Scrambling and Decoding the Charged Quantum Information
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Toy Models for Black Hole Evaporation
UCSBTH-92-36 hep-th/9209113 Toy Models for Black Hole Evaporation∗ Steven B. Giddings† Department of Physics University of California Santa Barbara, CA 93106-9530 Abstract These notes first present a brief summary of the puzzle of information loss to black holes, of its proposed resolutions, and of the flaws in the proposed resolutions. There follows a review of recent attempts to attack this problem, and other issues in black hole physics, using two-dimensional dilaton gravity theories as toy models. These toy models contain collapsing black holes and have for the first time enabled an explicit semiclassical treatment of the backreaction of the Hawking radiation on the geometry of an evaporating black hole. However, a complete answer to the information conundrum seems to require physics beyond the semiclassical approximation. Preliminary attempts to make progress arXiv:hep-th/9209113v2 11 Nov 1992 in this direction, using connections to conformal field theory, are described. *To appear in the proceedings of the International Workshop of Theoretical Physics, 6th Session, String Quantum Gravity and Physics at the Planck Energy Scale, 21 – 28 June 1992, Erice, Italy. † Email addresses: [email protected], [email protected]. Since the discovery of black holes, physicists have been faced with the possibility that they engender a breakdown of predictability. At the classical level this breakdown arises at the singularity. Classically we do not know how to evolve past it. Inclusion of quantum effects may serve as a remedy, allowing predictable evolution, by smoothing out the singularities of general relativity. However, as suggested by Hawking [1,2], quantum effects also present another sharp challenge to predictability through the mechanism of Hawking evaporation. -
Quantum Vacuum Energy Density and Unifying Perspectives Between Gravity and Quantum Behaviour of Matter
Annales de la Fondation Louis de Broglie, Volume 42, numéro 2, 2017 251 Quantum vacuum energy density and unifying perspectives between gravity and quantum behaviour of matter Davide Fiscalettia, Amrit Sorlib aSpaceLife Institute, S. Lorenzo in Campo (PU), Italy corresponding author, email: [email protected] bSpaceLife Institute, S. Lorenzo in Campo (PU), Italy Foundations of Physics Institute, Idrija, Slovenia email: [email protected] ABSTRACT. A model of a three-dimensional quantum vacuum based on Planck energy density as a universal property of a granular space is suggested. This model introduces the possibility to interpret gravity and the quantum behaviour of matter as two different aspects of the same origin. The change of the quantum vacuum energy density can be considered as the fundamental medium which determines a bridge between gravity and the quantum behaviour, leading to new interest- ing perspectives about the problem of unifying gravity with quantum theory. PACS numbers: 04. ; 04.20-q ; 04.50.Kd ; 04.60.-m. Key words: general relativity, three-dimensional space, quantum vac- uum energy density, quantum mechanics, generalized Klein-Gordon equation for the quantum vacuum energy density, generalized Dirac equation for the quantum vacuum energy density. 1 Introduction The standard interpretation of phenomena in gravitational fields is in terms of a fundamentally curved space-time. However, this approach leads to well known problems if one aims to find a unifying picture which takes into account some basic aspects of the quantum theory. For this reason, several authors advocated different ways in order to treat gravitational interaction, in which the space-time manifold can be considered as an emergence of the deepest processes situated at the fundamental level of quantum gravity. -
Atom-Light Interaction and Basic Applications
ICTP-SAIFR school 16.-27. of September 2019 on the Interaction of Light with Cold Atoms Lecture on Atom-Light Interaction and Basic Applications Ph.W. Courteille Universidade de S~aoPaulo Instituto de F´ısicade S~aoCarlos 07/01/2021 2 . 3 . 4 Preface The following notes have been prepared for the ICTP-SAIFR school on 'Interaction of Light with Cold Atoms' held 2019 in S~aoPaulo. They are conceived to support an introductory course on 'Atom-Light Interaction and Basic Applications'. The course is divided into 5 lectures. Cold atomic clouds represent an ideal platform for studies of basic phenomena of light-matter interaction. The invention of powerful cooling and trapping techniques for atoms led to an unprecedented experimental control over all relevant degrees of freedom to a point where the interaction is dominated by weak quantum effects. This course reviews the foundations of this area of physics, emphasizing the role of light forces on the atomic motion. Collective and self-organization phenomena arising from a cooperative reaction of many atoms to incident light will be discussed. The course is meant for graduate students and requires basic knowledge of quan- tum mechanics and electromagnetism at the undergraduate level. The lectures will be complemented by exercises proposed at the end of each lecture. The present notes are mostly extracted from some textbooks (see below) and more in-depth scripts which can be consulted for further reading on the website http://www.ifsc.usp.br/∼strontium/ under the menu item 'Teaching' −! 'Cursos 2019-2' −! 'ICTP-SAIFR pre-doctoral school'. The following literature is recommended for preparation and further reading: Ph.W. -
Spacetime Geometry from Graviton Condensation: a New Perspective on Black Holes
Spacetime Geometry from Graviton Condensation: A new Perspective on Black Holes Sophia Zielinski née Müller München 2015 Spacetime Geometry from Graviton Condensation: A new Perspective on Black Holes Sophia Zielinski née Müller Dissertation an der Fakultät für Physik der Ludwig–Maximilians–Universität München vorgelegt von Sophia Zielinski geb. Müller aus Stuttgart München, den 18. Dezember 2015 Erstgutachter: Prof. Dr. Stefan Hofmann Zweitgutachter: Prof. Dr. Georgi Dvali Tag der mündlichen Prüfung: 13. April 2016 Contents Zusammenfassung ix Abstract xi Introduction 1 Naturalness problems . .1 The hierarchy problem . .1 The strong CP problem . .2 The cosmological constant problem . .3 Problems of gravity ... .3 ... in the UV . .4 ... in the IR and in general . .5 Outline . .7 I The classical description of spacetime geometry 9 1 The problem of singularities 11 1.1 Singularities in GR vs. other gauge theories . 11 1.2 Defining spacetime singularities . 12 1.3 On the singularity theorems . 13 1.3.1 Energy conditions and the Raychaudhuri equation . 13 1.3.2 Causality conditions . 15 1.3.3 Initial and boundary conditions . 16 1.3.4 Outlining the proof of the Hawking-Penrose theorem . 16 1.3.5 Discussion on the Hawking-Penrose theorem . 17 1.4 Limitations of singularity forecasts . 17 2 Towards a quantum theoretical probing of classical black holes 19 2.1 Defining quantum mechanical singularities . 19 2.1.1 Checking for quantum mechanical singularities in an example spacetime . 21 2.2 Extending the singularity analysis to quantum field theory . 22 2.2.1 Schrödinger representation of quantum field theory . 23 2.2.2 Quantum field probes of black hole singularities . -
Taxonomy of Belarusian Educational and Research Portal of Nuclear Knowledge
Taxonomy of Belarusian Educational and Research Portal of Nuclear Knowledge S. Sytova� A. Lobko, S. Charapitsa Research Institute for Nuclear Problems, Belarusian State University Abstract The necessity and ways to create Belarusian educational and research portal of nuclear knowledge are demonstrated. Draft tax onomy of portal is presented. 1 Introduction President Dwight D. Eisenhower in December 1953 presented to the UN initiative "Atoms for Peace" on the peaceful use of nuclear technology. Today, many countries have a strong nuclear program, while other ones are in the process of its creation. Nowadays there are about 440 nuclear power plants operating in 30 countries around the world. Nuclear reac tors are used as propulsion systems for more than 400 ships. About 300 research reactors operate in 50 countries. Such reactors allow production of radioisotopes for medical diagnostics and therapy of cancer, neutron sources for research and training. Approximately 55 nuclear power plants are under construction and 110 ones are planned. Belarus now joins the club of countries that have or are building nu clear power plant. Our country has a large scientific potential in the field of atomic and nuclear physics. Hence it is obvious the necessity of cre ation of portal of nuclear knowledge. The purpose of its creation is the accumulation and development of knowledge in the nuclear field as well as popularization of nuclear knowledge for the general public. *E-mail:[email protected] 212 Wisdom, enlightenment Figure 1: Knowledge management 2 Nuclear knowledge Since beginning of the XXI century the International Atomic Energy Agen cy (IAEA) gives big attention to the nuclear knowledge management (NKM) [1]-[3] . -
Canadian-Built Laser Chills Antimatter to Near Absolute Zero for First Time Researchers Achieve World’S First Manipulation of Antimatter by Laser
UNDER EMBARGO UNTIL 8:00 AM PT ON WED MARCH 31, 2021 DO NOT DISTRIBUTE BEFORE EMBARGO LIFT Canadian-built laser chills antimatter to near absolute zero for first time Researchers achieve world’s first manipulation of antimatter by laser Vancouver, BC – Researchers with the CERN-based ALPHA collaboration have announced the world’s first laser-based manipulation of antimatter, leveraging a made-in-Canada laser system to cool a sample of antimatter down to near absolute zero. The achievement, detailed in an article published today and featured on the cover of the journal Nature, will significantly alter the landscape of antimatter research and advance the next generation of experiments. Antimatter is the otherworldly counterpart to matter; it exhibits near-identical characteristics and behaviours but has opposite charge. Because they annihilate upon contact with matter, antimatter atoms are exceptionally difficult to create and control in our world and had never before been manipulated with a laser. “Today’s results are the culmination of a years-long program of research and engineering, conducted at UBC but supported by partners from across the country,” said Takamasa Momose, the University of British Columbia (UBC) researcher with ALPHA’s Canadian team (ALPHA-Canada) who led the development of the laser. “With this technique, we can address long-standing mysteries like: ‘How does antimatter respond to gravity? Can antimatter help us understand symmetries in physics?’. These answers may fundamentally alter our understanding of our Universe.” Since its introduction 40 years ago, laser manipulation and cooling of ordinary atoms have revolutionized modern atomic physics and enabled several Nobel-winning experiments. -
Evidence for a Sublattice Weak Gravity Conjecture
Evidence for a Sublattice Weak Gravity Conjecture The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Heidenreich, Ben, Matthew Reece, and Tom Rudelius. 2017. Evidence for a Sublattice Weak Gravity Conjecture. Journal of High Energy Physics 2017, 25. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:41392811 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#OAP Prepared for submission to JHEP Evidence for a Sublattice Weak Gravity Conjecture Ben Heidenreich,a;b Matthew Reece,a and Tom Rudeliusa aDepartment of Physics, Harvard University, Cambridge, MA 02138, USA bPerimeter Institute for Theoretical Physics, Waterloo, Ontario, Canada N2L 2Y5 E-mail: [email protected], [email protected], [email protected] Abstract: The Weak Gravity Conjecture postulates the existence of superextremal charged particles, i.e. those with mass smaller than or equal to their charge in Planck units. We present further evidence for our recent observation that in known examples a much stronger statement is true: an infinite tower of superextremal particles of different charges exists. We show that effective Kaluza-Klein field theories and perturbative string vacua respect the Sublattice Weak Gravity Conjecture, namely that a finite index sublattice of the full charge lattice exists with a superextremal particle at each site. In perturbative string theory we show that this follows from modular invariance. -
Black Holes and Gravitational Waves in Models of Minicharged Dark Matter
Home Search Collections Journals About Contact us My IOPscience Black holes and gravitational waves in models of minicharged dark matter This content has been downloaded from IOPscience. Please scroll down to see the full text. JCAP05(2016)054 (http://iopscience.iop.org/1475-7516/2016/05/054) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 62.210.105.116 This content was downloaded on 28/06/2016 at 17:13 Please note that terms and conditions apply. ournal of Cosmology and Astroparticle Physics JAn IOP and SISSA journal Black holes and gravitational waves in models of minicharged dark matter JCAP05(2016)054 Vitor Cardoso,a;b Caio F.B. Macedo,a Paolo Pania;c and Valeria Ferraric aCENTRA, Departamento de F´ısica,Instituto Superior T´ecnico| IST, Universidade de Lisboa | UL, Avenida Rovisco Pais 1, 1049 Lisboa, Portugal bPerimeter Institute for Theoretical Physics, 31 Caroline Street North Waterloo, Ontario N2L 2Y5, Canada cDipartimento di Fisica, \Sapienza" Universit`adi Roma and Sezione INFN Roma1, Piazzale A. Moro 5, 00185, Roma, Italy E-mail: [email protected], [email protected], [email protected], [email protected] Received April 29, 2016 Revised May 16, 2016 Accepted May 17, 2016 Published May 23, 2016 Abstract. In viable models of minicharged dark matter, astrophysical black holes might be charged under a hidden U(1) symmetry and are formally described by the same Kerr- Newman solution of Einstein-Maxwell theory. These objects are unique probes of minicharged dark matter and dark photons. -
Atomic Physicsphysics AAA Powerpointpowerpointpowerpoint Presentationpresentationpresentation Bybyby Paulpaulpaul E.E.E
ChapterChapter 38C38C -- AtomicAtomic PhysicsPhysics AAA PowerPointPowerPointPowerPoint PresentationPresentationPresentation bybyby PaulPaulPaul E.E.E. Tippens,Tippens,Tippens, ProfessorProfessorProfessor ofofof PhysicsPhysicsPhysics SouthernSouthernSouthern PolytechnicPolytechnicPolytechnic StateStateState UniversityUniversityUniversity © 2007 Objectives:Objectives: AfterAfter completingcompleting thisthis module,module, youyou shouldshould bebe ableable to:to: •• DiscussDiscuss thethe earlyearly modelsmodels ofof thethe atomatom leadingleading toto thethe BohrBohr theorytheory ofof thethe atom.atom. •• DemonstrateDemonstrate youryour understandingunderstanding ofof emissionemission andand absorptionabsorption spectraspectra andand predictpredict thethe wavelengthswavelengths oror frequenciesfrequencies ofof thethe BalmerBalmer,, LymanLyman,, andand PashenPashen spectralspectral series.series. •• CalculateCalculate thethe energyenergy emittedemitted oror absorbedabsorbed byby thethe hydrogenhydrogen atomatom whenwhen thethe electronelectron movesmoves toto aa higherhigher oror lowerlower energyenergy level.level. PropertiesProperties ofof AtomsAtoms ••• AtomsAtomsAtoms areareare stablestablestable andandand electricallyelectricallyelectrically neutral.neutral.neutral. ••• AtomsAtomsAtoms havehavehave chemicalchemicalchemical propertiespropertiesproperties whichwhichwhich allowallowallow themthemthem tototo combinecombinecombine withwithwith otherotherother atoms.atoms.atoms. ••• AtomsAtomsAtoms emitemitemit andandand absorbabsorbabsorb -
Manipulating Atoms with Photons
Manipulating Atoms with Photons Claude Cohen-Tannoudji and Jean Dalibard, Laboratoire Kastler Brossel¤ and Coll`ege de France, 24 rue Lhomond, 75005 Paris, France ¤Unit¶e de Recherche de l'Ecole normale sup¶erieure et de l'Universit¶e Pierre et Marie Curie, associ¶ee au CNRS. 1 Contents 1 Introduction 4 2 Manipulation of the internal state of an atom 5 2.1 Angular momentum of atoms and photons. 5 Polarization selection rules. 6 2.2 Optical pumping . 6 Magnetic resonance imaging with optical pumping. 7 2.3 Light broadening and light shifts . 8 3 Electromagnetic forces and trapping 9 3.1 Trapping of charged particles . 10 The Paul trap. 10 The Penning trap. 10 Applications. 11 3.2 Magnetic dipole force . 11 Magnetic trapping of neutral atoms. 12 3.3 Electric dipole force . 12 Permanent dipole moment: molecules. 12 Induced dipole moment: atoms. 13 Resonant dipole force. 14 Dipole traps for neutral atoms. 15 Optical lattices. 15 Atom mirrors. 15 3.4 The radiation pressure force . 16 Recoil of an atom emitting or absorbing a photon. 16 The radiation pressure in a resonant light wave. 17 Stopping an atomic beam. 17 The magneto-optical trap. 18 4 Cooling of atoms 19 4.1 Doppler cooling . 19 Limit of Doppler cooling. 20 4.2 Sisyphus cooling . 20 Limits of Sisyphus cooling. 22 4.3 Sub-recoil cooling . 22 Subrecoil cooling of free particles. 23 Sideband cooling of trapped ions. 23 Velocity scales for laser cooling. 25 2 5 Applications of ultra-cold atoms 26 5.1 Atom clocks . 26 5.2 Atom optics and interferometry . -
22. Atomic Physics and Quantum Mechanics
22. Atomic Physics and Quantum Mechanics S. Teitel April 14, 2009 Most of what you have been learning this semester and last has been 19th century physics. Indeed, Maxwell's theory of electromagnetism, combined with Newton's laws of mechanics, seemed at that time to express virtually a complete \solution" to all known physical problems. However, already by the 1890's physicists were grappling with certain experimental observations that did not seem to fit these existing theories. To explain these puzzling phenomena, the early part of the 20th century witnessed revolutionary new ideas that changed forever our notions about the physical nature of matter and the theories needed to explain how matter behaves. In this lecture we hope to give the briefest introduction to some of these ideas. 1 Photons You have already heard in lecture 20 about the photoelectric effect, in which light shining on the surface of a metal results in the emission of electrons from that surface. To explain the observed energies of these emitted elec- trons, Einstein proposed in 1905 that the light (which Maxwell beautifully explained as an electromagnetic wave) should be viewed as made up of dis- crete particles. These particles were called photons. The energy of a photon corresponding to a light wave of frequency f is given by, E = hf ; where h = 6:626×10−34 J · s is a new fundamental constant of nature known as Planck's constant. The total energy of a light wave, consisting of some particular number n of photons, should therefore be quantized in integer multiples of the energy of the individual photon, Etotal = nhf. -
A Brief Introduction to the Weak Gravity Conjecture Eran Palti Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
Letters in High Energy Physics LHEP-176, 2020 A Brief Introduction to the Weak Gravity Conjecture Eran Palti Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel Abstract The Weak Gravity Conjecture proposes that a theory with a gauge field that is coupled to gravity must have charged matter on which gravity acts as the weakest force. It also proposes that there is an intrinsic cutoff on such an effective theory, which corresponds to a tower of charged states, that is set by the strength of the gauge coupling (in Planck units). This article is a brief introduction to the Weak Gravity Conjecture, covering aspects of the motivations for it as well as various extensions and refinements. Keywords: Swampland, Quantum Gravity, String Theory gauge fields for simplicity), with gauge coupling g, there must DOI: 10.31526/LHEP.2020.176 exist at least one particle with quantized charge q and mass m which satisfies the bound p 1. INTRODUCTION m ≤ 2gqMp . (4) There are four known forces in the universe: the strong and The bound (4) is termed the Electric WGC. This is to dif- weak forces, electromagnetism, and gravity. The known fun- ferentiate it from a related bound termed the Magnetic WGC. damental matter particles are all charged under at least two The simplest way to introduce this second bound is through the of these forces. For example, the right-handed electron carries electromagnetic dual of (4) [1]. Under electromagnetic duality electromagnetic charge and gravitational charge. These charges the gauge coupling g is exchanged for its inverse g−1, while the can be deduced from the Coulomb forces that two electrons feel electrically charged particle is exchanged for a monopole with when placed a distance r apart.