Scientific and Related Works of Chen Ning Yang
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Submission from Jerry Cuttler
CMD 21-H4.22 File / dossier : 6.01.07 Date: 2021-05-03 Edocs: 6553919 Oral Presentation Exposé oral Written submission from Mémoire de Jerry Cuttler Jerry Cuttler In the Matter of the À l’égard de Darlington New Nuclear Project Projet de nouvelle centrale nucléaire de Darlington Application to renew the nuclear power Demande de renouvellement du permis de reactor site preparation licence for the préparation de l’emplacement d’une centrale Darlington New Nuclear Project nucléaire pour le projet de nouvelle centrale nucléaire de Darlington Commission Public Hearing Audience publique de la Commission June 10, 2021 10 juin 2021 Intervenor Report for CNSC Public Hearing by Dr. Jerry M. Cuttler, D.Sc., P.Eng. Vaughan, Ontario, Canada regarding Ontario Power Generation’s Application for renewal of its site preparation licence for the Darlington New Nuclear Project to be held June 10, 2021 Part A: Review of the licence renewal documents Part B: Evidence of beneficial effects of radiation and thresholds for detriment Intervenor written report Objective PFP contribution agreement PFP 2020 DNNP01 Cuttler, Section 2.2 requires: 1) participation in the proceedings of the Public Hearing on the OPG application to renew its site licence for the Darlington New Nuclear Project (DNNP), 2) review of the OPG licence renewal application and related documentation, including OPG and CNSC CMDs, and comment in its feasibility and safety aspects. The analysis must focus on OPG’s proposed site preparation licence. 3) submission of a written report summarizing comments from the review, 4) a presentation at the June 10, 2021 virtual Public Hearing. -
The Space Race
The Space Race Aims: To arrange the key events of the “Space Race” in chronological order. To decide which country won the Space Race. Space – the Final Frontier “Space” is everything Atmosphere that exists outside of our planet’s atmosphere. The atmosphere is the layer of Earth gas which surrounds our planet. Without it, none of us would be able to breathe! Space The sun is a star which is orbited (circled) by a system of planets. Earth is the third planet from the sun. There are nine planets in our solar system. How many of the other eight can you name? Neptune Saturn Mars Venus SUN Pluto Uranus Jupiter EARTH Mercury What has this got to do with the COLD WAR? Another element of the Cold War was the race to control the final frontier – outer space! Why do you think this would be so important? The Space Race was considered important because it showed the world which country had the best science, technology, and economic system. It would prove which country was the greatest of the superpowers, the USSR or the USA, and which political system was the best – communism or capitalism. https://www.youtube.com/watch?v=xvaEvCNZymo The Space Race – key events Discuss the following slides in your groups. For each slide, try to agree on: • which of the three options is correct • whether this was an achievement of the Soviet Union (USSR) or the Americans (USA). When did humans first send a satellite into orbit around the Earth? 1940s, 1950s or 1960s? Sputnik 1 was launched in October 1957. -
Why Antihydrogen and Antimatter Are Different As Paul Dirac Realized, the Existence of Antihydrogen Does Not in Itself Prove the Existence of Antimatter
ANTIMATTER Why antihydrogen and antimatter are different As Paul Dirac realized, the existence of antihydrogen does not in itself prove the existence of antimatter. A look through the history of the subject, and in particular the role played by the CPT theorem, shows that ultimately it came down to experiment to prove the existence of antimatter through the discovery of the antideuteron at CERN in 1965. “Those who say that antihydrogen is antimatter should realize that we are not made of hydrogen and we drink water, not liquid hydro- gen.” These are words spoken by Paul Dirac to physicists gathered around him after his lecture “My life as a Physicist” at the Ettore Majorana Foundation and Centre for Scientific Culture in Erice in 1981 – 53 years after he had, with a single equation, opened new horizons to human knowledge. To obtain water, hydrogen is, of course, not sufficient; oxygen with a nucleus of eight protons and eight neutrons is also needed. Hydrogen is the only element in the Periodic Table to consist of two charged particles (the electron and the proton) without any role being played by the nuclear forces. These two particles need only electromagnetic glue (the photon) to form the hydrogen atom. The antihydrogen atom needs t wo antipar- ticles (antiproton and antielectron) plus electromagnetic antiglue (antiphoton). Quantum electrodynamics (QED) dictates that the photon and the antiphoton are both eigenstates of the C-operator (see later) and therefore electromagnetic antiglue must exist and act like electromagnetic glue. Dirac surrounded by young physicists in Erice after his lecture “My Life If matter were made with hydrogen, the existence of antimatter as a Physicist”. -
Arxiv:1509.06955V1 [Physics.Optics]
Statistical mechanics models for multimode lasers and random lasers F. Antenucci 1,2, A. Crisanti2,3, M. Ib´a˜nez Berganza2,4, A. Marruzzo1,2, L. Leuzzi1,2∗ 1 NANOTEC-CNR, Institute of Nanotechnology, Soft and Living Matter Lab, Rome, Piazzale A. Moro 2, I-00185, Roma, Italy 2 Dipartimento di Fisica, Universit`adi Roma “Sapienza,” Piazzale A. Moro 2, I-00185, Roma, Italy 3 ISC-CNR, UOS Sapienza, Piazzale A. Moro 2, I-00185, Roma, Italy 4 INFN, Gruppo Collegato di Parma, via G.P. Usberti, 7/A - 43124, Parma, Italy We review recent statistical mechanical approaches to multimode laser theory. The theory has proved very effective to describe standard lasers. We refer of the mean field theory for passive mode locking and developments based on Monte Carlo simulations and cavity method to study the role of the frequency matching condition. The status for a complete theory of multimode lasing in open and disordered cavities is discussed and the derivation of the general statistical models in this framework is presented. When light is propagating in a disordered medium, the system can be analyzed via the replica method. For high degrees of disorder and nonlinearity, a glassy behavior is expected at the lasing threshold, providing a suggestive link between glasses and photonics. We describe in details the results for the general Hamiltonian model in mean field approximation and mention an available test for replica symmetry breaking from intensity spectra measurements. Finally, we summary some perspectives still opened for such approaches. The idea that the lasing threshold can be understood as a proper thermodynamic transition goes back since the early development of laser theory and non-linear optics in the 1970s, in particular in connection with modulation instability (see, e.g.,1 and the review2). -
The Physical Tourist Physics and New York City
Phys. perspect. 5 (2003) 87–121 © Birkha¨user Verlag, Basel, 2003 1422–6944/05/010087–35 The Physical Tourist Physics and New York City Benjamin Bederson* I discuss the contributions of physicists who have lived and worked in New York City within the context of the high schools, colleges, universities, and other institutions with which they were and are associated. I close with a walking tour of major sites of interest in Manhattan. Key words: Thomas A. Edison; Nikola Tesla; Michael I. Pupin; Hall of Fame for GreatAmericans;AlbertEinstein;OttoStern;HenryGoldman;J.RobertOppenheimer; Richard P. Feynman; Julian Schwinger; Isidor I. Rabi; Bronx High School of Science; StuyvesantHighSchool;TownsendHarrisHighSchool;NewYorkAcademyofSciences; Andrei Sakharov; Fordham University; Victor F. Hess; Cooper Union; Peter Cooper; City University of New York; City College; Brooklyn College; Melba Phillips; Hunter College; Rosalyn Yalow; Queens College; Lehman College; New York University; Courant Institute of Mathematical Sciences; Samuel F.B. Morse; John W. Draper; Columbia University; Polytechnic University; Manhattan Project; American Museum of Natural History; Rockefeller University; New York Public Library. Introduction When I was approached by the editors of Physics in Perspecti6e to prepare an article on New York City for The Physical Tourist section, I was happy to do so. I have been a New Yorker all my life, except for short-term stays elsewhere on sabbatical leaves and other visits. My professional life developed in New York, and I married and raised my family in New York and its environs. Accordingly, writing such an article seemed a natural thing to do. About halfway through its preparation, however, the attack on the World Trade Center took place. -
Conclusion: the Impact of Statistical Physics
Conclusion: The Impact of Statistical Physics Applications of Statistical Physics The different examples which we have treated in the present book have shown the role played by statistical mechanics in other branches of physics: as a theory of matter in its various forms it serves as a bridge between macroscopic physics, which is more descriptive and experimental, and microscopic physics, which aims at finding the principles on which our understanding of Nature is based. This bridge can be crossed fruitfully in both directions, to explain or predict macroscopic properties from our knowledge of microphysics, and inversely to consolidate the microscopic principles by exploring their more or less distant macroscopic consequences which may be checked experimentally. The use of statistical methods for deductive purposes becomes unavoidable as soon as the systems or the effects studied are no longer elementary. Statistical physics is a tool of common use in the other natural sciences. Astrophysics resorts to it for describing the various forms of matter existing in the Universe where densities are either too high or too low, and tempera tures too high, to enable us to carry out the appropriate laboratory studies. Chemical kinetics as well as chemical equilibria depend in an essential way on it. We have also seen that this makes it possible to calculate the mechan ical properties of fluids or of solids; these properties are postulated in the mechanics of continuous media. Even biophysics has recourse to it when it treats general properties or poorly organized systems. If we turn to the domain of practical applications it is clear that the technology of materials, a science aiming to develop substances which have definite mechanical (metallurgy, plastics, lubricants), chemical (corrosion), thermal (conduction or insulation), electrical (resistance, superconductivity), or optical (display by liquid crystals) properties, has a great interest in statis tical physics. -
Chapter 3 Bose-Einstein Condensation of an Ideal
Chapter 3 Bose-Einstein Condensation of An Ideal Gas An ideal gas consisting of non-interacting Bose particles is a ¯ctitious system since every realistic Bose gas shows some level of particle-particle interaction. Nevertheless, such a mathematical model provides the simplest example for the realization of Bose-Einstein condensation. This simple model, ¯rst studied by A. Einstein [1], correctly describes important basic properties of actual non-ideal (interacting) Bose gas. In particular, such basic concepts as BEC critical temperature Tc (or critical particle density nc), condensate fraction N0=N and the dimensionality issue will be obtained. 3.1 The ideal Bose gas in the canonical and grand canonical ensemble Suppose an ideal gas of non-interacting particles with ¯xed particle number N is trapped in a box with a volume V and at equilibrium temperature T . We assume a particle system somehow establishes an equilibrium temperature in spite of the absence of interaction. Such a system can be characterized by the thermodynamic partition function of canonical ensemble X Z = e¡¯ER ; (3.1) R where R stands for a macroscopic state of the gas and is uniquely speci¯ed by the occupa- tion number ni of each single particle state i: fn0; n1; ¢ ¢ ¢ ¢ ¢ ¢g. ¯ = 1=kBT is a temperature parameter. Then, the total energy of a macroscopic state R is given by only the kinetic energy: X ER = "ini; (3.2) i where "i is the eigen-energy of the single particle state i and the occupation number ni satis¯es the normalization condition X N = ni: (3.3) i 1 The probability -
Luis Alvarez: the Ideas Man
CERN Courier March 2012 Commemoration Luis Alvarez: the ideas man The years from the early 1950s to the late 1980s came alive again during a symposium to commemorate the birth of one of the great scientists and inventors of the 20th century. Luis Alvarez – one of the greatest experimental physicists of the 20th century – combined the interests of a scientist, an inventor, a detective and an explorer. He left his mark on areas that ranged from radar through to cosmic rays, nuclear physics, particle accel- erators, detectors and large-scale data analysis, as well as particles and astrophysics. On 19 November, some 200 people gathered at Berkeley to commemorate the 100th anniversary of his birth. Alumni of the Alvarez group – among them physicists, engineers, programmers and bubble-chamber film scanners – were joined by his collaborators, family, present-day students and admirers, as well as scientists whose professional lineage traces back to him. Hosted by the Lawrence Berkeley National Laboratory (LBNL) and the University of California at Berkeley, the symposium reviewed his long career and lasting legacy. A recurring theme of the symposium was, as one speaker put it, a “Shakespeare-type dilemma”: how could one person have accom- plished all of that in one lifetime? Beyond his own initiatives, Alvarez created a culture around him that inspired others to, as George Smoot put it, “think big,” as well as to “think broadly and then deep” and to take risks. Combined with Alvarez’s strong scientific standards and great care in execut- ing them, these principles led directly to the awarding of two Nobel Luis Alvarez celebrating the announcement of his 1968 Nobel prizes in physics to scientists at Berkeley – George Smoot in 2006 prize. -
Download This Article in PDF Format
The Second Lepton Family Klaus Winter, CERN The Nobel Prize for Physics for 1988 was awarded to L. Lederman, M. Schwartz and J. Steinberger for work on neutrinos in the early 1960s. In a letter [1] addressed to the "dear radioactive ladies and gentlemen", writ ten in December 1930, Wolfgang Pauli proposed, as a "desperate remedy" to save the principle of conservation of energy in beta-decay, the idea of the neutrino, a neutral particle of spin 1/2 and with a mass not larger than 0.01 proton mass. "The continuous beta-spectrum [2] would then become understandable by the assumption that in beta-decay a neutrino is emitted together with the electron, in such a way that the sum of the energies of the neutrino and electron is constant." Pauli did not specify at that time Fig. 1 — A recent photograph taken at CERN of Leon Lederman (left), whether the neutrino was to be ejected Jack Steinberger (centre) and Melvin Schwartz. or created. In his famous paper "An attempt of a theory of beta-decay" [3] the muon not decay into e + at the rate ween 1 and 2 GeV should be achievable. E. Fermi used the neutrino concept of predicted if such a non-locality exis Would these synchrotrons though, deli Pauli together with the concept of the ted ? ". On this view the muon would vir ver enough neutrinos? According to nucleon of Heisenberg. He assumed tually dissociate into W + v, the charged their specifications they should accele that in beta-decay a pair comprising an W would radiate a and W + v would rate 1011 protons per second, an unpre electron and a neutrino is created, analo recombine to an electron. -
Behaviour of Total and Elastic Cross-Sections at Very High Energies
CERN-TH.7437/94 9 OCR Output CERN—TH-7437-94 BEHAVIOUR OF TOTAL AND ELASTIC CROSS-SECTIONS AT VERY HIGH ENERGIES Tai '1`sun WU Gordon McKay Laboratory, Harvard University, Cambridge, MA 02138, USA and Theoretical Physics Division, CERN CH - 1211 Geneva 23 CERN-TH.7437/94 September 1994 BEHAVIOR OF TOTAL AND ELASTIC CROSS SECTIONS AT VERY HIGH ENERGIES TAI TSUN WU Gordon McKay Laboratory Harvard University Cambridge, MA 02138, USA, and Theoretical Physics Division, CERM Geneva, Switzerland 1. Introduction In this talk, I would like to present an overview of the original theoretical prediction of the increasing total cross section on the basis of gauge quantum field theory, phenomeno logical predictions from this theoretical understanding, comparison with later experimental data, and expected future data from HER.A. The discussion will be limited to elastic scattering, since it is the simplest scattering process. Through the optical theorem, the total cross section—which gives the overall strength of the scattering process———is proportional to the imaginary part of the elastic scattering amplitude in the forward direction. Therefore, the theoretical understanding of elastic scattering is often of primary importance. Some of these developments can be found in an excellent book by Herbert Fried, the organizer of this workshop: Herbert M. Fried, Fhnctional Methods and Eikonal Models, Editions Frontieres (1990). A few years earlier, Hung Cheng and I also wrote a book on this subject: Hung Cheng and Tai Tsun Wu, Expanding Protons: Scattering at High Energies, The MIT Press (1987). A recent topic of current interest, of course not covered in either of these books which are a few years old, is the data from the electron-proton colliding accelerator HQERA at DESY, Hamburg, Germany. -
Arxiv:2102.13616V2 [Cond-Mat.Quant-Gas] 30 Jul 2021 That Preserve Stability of the Underlying Problem1
Self-stabilized Bose polarons Richard Schmidt1, 2 and Tilman Enss3 1Max-Planck-Institute of Quantum Optics, Hans-Kopfermann-Straße 1, 85748 Garching, Germany 2Munich Center for Quantum Science and Technology, Schellingstraße 4, 80799 Munich, Germany 3Institut f¨urTheoretische Physik, Universit¨atHeidelberg, 69120 Heidelberg, Germany (Dated: August 2, 2021) The mobile impurity in a Bose-Einstein condensate (BEC) is a paradigmatic many-body problem. For weak interaction between the impurity and the BEC, the impurity deforms the BEC only slightly and it is well described within the Fr¨ohlich model and the Bogoliubov approximation. For strong local attraction this standard approach, however, fails to balance the local attraction with the weak repulsion between the BEC particles and predicts an instability where an infinite number of bosons is attracted toward the impurity. Here we present a solution of the Bose polaron problem beyond the Bogoliubov approximation which includes the local repulsion between bosons and thereby stabilizes the Bose polaron even near and beyond the scattering resonance. We show that the Bose polaron energy remains bounded from below across the resonance and the size of the polaron dressing cloud stays finite. Our results demonstrate how the dressing cloud replaces the attractive impurity potential with an effective many-body potential that excludes binding. We find that at resonance, including the effects of boson repulsion, the polaron energy depends universally on the effective range. Moreover, while the impurity contact is strongly peaked at positive scattering length, it remains always finite. Our solution highlights how Bose polarons are self-stabilized by repulsion, providing a mechanism to understand quench dynamics and nonequilibrium time evolution at strong coupling. -
Is It the First Use of the Word Astrobiology ? Author
Title : Is it the first use of the word Astrobiology ? Author : Danielle Briot Adress : Observatoire de Paris 61 avenue de l’Observatoire 75014 Paris France tel : 33(0)1 40 51 22 39 and 33(0)1 45 07 78 57 [email protected] running title : First use of the word Astrobiology ? 1 Abstract The research of life in Universe is a ancient quest that has taken different forms over the centuries. It has given rise to a new science, which is normally referred as Astrobiology. It is interesting to research when this word was used for the first time and when this science developed to represent the search for life in Universe as is done today. There are records of the usage of the word "Astrobiology" as early as 1935, in an article published in a French popular science magazine. Moreover this article is quite remarkable because its portrayal of the concept of the subject is very similar to that considered today. The author of this paper was Ary J. Sternfeld (1905 - 1980), who was ortherwise known as a poorly respected great pioneer of astronautics. We provide a brief description of his life, which was heavily influenced by the tragic events of the 20th century history, from Poland and France to Russia. He was a prolific scientific writer who wrote a number of very successful scientific books and papers. Keywords : History – Pioneers 2 1. Introduction The question of the life in the Universe, in relation with the question of the multiplicity of worlds, is very ancient and probably dates back to Greek philosophers.