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Thesis Reference
Thesis On Testing Modified Gravity : with Solar System Experiments and Gravitational Radiation SANCTUARY, Hillary Adrienne Abstract Three theories of gravitation – general relativity, the chameleon and Horava gravity - are confronted with experiment, using standard and adapted post-Newtonian (PN) tools. The laboratory is provided by the Solar System, binary pulsars and future detections at gravitational wave observatories. We test Horava gravity by studying emission of gravitational radiation in the weak-field limit for PN sources using techniques that take full advantage of the parametrized post-Newtonian (PPN) formalism. In particular, we provide a generalization of Einstein’s quadrupole formula and show that a monopole persists even in the limit in which the PPN parameters are identical to those of General Relativity. Based on a technique called non-relativistic General Relativity, we propose a phenomenological way to measure deviations from General Relativity coming from an unknown UV completion. Finally, we systematically show that the self-interacting chameleon at orders three and higher do not jeopardize the chameleon theory for Solar System type objects. Reference SANCTUARY, Hillary Adrienne. On Testing Modified Gravity : with Solar System Experiments and Gravitational Radiation. Thèse de doctorat : Univ. Genève, 2012, no. Sc. 4524 Available at: http://archive-ouverte.unige.ch/unige:28935 Disclaimer: layout of this document may differ from the published version. [ Downloaded 07/04/2015 at 08:06:08 ] 1 / 1 UNIVERSITÉ DE GENÈVE FACULTÉ DES SCIENCES Département de physique théorique Professeur Michele Maggiore On Testing Modified Gravity with Solar System Experiments and Gravitational Radiation THÈSE présentée à la Faculté des Sciences de l’Université de Genève pour obtenir le grade de Docteur ès Sciences, mention Physique par Hillary Sanctuary de Montréal, Canada Thèse No 4524 Genève, juillet 2012 Reprographie EPFL Publications D. -
Advanced Information on the Nobel Prize in Physics, 5 October 2004
Advanced information on the Nobel Prize in Physics, 5 October 2004 Information Department, P.O. Box 50005, SE-104 05 Stockholm, Sweden Phone: +46 8 673 95 00, Fax: +46 8 15 56 70, E-mail: [email protected], Website: www.kva.se Asymptotic Freedom and Quantum ChromoDynamics: the Key to the Understanding of the Strong Nuclear Forces The Basic Forces in Nature We know of two fundamental forces on the macroscopic scale that we experience in daily life: the gravitational force that binds our solar system together and keeps us on earth, and the electromagnetic force between electrically charged objects. Both are mediated over a distance and the force is proportional to the inverse square of the distance between the objects. Isaac Newton described the gravitational force in his Principia in 1687, and in 1915 Albert Einstein (Nobel Prize, 1921 for the photoelectric effect) presented his General Theory of Relativity for the gravitational force, which generalized Newton’s theory. Einstein’s theory is perhaps the greatest achievement in the history of science and the most celebrated one. The laws for the electromagnetic force were formulated by James Clark Maxwell in 1873, also a great leap forward in human endeavour. With the advent of quantum mechanics in the first decades of the 20th century it was realized that the electromagnetic field, including light, is quantized and can be seen as a stream of particles, photons. In this picture, the electromagnetic force can be thought of as a bombardment of photons, as when one object is thrown to another to transmit a force. -
Renormalization Group - Wikipedia, the Free Encyclopedia 3/17/12 5:27 PM Renormalization Group from Wikipedia, the Free Encyclopedia
Renormalization group - Wikipedia, the free encyclopedia 3/17/12 5:27 PM Renormalization group From Wikipedia, the free encyclopedia In theoretical physics, the renormalization group (RG) refers to a mathematical apparatus that allows systematic investigation of the changes of a physical system as viewed at different distance scales. In particle physics, it reflects the changes in the underlying force laws (codified in a quantum field theory) as the energy scale at which physical processes occur varies, energy/momentum and resolution distance scales being effectively conjugate under the uncertainty principle (cf. Compton wavelength). A change in scale is called a "scale transformation". The renormalization group is intimately related to "scale invariance" and "conformal invariance", symmetries in which a system appears the same at all scales (so-called self-similarity). (However, note that scale transformations are included in conformal transformations, in general: the latter including additional symmetry generators associated with special conformal transformations.) As the scale varies, it is as if one is changing the magnifying power of a notional microscope viewing the system. In so- called renormalizable theories, the system at one scale will generally be seen to consist of self-similar copies of itself when viewed at a smaller scale, with different parameters describing the components of the system. The components, or fundamental variables, may relate to atoms, elementary particles, atomic spins, etc. The parameters of the theory typically describe the interactions of the components. These may be variable "couplings" which measure the strength of various forces, or mass parameters themselves. The components themselves may appear to be composed of more of the self-same components as one goes to shorter distances. -
Lecture 9 CPT Theorem and CP Violation
Lecture 9 CPT theorem and CP violation Emmy Noether's theorem (proved 1915, published 1918) •Any differentiable symmetry of the action of a physical system has a corresponding conservation law. The action of a physical system is the integral over time of a Lagrangian function (which may or may not be an integral over space of a Lagrangian density function), from which the system’s behavior can be determined by the principle of least action. •Energy, momentum and angular momentum conservation laws are consequences of symmetries of space. eg, if a physical system behaves the same regardless of how it is oriented in space -> Lagrangian is rotationally symmetric -> angular momentum of the system must be conserved •We have seen that although both charge conjugation and parity are violated in weak interactions, the combination of the two CP turns left-handed antimuon onto right-handed muon, that is exactly observed in nature. •There is another symmetry in nature – time reversal T (winding the film backward). •Charge conjugation, C, together with parity inversion, P, and time reversal, T, are connected into the famous CPT theorem. •CPT theorem is one of the basic principles of quantum field theory. It states that all interactions are invariant under sequential application of C, P and T operations in any order. Any Lorentz invariant local quantum field theory with a Hermitian Hamiltonian must have CPT symmetry. •It is closely related to the interpretation that antiparticles can be treated mathematically as particles moving backward in time. Ernst Stueckelberg (1905-1984) Should have received several Noble prizes • 1934 - First developer of fully Lorentz-covariant theory for quantum field • 1935 - Developed vector boson exchange as theoretical explanation for nuclear forces. -
Arxiv:1403.5164V1 [Physics.Hist-Ph] 20 Mar 2014
The education of Walter Kohn and the creation of density functional theory Andrew Zangwill∗ School of Physics Georgia Institute of Technology Atlanta, GA 30332 The theoretical solid-state physicist Walter Kohn was awarded one-half of the 1998 Nobel Prize in Chemistry for his mid-1960’s creation of an approach to the many-particle problem in quantum mechanics called density functional theory (DFT). In its exact form, DFT establishes that the total charge density of any system of electrons and nuclei provides all the information needed for a complete description of that system. This was a breakthrough for the study of atoms, molecules, gases, liquids, and solids. Before DFT, it was thought that only the vastly more complicated many-electron wave function was needed for a complete description of such systems. Today, fifty years after its introduction, DFT (in one of its approximate forms) is the method of choice used by most scientists to calculate the physical properties of materials of all kinds. In this paper, I present a biographical essay of Kohn’s educational experiences and professional career up to and including the creation of DFT. My account begins with Kohn’s student years in Austria, England, and Canada during World War II and continues with his graduate and post-graduate training at Harvard University and Niels Bohr’s Institute for Theoretical Physics in Copenhagen. I then study the research choices he made during the first ten years of his career (when he was a faculty member at the Carnegie Institute of Technology and a frequent visitor to the Bell Telephone Laboratories) in the context of the theoretical solid-state physics agenda of the late 1950’s and early 1960’s. -
Constructive Quantum Field Theory : Goals, Methods, Results
Constructive quantum field theory : goals, methods, results Autor(en): Osterwalder, K. Objekttyp: Article Zeitschrift: Helvetica Physica Acta Band (Jahr): 59 (1986) Heft 2 PDF erstellt am: 09.10.2021 Persistenter Link: http://doi.org/10.5169/seals-115691 Nutzungsbedingungen Die ETH-Bibliothek ist Anbieterin der digitalisierten Zeitschriften. Sie besitzt keine Urheberrechte an den Inhalten der Zeitschriften. Die Rechte liegen in der Regel bei den Herausgebern. Die auf der Plattform e-periodica veröffentlichten Dokumente stehen für nicht-kommerzielle Zwecke in Lehre und Forschung sowie für die private Nutzung frei zur Verfügung. Einzelne Dateien oder Ausdrucke aus diesem Angebot können zusammen mit diesen Nutzungsbedingungen und den korrekten Herkunftsbezeichnungen weitergegeben werden. Das Veröffentlichen von Bildern in Print- und Online-Publikationen ist nur mit vorheriger Genehmigung der Rechteinhaber erlaubt. Die systematische Speicherung von Teilen des elektronischen Angebots auf anderen Servern bedarf ebenfalls des schriftlichen Einverständnisses der Rechteinhaber. Haftungsausschluss Alle Angaben erfolgen ohne Gewähr für Vollständigkeit oder Richtigkeit. Es wird keine Haftung übernommen für Schäden durch die Verwendung von Informationen aus diesem Online-Angebot oder durch das Fehlen von Informationen. Dies gilt auch für Inhalte Dritter, die über dieses Angebot zugänglich sind. Ein Dienst der ETH-Bibliothek ETH Zürich, Rämistrasse 101, 8092 Zürich, Schweiz, www.library.ethz.ch http://www.e-periodica.ch Helvetica Physica Acta, Vol. -
Dirac: a Scientific Biography in Geneva, Bringing His Wife and Two Children with Him
Dirac A SCIENTIFIC BIOGRAPHY HELGE KRAGH CAMBRIDGE UNIVERSITY PRESS Published by the Press Syndic:a1e or the Uaiversity ol Cambridge The Pin Building, Tru~ton Streec, Cambridge CB2 1RP 40 West200l Slrl:el, New York. NY 10011-4211. USA 10 Stamford Road, Oakleigh, Victoria 3166, Australia 0 Cambridge Uaiversity Press 1990 First published 1990 Reprinted 1991, 1992 Printed in the Uaited Stales of America Ubrary of Congress Clllaloging-in-Publiwtion Data Kragh, Helge, 1944- Dirac : a scientific biography I He1ge Kragh. P. em. Bibliography: p. Includes indexes. ISBN M21-38089-8 I. Dirac, P. A.M. (Paul AdrieD Maurice), 1902- 2. Physicists- Great Britaia - Biography. I. Tille. DCI6.051K73 1990 530'.092- dc20 [B) 89-17257 CIP ISBN 0.521-38089-8 hardback TO BODIL CONTENTS Preface page lX I. Early years 2. Discovery of quantum mechanics 14 3. Relativity and spinning electrons 48 4. Travels and thinking 67 5. The dream of philosophers 87 6. Quanta and fields 118 7. Fifty years of a physicist's life 151 8. ''The so-called quantum electrodynamics" 165 9. Electrons and ether 189 10. Just a disappointment 205 II. Adventures in cosmology 223 12. The purest soul 247 13. Philosophy in physics 260 14. The principle of mathematical beauty 275 Appendix I. Dirac bibliometrics 293 Appendix II. Bibliography of P. A. M. Dirac 304 Notes and references 315 General bibliography 364 Index of names 383 Index ofsubjects 387 vii PREFACE NE of the greatest physicists who ever lived, P. A. M. Dirac 0 ( 1902-84) made contributions that may well be compared with those of other, better known giants of science such as Newton, Maxwell, Einstein, and Bohr. -
Quantum Field Theory in a Nutshell Ebook
QUANTUM FIELD THEORY IN A NUTSHELL PDF, EPUB, EBOOK Anthony Zee | 608 pages | 01 Apr 2010 | Princeton University Press | 9780691140346 | English | New Jersey, United States Quantum Field Theory in a Nutshell PDF Book Every term in the expansion may be understood as one possible way for physical particles to interact with each other via virtual particles, expressed visually using a Feynman diagram. Create a video. This was my mistake for not reading the blueprint though. View 1 comment. Even if the theory were very complicated at that scale, as long as its couplings are sufficiently weak, it must be described at low energies by a renormalisable effective field theory. Some focused on symmetry principles and conservation laws , while others picked up the old S-matrix theory of Wheeler and Heisenberg. In an exchange of letters with Richard Bentley , however, Newton stated that "it is inconceivable that inanimate brute matter should, without the mediation of something else which is not material, operate upon and affect other matter without mutual contact. Nuclear Physics in a Nutshell Carlos A. Among the four fundamental interactions, gravity remains the only one that lacks a consistent QFT description. Dan Mat Fys Medd. Contrary to this optimism, QFT entered yet another period of depression that lasted for almost two decades. Physical Review. Physica Scripta. A different approach, called renormalised perturbation theory, is to use physically meaningful quantities from the very beginning. Bet you don't know what a path integral is either. Return to Book Page. Components that are totally disconnected from external lines are sometimes called "vacuum bubbles". -
Hundred Years of Electron in Physics
HUNDRED YEARS OF ELECTRON IN PHYSICS Helmut Rechenberg Max Planck Institute f¨ur Physik (Werner-Heisenberg-Institut) F¨ohringer Ring 6, D-80805 Munich, Germany I. Introduction I.1 The discovery of the electron (1897) [1] The idea of a smallest electrically charged particle was fairly common among the physicists of the 19th century, though it became quite pushed into the background, when James Clerk Maxwell’s field-theoretical electrodynamics defeated after 1870 the competing particle with the action-at-a-distance theories of Wilhelm Weber, Rudolf Clausius and others. Still the concept survived: Thus Hermann von Helmholtz emphasized in his 1881 Faraday Lecture the possibility of an ‘atom of electricity’, and the Dutch theoretician Hendrik Antoon Lorentz – starting from a theory of diffraction of light (PhD thesis 1875) – developed in the 1890s an electrodynamics of moving (charged) bodies based on the existence of what the Irish physicist George Johnstone Stoney baptized in 1891 the ‘electron’. The true discovery of the electron then happened six years later, in connection with an analysis of two different sets of phenomena. The first approach emerged from the detailed study of cathode rays. Though they were found already in 1858 by Julius Pl¨ucker, physicist still debated their nature in the 1890s – thus Cromwell F. Varley and William Crookes in England preferred a particle explanation, while Heinrich Hertz in Germany argued against this (since his experiments revealed no influence of electric fields). When Hertz’s assistant Philipp Lenard succeeded to obtain in 1893 cathode rays in a discharge-free space (through a thin metallic foil, the ‘Lenard window’), a new experimental epoch began. -
Further Questions for Glashow Goran Senjanović, Reply by Sheldon Lee Glashow
INFERENCE / Vol. 5, No. 3 Further Questions for Glashow Goran Senjanović, reply by Sheldon Lee Glashow In response to “The Yang–Mills Model” (Vol. 5, No. 2). of our field, and even more surprised that Glashow men- tions this only in passing. It is already mind-boggling that George Zweig and James Bjorken never got the Nobel Prize To the editors: for their seminal works; after all, Makoto Kobayashi and Toshihide Maskawa got it for predicting more of the same. It is an honor and a pleasure to comment on Sheldon Lee Now it seems that Petermann should also be included. It Glashow’s magisterial essay on the Yang–Mills model. would be nice to know more about that. His essay is all the more special for describing one of the Glashow remarks that Yang–Mills symmetry is natu- greatest chapters in the history of physics, the story of a rally there in the string picture. It is hard to understand beautiful mathematical concept transformed into a theory why that matters. Should we appreciate Yang–Mills theory for all seasons, the Standard Model of particle physics. It more because of that? Or should we appreciate the strings was of course Glashow who played a central role in the more? Presumably the latter, since the Yang–Mills theory electroweak part of the story by coming up with his mas- is at the core of high-energy physics, while strings are a terpiece, the SU(2) × U(1) gauge theory. And with the added wild speculation, to this day phenomenologically unjusti- masterstroke from Steven Weinberg, his high-school fied. -
Quantum Field Theory in a Nutshell Free
FREE QUANTUM FIELD THEORY IN A NUTSHELL PDF Anthony Zee | 608 pages | 01 Apr 2010 | Princeton University Press | 9780691140346 | English | New Jersey, United States In a Nutshell | Princeton University Press In theoretical physicsquantum field theory QFT is a theoretical framework that combines classical field theoryspecial relativity and quantum mechanics [1] : xibut not general relativity 's description of gravity. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles. QFT treats particles as excited states also called quanta of their underlying fieldswhich are more fundamental than the particles. Interactions between particles are described by interaction terms in the Lagrangian involving their corresponding fields. Each interaction can be visually represented by Feynman diagrams according to perturbation theory in quantum mechanics. As a successful theoretical framework today, quantum field theory emerged from the work of generations of theoretical physicists spanning much of the 20th century. Its development began in the s with the description of interactions between light and electronsculminating in the first quantum field theory— quantum electrodynamics. A major theoretical obstacle soon followed with the appearance and persistence of various infinities in perturbative calculations, a problem only resolved in the s with the invention of the renormalization procedure. A second major barrier came with QFT's apparent inability to describe the weak and strong interactionsto the point where some theorists called for the abandonment of the field theoretic approach. The development of gauge theory and the completion of the Standard Model in the s led to a renaissance of quantum field theory. -
Cern Courier May/June 2019 3
CERNMay/June 2019 cerncourier.com COURIERReporting on international high-energy physics WELCOME CERN Courier – digital edition PERSPECTIVES ON THE Welcome to the digital edition of the May/June 2019 issue of CERN Courier. PROTON It is 100 years since Ernest Rutherford published his results proving the existence of the proton. For many decades the proton was considered elementary. But ever since experiments at SLAC and DESY started firing electrons into protons, beginning in the 1960s, deep-inelastic-scattering experiments have revealed a complex internal picture. In this issue we take an expert tour of physicists’ evolving understanding of the proton, and find that there is still much to learn about this ubiquitous particle – including the origin of its spin, whether or not it decays and the puzzling value of its radius. Flavour physics is another theme of the issue. LHCb’s observation of CP violation in the charm sector represents a milestone result, and the collaboration recently released an update of the ratio RK concerning the ratio of certain B-meson decays. From a theoretical perspective, new gauge bosons and leptoquarks are promising potential explanations for the current anomalies reported in the b-quark system, although the picture is far from clear and more data are needed. Meanwhile, researchers are also searching for ultra-rare muon decays that violate lepton-number conservation. Also in this issue: LHCb’s discovery of a new pentaquark, DESY’s astroparticle ambitions, news on the International Linear Collider, the first image of the centre of a galaxy, and more. To sign up to the new-issue alert, please visit: http://cerncourier.com/cws/sign-up.