Memories of a Theoretical Physicist
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Unrestricted Immigration and the Foreign Dominance Of
Unrestricted Immigration and the Foreign Dominance of United States Nobel Prize Winners in Science: Irrefutable Data and Exemplary Family Narratives—Backup Data and Information Andrew A. Beveridge, Queens and Graduate Center CUNY and Social Explorer, Inc. Lynn Caporale, Strategic Scientific Advisor and Author The following slides were presented at the recent meeting of the American Association for the Advancement of Science. This project and paper is an outgrowth of that session, and will combine qualitative data on Nobel Prize Winners family histories along with analyses of the pattern of Nobel Winners. The first set of slides show some of the patterns so far found, and will be augmented for the formal paper. The second set of slides shows some examples of the Nobel families. The authors a developing a systematic data base of Nobel Winners (mainly US), their careers and their family histories. This turned out to be much more challenging than expected, since many winners do not emphasize their family origins in their own biographies or autobiographies or other commentary. Dr. Caporale has reached out to some laureates or their families to elicit that information. We plan to systematically compare the laureates to the population in the US at large, including immigrants and non‐immigrants at various periods. Outline of Presentation • A preliminary examination of the 609 Nobel Prize Winners, 291 of whom were at an American Institution when they received the Nobel in physics, chemistry or physiology and medicine • Will look at patterns of -
Frank Wilczek on the World's Numerical Recipe
Note by All too often, we ignore goals, genres, or Frank Wilczek values, or we assume that they are so apparent that we do not bother to high- light them. Yet judgments about whether an exercise–a paper, a project, an essay Frank Wilczek response on an examination–has been done intelligently or stupidly are often on the dif½cult for students to fathom. And since these evaluations are not well world’s understood, few if any lessons can be numerical drawn from them. Laying out the criteria recipe by which judgments of quality are made may not suf½ce in itself to improve qual- ity, but in the absence of such clari½- cation, we have little reason to expect our students to go about their work intelligently. Twentieth-century physics began around 600 b.c. when Pythagoras of Samos pro- claimed an awesome vision. By studying the notes sounded by plucked strings, Pythagoras discovered that the human perception of harmony is connected to numerical ratios. He examined strings made of the same material, having the same thickness, and under the same tension, but of different lengths. Under these conditions, he found that the notes sound harmonious precisely when the ratio of the lengths of string can be expressed in small whole numbers. For example, the length ratio Frank Wilczek, Herman Feshbach Professor of Physics at MIT, is known, among other things, for the discovery of asymptotic freedom, the develop- ment of quantum chromodynamics, the invention of axions, and the discovery and exploitation of new forms of quantum statistics (anyons). -
3-Fermion Topological Quantum Computation [1]
3-Fermion topological quantum computation [1] Sam Roberts1 and Dominic J. Williamson2 1Centre for Engineered Quantum Systems, School of Physics, The University of Sydney, Sydney, NSW 2006, Australia 2Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305, USA I. INTRODUCTION Topological quantum computation (TQC) is currently the most promising approach to scalable, fault-tolerant quantum computation. In recent years, the focus has been on TQC with Kitaev's toric code [2], due to it's high threshold to noise [3, 4], and amenability to planar architectures with nearest neighbour interactions. To encode and manipulate quantum information in the toric code, a variety of techniques drawn from condensed matter contexts have been utilised. In particular, some of the efficient approaches for TQC with the toric code rely on creating and manipulating gapped-boundaries, symmetry defects and anyons of the underlying topological phase of matter [5{ 10]. Despite great advances, the overheads for universal fault-tolerant quantum computation remain a formidable challenge. It is therefore important to analyse the potential of TQC in a broad range of topological phases of matter, and attempt to find new computational substrates that require fewer quantum resources to execute fault-tolerant quantum computation. In this work we present an approach to TQC for more general anyon theories based on the Walker{Wang mod- els [11]. This provides a rich class of spin-lattice models in three-dimensions whose boundaries can naturally be used to topologically encode quantum information. The two-dimensional boundary phases of Walker{Wang models accommodate a richer set of possibilities than stand-alone two-dimensional topological phases realized by commuting projector codes [12, 13]. -
String Theory. Volume 1, Introduction to the Bosonic String
This page intentionally left blank String Theory, An Introduction to the Bosonic String The two volumes that comprise String Theory provide an up-to-date, comprehensive, and pedagogic introduction to string theory. Volume I, An Introduction to the Bosonic String, provides a thorough introduction to the bosonic string, based on the Polyakov path integral and conformal field theory. The first four chapters introduce the central ideas of string theory, the tools of conformal field theory and of the Polyakov path integral, and the covariant quantization of the string. The next three chapters treat string interactions: the general formalism, and detailed treatments of the tree-level and one loop amplitudes. Chapter eight covers toroidal compactification and many important aspects of string physics, such as T-duality and D-branes. Chapter nine treats higher-order amplitudes, including an analysis of the finiteness and unitarity, and various nonperturbative ideas. An appendix giving a short course on path integral methods is also included. Volume II, Superstring Theory and Beyond, begins with an introduction to supersym- metric string theories and goes on to a broad presentation of the important advances of recent years. The first three chapters introduce the type I, type II, and heterotic superstring theories and their interactions. The next two chapters present important recent discoveries about strongly coupled strings, beginning with a detailed treatment of D-branes and their dynamics, and covering string duality, M-theory, and black hole entropy. A following chapter collects many classic results in conformal field theory. The final four chapters are concerned with four-dimensional string theories, and have two goals: to show how some of the simplest string models connect with previous ideas for unifying the Standard Model; and to collect many important and beautiful general results on world-sheet and spacetime symmetries. -
Supergravity and Its Legacy Prelude and the Play
Supergravity and its Legacy Prelude and the Play Sergio FERRARA (CERN – LNF INFN) Celebrating Supegravity at 40 CERN, June 24 2016 S. Ferrara - CERN, 2016 1 Supergravity as carved on the Iconic Wall at the «Simons Center for Geometry and Physics», Stony Brook S. Ferrara - CERN, 2016 2 Prelude S. Ferrara - CERN, 2016 3 In the early 1970s I was a staff member at the Frascati National Laboratories of CNEN (then the National Nuclear Energy Agency), and with my colleagues Aurelio Grillo and Giorgio Parisi we were investigating, under the leadership of Raoul Gatto (later Professor at the University of Geneva) the consequences of the application of “Conformal Invariance” to Quantum Field Theory (QFT), stimulated by the ongoing Experiments at SLAC where an unexpected Bjorken Scaling was observed in inclusive electron- proton Cross sections, which was suggesting a larger space-time symmetry in processes dominated by short distance physics. In parallel with Alexander Polyakov, at the time in the Soviet Union, we formulated in those days Conformal invariant Operator Product Expansions (OPE) and proposed the “Conformal Bootstrap” as a non-perturbative approach to QFT. S. Ferrara - CERN, 2016 4 Conformal Invariance, OPEs and Conformal Bootstrap has become again a fashionable subject in recent times, because of the introduction of efficient new methods to solve the “Bootstrap Equations” (Riccardo Rattazzi, Slava Rychkov, Erik Tonni, Alessandro Vichi), and mostly because of their role in the AdS/CFT correspondence. The latter, pioneered by Juan Maldacena, Edward Witten, Steve Gubser, Igor Klebanov and Polyakov, can be regarded, to some extent, as one of the great legacies of higher dimensional Supergravity. -
April Meeting Goes Mile-High in 2004 Highlights New Techniques For
January 2004 Volume 13, No. 1 NEWS http://www.physics2005.org A Publication of The American Physical Society http://www.aps.org/apsnews April Meeting Goes Junior Members Respond to Mile-High in 2004 APS Ethics Survey By Ernie Tretkoff The “Mile High” city of Denver, International Affairs, Colorado, will host as many as History of Physics, and Few physicists received for- to include not just research mis- 1500 physicists at the 2004 APS Graduate Student Af- mal ethics training as part of their conduct such as data fabrication, April meeting, to be held May 1-4 fairs; and the Topical education, though many are con- falsification, and plagiarism, but 2004. Groups on Few-Body cerned about professional ethics, also issues such as authorship, Attendees will be drawn from a Systems, Precision a study by the APS Ethics Task proper credit of previous work, wide range of research areas. APS Measurement and Force has found. and data handling and reporting. units represented at the meeting Fundamental Con- Photo Credit: The Denver Metro Convention and Visitors Bureau The task force report was sub- “This was an interesting and include the Divisions of Astrophys- stants, Gravitation, Denver has the 10th largest downtown in America. mitted to and accepted by the sobering project,” said task force ics, Nuclear Physics, Particles and Plasma Astrophysics, APS Council at its meeting in chair Frances Houle of the IBM Fields, Plasma Physics, and Com- and Hadronic Physics. approximately 45 invited sessions. November. Almaden Research Center in San putational Physics; the Forums on The scientific program will fea- There will also be numerous con- The task force, which was con- Jose. -
Stephen Hawking: 'There Are No Black Holes' Notion of an 'Event Horizon', from Which Nothing Can Escape, Is Incompatible with Quantum Theory, Physicist Claims
NATURE | NEWS Stephen Hawking: 'There are no black holes' Notion of an 'event horizon', from which nothing can escape, is incompatible with quantum theory, physicist claims. Zeeya Merali 24 January 2014 Artist's impression VICTOR HABBICK VISIONS/SPL/Getty The defining characteristic of a black hole may have to give, if the two pillars of modern physics — general relativity and quantum theory — are both correct. Most physicists foolhardy enough to write a paper claiming that “there are no black holes” — at least not in the sense we usually imagine — would probably be dismissed as cranks. But when the call to redefine these cosmic crunchers comes from Stephen Hawking, it’s worth taking notice. In a paper posted online, the physicist, based at the University of Cambridge, UK, and one of the creators of modern black-hole theory, does away with the notion of an event horizon, the invisible boundary thought to shroud every black hole, beyond which nothing, not even light, can escape. In its stead, Hawking’s radical proposal is a much more benign “apparent horizon”, “There is no escape from which only temporarily holds matter and energy prisoner before eventually a black hole in classical releasing them, albeit in a more garbled form. theory, but quantum theory enables energy “There is no escape from a black hole in classical theory,” Hawking told Nature. Peter van den Berg/Photoshot and information to Quantum theory, however, “enables energy and information to escape from a escape.” black hole”. A full explanation of the process, the physicist admits, would require a theory that successfully merges gravity with the other fundamental forces of nature. -
FIELDS MEDAL for Mathematical Efforts R
Recognizing the Real and the Potential: FIELDS MEDAL for Mathematical Efforts R Fields Medal recipients since inception Year Winners 1936 Lars Valerian Ahlfors (Harvard University) (April 18, 1907 – October 11, 1996) Jesse Douglas (Massachusetts Institute of Technology) (July 3, 1897 – September 7, 1965) 1950 Atle Selberg (Institute for Advanced Study, Princeton) (June 14, 1917 – August 6, 2007) 1954 Kunihiko Kodaira (Princeton University) (March 16, 1915 – July 26, 1997) 1962 John Willard Milnor (Princeton University) (born February 20, 1931) The Fields Medal 1966 Paul Joseph Cohen (Stanford University) (April 2, 1934 – March 23, 2007) Stephen Smale (University of California, Berkeley) (born July 15, 1930) is awarded 1970 Heisuke Hironaka (Harvard University) (born April 9, 1931) every four years 1974 David Bryant Mumford (Harvard University) (born June 11, 1937) 1978 Charles Louis Fefferman (Princeton University) (born April 18, 1949) on the occasion of the Daniel G. Quillen (Massachusetts Institute of Technology) (June 22, 1940 – April 30, 2011) International Congress 1982 William P. Thurston (Princeton University) (October 30, 1946 – August 21, 2012) Shing-Tung Yau (Institute for Advanced Study, Princeton) (born April 4, 1949) of Mathematicians 1986 Gerd Faltings (Princeton University) (born July 28, 1954) to recognize Michael Freedman (University of California, San Diego) (born April 21, 1951) 1990 Vaughan Jones (University of California, Berkeley) (born December 31, 1952) outstanding Edward Witten (Institute for Advanced Study, -
Arxiv:1705.01740V1 [Cond-Mat.Str-El] 4 May 2017 2
Physics of the Kitaev model: fractionalization, dynamical correlations, and material connections M. Hermanns1, I. Kimchi2, J. Knolle3 1Institute for Theoretical Physics, University of Cologne, 50937 Cologne, Germany 2Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA and 3T.C.M. group, Cavendish Laboratory, J. J. Thomson Avenue, Cambridge, CB3 0HE, United Kingdom Quantum spin liquids have fascinated condensed matter physicists for decades because of their unusual properties such as spin fractionalization and long-range entanglement. Unlike conventional symmetry breaking the topological order underlying quantum spin liquids is hard to detect exper- imentally. Even theoretical models are scarce for which the ground state is established to be a quantum spin liquid. The Kitaev honeycomb model and its generalizations to other tri-coordinated lattices are chief counterexamples | they are exactly solvable, harbor a variety of quantum spin liquid phases, and are also relevant for certain transition metal compounds including the polymorphs of (Na,Li)2IrO3 Iridates and RuCl3. In this review, we give an overview of the rich physics of the Kitaev model, including 2D and 3D fractionalization as well as dynamical correlations and behavior at finite temperatures. We discuss the different materials, and argue how the Kitaev model physics can be relevant even though most materials show magnetic ordering at low temperatures. arXiv:1705.01740v1 [cond-mat.str-el] 4 May 2017 2 CONTENTS I. Introduction 2 II. Kitaev quantum spin liquids 3 A. The Kitaev model 3 B. Classifying Kitaev quantum spin liquids by projective symmetries 4 C. Confinement and finite temperature 5 III. Symmetry and chemistry of the Kitaev exchange 6 IV. -
The Second-Order Correction to the Energy and Momentum in Plane Symmetric Gravitational Waves Like Spacetimes
S S symmetry Article The Second-Order Correction to the Energy and Momentum in Plane Symmetric Gravitational Waves Like Spacetimes Mutahir Ali *, Farhad Ali , Abdus Saboor, M. Saad Ghafar and Amir Sultan Khan Department of Mathematics, Kohat University of Science and Technology, Kohat 26000, Pakistan; [email protected] (F.A.); [email protected] (A.S.); [email protected] (M.S.G.); [email protected] (A.S.K.) * Correspondence: [email protected] Received: 5 December 2018; Accepted: 22 January 2019; Published: 13 February 2019 Abstract: This research provides second-order approximate Noether symmetries of geodetic Lagrangian of time-conformal plane symmetric spacetime. A time-conformal factor is of the form ee f (t) which perturbs the plane symmetric static spacetime, where e is small a positive parameter that produces perturbation in the spacetime. By considering the perturbation up to second-order in e in plane symmetric spacetime, we find the second order approximate Noether symmetries for the corresponding Lagrangian. Using Noether theorem, the corresponding second order approximate conservation laws are investigated for plane symmetric gravitational waves like spacetimes. This technique tells about the energy content of the gravitational waves. Keywords: Einstein field equations; time conformal spacetime; approximate conservation of energy 1. Introduction Gravitational waves are ripples in the fabric of space-time produced by some of the most violent and energetic processes like colliding black holes or closely orbiting black holes and neutron stars (binary pulsars). These waves travel with the speed of light and depend on their sources [1–5]. The study of these waves provide us useful information about their sources (black holes and neutron stars). -
What's Inside
Newsletter A publication of the Controlled Release Society Volume 32 • Number 1 • 2015 What’s Inside 42nd CRS Annual Meeting & Exposition pH-Responsive Fluorescence Polymer Probe for Tumor pH Targeting In Situ-Gelling Hydrogels for Ophthalmic Drug Delivery Using a Microinjection Device Interview with Paolo Colombo Patent Watch Robert Langer Awarded the Queen Elizabeth Prize for Engineering Newsletter Charles Frey Vol. 32 • No. 1 • 2015 Editor Table of Contents From the Editor .................................................................................................................. 2 From the President ............................................................................................................ 3 Interview Steven Giannos An Interview with Paolo Colombo from University of Parma .............................................. 4 Editor 42nd CRS Annual Meeting & Exposition .......................................................................... 6 What’s on Board Access the Future of Delivery Science and Technology with Key CRS Resources .............. 9 Scientifically Speaking pH-Responsive Fluorescence Polymer Probe for Tumor pH Targeting ............................. 10 Arlene McDowell Editor In Situ-Gelling Hydrogels for Ophthalmic Drug Delivery Using a Microinjection Device ........................................................................................................ 12 Patent Watch ................................................................................................................... 14 Special -
Kitaev Materials
Kitaev Materials Simon Trebst Institute for Theoretical Physics University of Cologne, 50937 Cologne, Germany Contents 1 Spin-orbit entangled Mott insulators 2 1.1 Bond-directional interactions . 4 1.2 Kitaev model . 6 2 Honeycomb Kitaev materials 9 2.1 Na2IrO3 ...................................... 9 2.2 ↵-Li2IrO3 ..................................... 10 2.3 ↵-RuCl3 ...................................... 11 3 Triangular Kitaev materials 15 3.1 Ba3IrxTi3 xO9 ................................... 15 − 3.2 Other materials . 17 4 Three-dimensional Kitaev materials 17 4.1 Conceptual overview . 18 4.2 β-Li2IrO3 and γ-Li2IrO3 ............................. 22 4.3 Other materials . 23 5 Outlook 24 arXiv:1701.07056v1 [cond-mat.str-el] 24 Jan 2017 Lecture Notes of the 48th IFF Spring School “Topological Matter – Topological Insulators, Skyrmions and Majoranas” (Forschungszentrum Julich,¨ 2017). All rights reserved. 2 Simon Trebst 1 Spin-orbit entangled Mott insulators Transition-metal oxides with partially filled 4d and 5d shells exhibit an intricate interplay of electronic, spin, and orbital degrees of freedom arising from a largely accidental balance of electronic correlations, spin-orbit entanglement, and crystal-field effects [1]. With different ma- terials exhibiting slight tilts towards one of the three effects, a remarkably broad variety of novel forms of quantum matter can be explored. On the theoretical side, topology is found to play a crucial role in these systems – an observation which, in the weakly correlated regime, has lead to the discovery of the topological band insulator [2, 3] and subsequently its metallic cousin, the Weyl semi-metal [4, 5]. Upon increasing electronic correlations, Mott insulators with unusual local moments such as spin-orbit entangled degrees of freedom can form and whose collective behavior gives rise to unconventional types of magnetism including the formation of quadrupo- lar correlations or the emergence of so-called spin liquid states.