9*999.9o.ooo .... 7 FOREWORD This document is one in a series of publications known as the INIS Reference Series. It is to be used in conjunction with the indexing manual 1) and the thesaurus 2) for the preparation of INIS input by national and regional centrea. The thesaurus and terminology charts in their first edition (Rev.0) were produced as the result of an agreement between the International Atomic Energy Agency (IAEA) and the European Atomic Energy Community (Euratom). Except for minor changesq the terminology and the interrela- tionships btween rms are those of the December 1969 edition of the Euratom Thesaurus 3) In all matters of subject indexing and ontrol, the IAEA followed the recommendations of Euratom for these charts. Credit and responsibility for the present version of these charts must go to Euratom. Suggestions for improvement from all interested parties. particularly those that are contributing to or utilizing the INIS magnetic-tape services are welcomed. These should be addressed to: The Thesaurus Speoialist/INIS Section Division of Scientific and Tohnioal Information International Atomic Energy Agency P.O. Box 590 A-1011 Vienna, Austria International Atomic Energy Agency Division of Sientific and Technical Information INIS Section June 1970 1) IAEA-INIS-12 (INIS: Manual for Indexing) 2) IAEA-INIS-13 (INIS: Thesaurus) 3) EURATOM Thesaurusq, Euratom Nuclear Documentation System. -
Fundamentals of Radiative Transfer
RADIATIVE PROCESSE S IN ASTROPHYSICS GEORGE B. RYBICKI, ALAN P. LIGHTMAN Copyright 0 2004 WY-VCHVerlag GmbH L Co. KCaA FUNDAMENTALS OF RADIATIVE TRANSFER 1.1 THE ELECTROMAGNETIC SPECTRUM; ELEMENTARY PROPERTIES OF RADIATION Electromagnetic radiation can be decomposed into a spectrum of con- stituent components by a prism, grating, or other devices, as was dis- covered quite early (Newton, 1672, with visible light). The spectrum corresponds to waves of various wavelengths and frequencies, related by Xv=c, where v is the frequency of the wave, h is its wavelength, and c-3.00~10" cm s-I is the free space velocity of light. (For waves not traveling in a vacuum, c is replaced by the appropriate velocity of the wave in the medium.) We can divide the spectrum up into various regions, as is done in Figure 1.1. For convenience we have given the energy E = hv and temperature T= E/k associated with each wavelength. Here h is Planck's constant = 6.625 X erg s, and k is Boltzmann's constant = 1.38 X erg K-I. This chart will prove to be quite useful in converting units or in getting a quick view of the relevant magnitude of quantities in a given portion of the spectrum. The boundaries between different regions are somewhat arbitrary, but conform to accepted usage. 1 2 Fundamentals of Radiatiw Transfer -6 -5 -4 -3 -2 -1 0 1 2 1 I 1 I I I I 1 1 log A (cm) Wavelength I I I I I log Y IHr) Frequency 0 -1 -2 -3 -4 -5 -6 I I I I I I I log Elev) Energy 43 21 0-1 I I 1 I I I log T("K)Temperature Y ray X-ray UV Visible IR Radio Figum 1.1 The electromagnetic spctnun. -
Principles of Optics
Principles of optics Electromagnetic theory of propagation, interference and diffraction of light MAX BORN MA, Dr Phil, FRS Nobel Laureate Formerly Professor at the Universities of Göttingen and Edinburgh and EMIL WOLF PhD, DSc Wilson Professor of Optical Physics, University of Rochester, NY with contributions by A.B.BHATIA, P.C.CLEMMOW, D.GABOR, A.R.STOKES, A.M.TAYLOR, P.A.WAYMAN AND W.L.WILCOCK SEVENTH (EXPANDED) EDITION CAMBRIDGE UNIVERSITY PRESS Contents Historical introduction xxv I Basic properties of the electromagnetic field 1 1.1 The electromagnetic field 1 1.1.1 Maxwells equations 1 1.1.2 Material equations 2 1.1.3 Boundary conditions at a surface of discontinuity 4 1.1.4 The energy law of the electromagnetic field 7 1.2 The wave equation and the velocity of light 11 1.3 Scalar waves 14 1.3.1 Plane waves 15 1.3.2 Spherical waves 16 1.3.3 Harmonie waves. The phase velocity 16 1.3.4 Wave packets. The group velocity 19 1.4 Vector waves 24 1.4.1 The general electromagnetic plane wave 24 1.4.2 The harmonic electromagnetic plane wave 25 (a) Elliptic polarization 25 (b) Linear and circular polarization 29 (c) Characterization of the state of polarization by Stoltes parameters 31 1.4.3 Harmonie vector waves of arbitrary form 33 1.5 Reflection and refraction of a plane wave 38 1.5.1 The laws of reflection and refraction 38 1.5.2 Fresnel formulae 40 1.5.3 The reflectivity and transmissivity; polarization an reflection and refraction 43 1.5.4 Total reflection 49 1.6 Wave propagation in a stratified medium. -
Colloquiumcolloquium
ColloquiumColloquium History and solution of the phase problem in the theory of structure determination of crystals from X-ray diffraction experiments Emil Wolf Department of Physics and Astronomy Institute of Optics University of Rochester 3:45 pm, Wednesday, Nov 18, 2009 B.Sc. and Ph.D. Bristol University Baush & Lomb 109 D.Sc. University of Edinburgh U. of Rochester 1959 - Tea 3:30 B&L Lobby Wilson Professor of Optical Physics JointlyJointly sponsoredsponsored byby The most important researches carried out in this field will be reviewed and a recently DepartmentDepartment ofof PhysicsPhysics andand AstronomyAstronomy obtained solution of the phase problem will be presented. History and solution of the phase problem in the theory of structure determination of crystals from X-ray diffraction experiments Emil Wolf Department of Physics and Astronomy and The Institute of Optics University of Rochester Abstract Since the pioneering work of Max von Laue on interference and diffraction of X-rays carried out almost a hundred years ago, numerous attempts have been made to determine structures of crystalline media from X-ray diffraction experiments. Usefulness of all of them has been limited by the inability of measuring phases of the diffracted beams. In this talk the most important researches carried out in this field will be reviewed and a recently obtained solution of the phase problem will be presented. Biography Emil Wolf is Wilson Professor of Optical Physics at the University of Rochester, and is reknowned for his work in physical optics. He has received many awards, including the Ives Medal of the Optical Society of America, the Albert A. -
Emil Wolf: ‘A Scientist and Friend Like No Other’ a Student of the Noted Physicist Counts up Some of His Mentor’S Contributions to Science and to His Colleagues
CLASS NOTES TRIBUTE Emil Wolf: ‘A Scientist and Friend Like No Other’ A student of the noted physicist counts up some of his mentor’s contributions to science and to his colleagues. Emil Wolf, the former Wilson Professor of Optical Physics, a In 1958, Robert Hopkins, then director of the institute, traveled faculty member in the University’s Institute of Optics and the to England for a conference and to meet with Emil. The meet- 1 3 Department of Physics and Astronomy, died in June at the age ing nearly didn’t happen. The letter from Hopkins got misfiled by of 95. He is survived by his children, Bruno and Paula, and his a secretary and was only discovered by Emil as he was searching beloved wife, Marlies. He was decorated with numerous presti- for another misfiled document. “It was all a matter of luck, par- gious national and international awards, honorary degrees, and ticularly that phone call in Paris at three in the morning saying appointments. He was my mentor and my friend and my measuring stick for what is good and what is decent. He was a refugee. When the Nazis in- vaded Czechoslovakia in 1939, Emil’s 2 brother, Karel, joined the Czech army. Emil was too young for the army and their parents sent him to Italy in hopes that he could somehow get to France or England. Trading valuable stamps his father had collected, Emil made his way from Prague to the Italian coast and then illegally into France by boat. Once in Paris, he found work with the Czech government in exile with whom he evacuated to Britain when Paris fell. -
Numerical Analysis of Focusing by a Metamaterial Lens
Numerical analysis of focusing by a metamaterial lens Ali Eren Culhaoglu1, Andrey Osipov1 and Peter Russer2 1 Microwaves and Radar Institute, German Aerospace Center 82234 Wessling Germany email: [email protected] 2 Institute for High Frequency Engineering, Technische Universitat¨ Munchen¨ Arcisstrasse 21, 80333 Munich Germany email: [email protected] Abstract Over the last several years there has been a surge of interest in artificial materials because of their potential to expand the range of electromagnetic properties in materials. The so called metamate- rials, also known as left-handed (LHM) or double-negative (DNG) materials with negative permittivity and permeability have attracted growing interest. An important application area is the realization of flat superlenses with imaging properties beyond that of conventional lenses. This work investigates the focusing properties of a lossless planar DNG slab with a relative permittivity and permeability both ap- proaching the value -1. The relation between the imaging quality and the material parameters is examined both analytically and numerically. Results obtained from numerical simulations via the transmission line matrix method are compared to the analytical solution. 1. Introduction Incident and emerging waves from a DNG slab will undergo negative refraction [1]. As a consequence p a slab with finite thickness d and material parameters "r = µr = -1 (refractive index n = "rµr = -1) focuses waves emitted from a point source located at a distance l in front of the slab to a point at a distance of d − l behind the slab [2, 3]. As seen in Fig. 1(a) the waves emitted from a point source are focused inside and outside the slab due to negative refraction at the slab interfaces. -
44. the Reality of Physical Optics at the Institute
AJC-05.qxd 21/06/04 11:38 AM Page 226 44. The Reality of Physical Optics at the Institute Brian J. Thompson The model that President Rush Rhees used in conjunction with his industrial counterparts and backers, George Eastman and Edward Bausch, for “his Institute” was the already suc- cessful Technical Optics Department at the Royal College of Science of the Imperial College of Science & Technology in London, England. Not only was this the model, but he hired the first two faculty members in England: Rudolf Kingslake, who had graduated from that Technical Optics Department in the second graduating class, for geometrical optics and A. Maurice Taylor for physical optics. These subjects were viewed as the two fundamental branches of the field so those of us who are working, or who have worked in the Institute in physical optics and developed that limb of the “optics tree” can trace our ancestry in part to 1929 and Maurice Taylor. He was a Ph.D. graduate from Cambridge University and co-author of a book, The Infrared Analysis of Molecular Structures, with F. I. G. Rawlins. While Kinglake had been appointed by the board of trustees in June of 1929, they didn’t act on Taylor’s appointment until November of 1929. The long and productive road from 1929 to 2003 has seen an explosion of under- standing, of new fundamental knowledge, and of diverse and interesting, and yes impor- tant, applications of physical optics. Maurice Taylor returned to England in 1934 and later became the chairman of the physics department at Southampton University. -
Astronomy 700: Radiation. 1 Basic Radiation Properties
Astronomy 700: Radiation. 1 Basic Radiation Properties 1.1 Basic definitions Fundamental importance to Astronomy: Almost exclusive carrier of information Radiation: Energy transport by electromagnetic fields Other forms of energy transport: cosmic rays • stochastic transport (micro: conduction, macro: convection) • gravitational waves • bulk transport (organized flows) • plasma waves • ... • Transport time variability (see section of E&M) → 1.1.1 The spectrum The most natural description of electromagnetic radiation is through Fourier decomposition into waves: f(~r, t) f(~k,ν) (1.1) ↔ where E is some variable describing the radiation field. Question: Why is this so natural? As we will shortly see, electromagnetic radiation naturally decomposes into waves with wave- length λ and frequency ν 1 Often, it is convenient to write the wave vector ~k =2πk/λˆ and angular frequency ω =2πν. In vacuum, group and phase velocity of those waves are equal: 10 1 λν = ∂ω/∂k c 2.99792... 10 cms− (1.2) ≡ ≡ × Fourier decomposition allows us to describe the local spectrum of the radiation at a fixed point in space as the Fourier transform ∞ f f(ν)= dtei2πνtf(t) (1.3) F ≡ Z−∞ and the inverse Fourier transform 1 ∞ i2πνt − f f(t)= dνe− f(ν) (1.4) F ≡ Z−∞ Without going into any details on Lebesque integration, it is worth pointing out the following identity: The inverse Fourier transform of a delta function in frequency is ∞ 1 i2πνt i2πν0t − δ(ν ν )= dνe− δ(ν ν )= e− (1.5) F − 0 − 0 Z−∞ i2πν0 t Thus, the Fourier transform of e− is ∞ i2πν0t i2π(ν ν0)t e− = dte − = δ(ν ν ) (1.6) F − 0 Z−∞ as one would expect for a decomposition into a spectrum of different exponentials.