CURRICULUM VITAE June, 2016 Hu, Bei-Lok Bernard Professor Of
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The Future of Fundamental Physics
The Future of Fundamental Physics Nima Arkani-Hamed Abstract: Fundamental physics began the twentieth century with the twin revolutions of relativity and quantum mechanics, and much of the second half of the century was devoted to the con- struction of a theoretical structure unifying these radical ideas. But this foundation has also led us to a number of paradoxes in our understanding of nature. Attempts to make sense of quantum mechanics and gravity at the smallest distance scales lead inexorably to the conclusion that space- Downloaded from http://direct.mit.edu/daed/article-pdf/141/3/53/1830482/daed_a_00161.pdf by guest on 23 September 2021 time is an approximate notion that must emerge from more primitive building blocks. Further- more, violent short-distance quantum fluctuations in the vacuum seem to make the existence of a macroscopic world wildly implausible, and yet we live comfortably in a huge universe. What, if anything, tames these fluctuations? Why is there a macroscopic universe? These are two of the central theoretical challenges of fundamental physics in the twenty-½rst century. In this essay, I describe the circle of ideas surrounding these questions, as well as some of the theoretical and experimental fronts on which they are being attacked. Ever since Newton realized that the same force of gravity pulling down on an apple is also responsible for keeping the moon orbiting the Earth, funda- mental physics has been driven by the program of uni½cation: the realization that seemingly disparate phenomena are in fact different aspects of the same underlying cause. By the mid-1800s, electricity and magnetism were seen as different aspects of elec- tromagnetism, and a seemingly unrelated phenom- enon–light–was understood to be the undulation of electric and magnetic ½elds. -
Quantum Field Theory*
Quantum Field Theory y Frank Wilczek Institute for Advanced Study, School of Natural Science, Olden Lane, Princeton, NJ 08540 I discuss the general principles underlying quantum eld theory, and attempt to identify its most profound consequences. The deep est of these consequences result from the in nite number of degrees of freedom invoked to implement lo cality.Imention a few of its most striking successes, b oth achieved and prosp ective. Possible limitation s of quantum eld theory are viewed in the light of its history. I. SURVEY Quantum eld theory is the framework in which the regnant theories of the electroweak and strong interactions, which together form the Standard Mo del, are formulated. Quantum electro dynamics (QED), b esides providing a com- plete foundation for atomic physics and chemistry, has supp orted calculations of physical quantities with unparalleled precision. The exp erimentally measured value of the magnetic dip ole moment of the muon, 11 (g 2) = 233 184 600 (1680) 10 ; (1) exp: for example, should b e compared with the theoretical prediction 11 (g 2) = 233 183 478 (308) 10 : (2) theor: In quantum chromo dynamics (QCD) we cannot, for the forseeable future, aspire to to comparable accuracy.Yet QCD provides di erent, and at least equally impressive, evidence for the validity of the basic principles of quantum eld theory. Indeed, b ecause in QCD the interactions are stronger, QCD manifests a wider variety of phenomena characteristic of quantum eld theory. These include esp ecially running of the e ective coupling with distance or energy scale and the phenomenon of con nement. -
The Flexibility of Optical Metrics
Home Search Collections Journals About Contact us My IOPscience The flexibility of optical metrics This content has been downloaded from IOPscience. Please scroll down to see the full text. 2016 Class. Quantum Grav. 33 165008 (http://iopscience.iop.org/0264-9381/33/16/165008) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 128.220.159.5 This content was downloaded on 08/05/2017 at 21:52 Please note that terms and conditions apply. You may also be interested in: Induced optical metric in the non-impedance-matched media S A Mousavi, R Roknizadeh and S Sahebdivan Lux in obscuro: photon orbits of extremal black holes revisited Fech Scen Khoo and Yen Chin Ong Hidden geometries in nonlinear theories: a novel aspect of analogue gravity E Goulart, M Novello, F T Falciano et al. Black holes and stars in Horndeski theory Eugeny Babichev, Christos Charmousis and Antoine Lehébel Singularities in GR coupled to nonlinearelectrodynamics M Novello, S E Perez Bergliaffa and J M Salim Parity horizons in shape dynamics Gabriel Herczeg Numerical methods for finding stationary gravitational solutions Óscar J C Dias, Jorge E Santos and Benson Way Static spherically symmetric solutions in mimetic gravity: rotation curves and wormholes Ratbay Myrzakulov, Lorenzo Sebastiani, Sunny Vagnozzi et al. Supersymmetric solutions of N = (2, 0) topologically massive supergravity Nihat Sadik Deger and George Moutsopoulos Classical and Quantum Gravity Class. Quantum Grav. 33 (2016) 165008 (14pp) doi:10.1088/0264-9381/33/16/165008 -
Annual Report to Industry Canada Covering The
Annual Report to Industry Canada Covering the Objectives, Activities and Finances for the period August 1, 2008 to July 31, 2009 and Statement of Objectives for Next Year and the Future Perimeter Institute for Theoretical Physics 31 Caroline Street North Waterloo, Ontario N2L 2Y5 Table of Contents Pages Period A. August 1, 2008 to July 31, 2009 Objectives, Activities and Finances 2-52 Statement of Objectives, Introduction Objectives 1-12 with Related Activities and Achievements Financial Statements, Expenditures, Criteria and Investment Strategy Period B. August 1, 2009 and Beyond Statement of Objectives for Next Year and Future 53-54 1 Statement of Objectives Introduction In 2008-9, the Institute achieved many important objectives of its mandate, which is to advance pure research in specific areas of theoretical physics, and to provide high quality outreach programs that educate and inspire the Canadian public, particularly young people, about the importance of basic research, discovery and innovation. Full details are provided in the body of the report below, but it is worth highlighting several major milestones. These include: In October 2008, Prof. Neil Turok officially became Director of Perimeter Institute. Dr. Turok brings outstanding credentials both as a scientist and as a visionary leader, with the ability and ambition to position PI among the best theoretical physics research institutes in the world. Throughout the last year, Perimeter Institute‘s growing reputation and targeted recruitment activities led to an increased number of scientific visitors, and rapid growth of its research community. Chart 1. Growth of PI scientific staff and associated researchers since inception, 2001-2009. -
Introduction to General Relativity
INTRODUCTION TO GENERAL RELATIVITY Gerard 't Hooft Institute for Theoretical Physics Utrecht University and Spinoza Institute Postbox 80.195 3508 TD Utrecht, the Netherlands e-mail: [email protected] internet: http://www.phys.uu.nl/~thooft/ Version November 2010 1 Prologue General relativity is a beautiful scheme for describing the gravitational ¯eld and the equations it obeys. Nowadays this theory is often used as a prototype for other, more intricate constructions to describe forces between elementary particles or other branches of fundamental physics. This is why in an introduction to general relativity it is of importance to separate as clearly as possible the various ingredients that together give shape to this paradigm. After explaining the physical motivations we ¯rst introduce curved coordinates, then add to this the notion of an a±ne connection ¯eld and only as a later step add to that the metric ¯eld. One then sees clearly how space and time get more and more structure, until ¯nally all we have to do is deduce Einstein's ¯eld equations. These notes materialized when I was asked to present some lectures on General Rela- tivity. Small changes were made over the years. I decided to make them freely available on the web, via my home page. Some readers expressed their irritation over the fact that after 12 pages I switch notation: the i in the time components of vectors disappears, and the metric becomes the ¡ + + + metric. Why this \inconsistency" in the notation? There were two reasons for this. The transition is made where we proceed from special relativity to general relativity. -
"Eternal" Questions in the XX-Century Theoretical Physics V
Philosophical roots of the "eternal" questions in the XX-century theoretical physics V. Ihnatovych Department of Philosophy, National Technical University of Ukraine “Kyiv Polytechnic Institute”, Kyiv, Ukraine e-mail: [email protected] Abstract The evolution of theoretical physics in the XX century differs significantly from that in XVII-XIX centuries. While continuous progress is observed for theoretical physics in XVII-XIX centuries, modern physics contains many questions that have not been resolved despite many decades of discussion. Based upon the analysis of works by the founders of the XX-century physics, the conclusion is made that the roots of the "eternal" questions by the XX-century theoretical physics lie in the philosophy used by its founders. The conclusion is made about the need to use the ideas of philosophy that guided C. Huygens, I. Newton, W. Thomson (Lord Kelvin), J. K. Maxwell, and the other great physicists of the XVII-XIX centuries, in all areas of theoretical physics. 1. Classical Physics The history of theoretical physics begins in 1687 with the work “Mathematical Principles of Natural Philosophy” by Isaac Newton. Even today, this work is an example of what a full and consistent outline of the physical theory should be. It contains everything necessary for such an outline – definition of basic concepts, the complete list of underlying laws, presentation of methods of theoretical research, rigorous proofs. In the eighteenth century, such great physicists and mathematicians as Euler, D'Alembert, Lagrange, Laplace and others developed mechanics, hydrodynamics, acoustics and nebular mechanics on the basis of the ideas of Newton's “Principles”. -
The Universe Unveiled Given by Prof Carlo Contaldi
Friends of Imperial Theoretical Physics We are delighted to announce that the first FITP event of 2015 will be a talk entitled The Universe Unveiled given by Prof Carlo Contaldi. The event is free and open to all but please register by visiting the Eventbrite website via http://tinyurl.com/fitptalk2015. Date: 29th April 2015 Venue: Lecture Theatre 1, Blackett Laboratory, Physics Department, ICL Time: 7-8pm followed by a reception in the level 8 Common room Speaker: Professor Carlo Contaldi The Universe Unveiled The past 25 years have seen our understanding of the Universe we live in being revolutionised by a series of stunning observational campaigns and theoretical advances. We now know the composition, age, geometry and evolutionary history of the Universe to an astonishing degree of precision. A surprising aspect of this journey of discovery is that it has revealed some profound conundrums that challenge the most basic tenets of fundamental physics. We still do not understand the nature of 95% of the matter and energy that seems to fill the Universe, we still do not know why or how the Universe came into being, and we have yet to build a consistent "theory of everything" that can describe the evolution of the Universe during the first few instances after the Big Bang. In this lecture I will review what we know about the Universe today and discuss the exciting experimental and theoretical advances happening in cosmology, including the controversy surrounding last year's BICEP2 "discovery". Biography of the speaker: Professor Contaldi gained his PhD in theoretical physics in 2000 at Imperial College working on theories describing the formation of structures in the universe. -
Quantum Theory Needs No 'Interpretation'
Quantum Theory Needs No ‘Interpretation’ But ‘Theoretical Formal-Conceptual Unity’ (Or: Escaping Adán Cabello’s “Map of Madness” With the Help of David Deutsch’s Explanations) Christian de Ronde∗ Philosophy Institute Dr. A. Korn, Buenos Aires University - CONICET Engineering Institute - National University Arturo Jauretche, Argentina Federal University of Santa Catarina, Brazil. Center Leo Apostel fot Interdisciplinary Studies, Brussels Free University, Belgium Abstract In the year 2000, in a paper titled Quantum Theory Needs No ‘Interpretation’, Chris Fuchs and Asher Peres presented a series of instrumentalist arguments against the role played by ‘interpretations’ in QM. Since then —quite regardless of the publication of this paper— the number of interpretations has experienced a continuous growth constituting what Adán Cabello has characterized as a “map of madness”. In this work, we discuss the reasons behind this dangerous fragmentation in understanding and provide new arguments against the need of interpretations in QM which —opposite to those of Fuchs and Peres— are derived from a representational realist understanding of theories —grounded in the writings of Einstein, Heisenberg and Pauli. Furthermore, we will argue that there are reasons to believe that the creation of ‘interpretations’ for the theory of quanta has functioned as a trap designed by anti-realists in order to imprison realists in a labyrinth with no exit. Taking as a standpoint the critical analysis by David Deutsch to the anti-realist understanding of physics, we attempt to address the references and roles played by ‘theory’ and ‘observation’. In this respect, we will argue that the key to escape the anti-realist trap of interpretation is to recognize that —as Einstein told Heisenberg almost one century ago— it is only the theory which can tell you what can be observed. -
Analogue Stochastic Gravity Phenomena in Two-Component Bose-Einstein Condensates: Sound Cone fluctuations
Analogue stochastic gravity phenomena in two-component Bose-Einstein condensates: Sound cone fluctuations Wei-Can Syu,∗ Da-Shin Lee,y and Chi-Yong Linz Department of Physics, National Dong-Hwa University, Hualien, Taiwan, Republic of China (Dated: July 2, 2019) We investigate the properties of the condensates of cold atoms at zero temperature in the tunable binary Bose-Einstein condensate system with a Rabi transition between atomic hyperfine states. We use this system to examine the effect of quantum fluctuations in a tunable quantum gas on phonon propagation. We show that the system can be represented by a coupled two-field model of a gapless phonon and a gapped mode, which are analogous to the Goldstone and Higgs particles in particle physics. We then further trace out the gapped modes to give an effective purely phononic theory using closed-time-path formalism. In particular, we are interested in the sound cone fluctuations due to the variation of the speed-of-sound acoustic metric, induced by quantum fluctuations of the gapped modes. These fluctuations can be interpreted as inducing a stochastic space-time, and thus are regarded as analogue phenomena of light cone fluctuations presumably arising from quantum gravity effects. The effects of fluctuations can be displayed in the variation in the travel time of sound waves. We suggest the relevant experiments to discuss the possibility of experimental observations. PACS numbers: 04.62.+v, 03.75.Kk,03.65.Yz I. INTRODUCTION less, these stochastic spacetimes can arise also from the quantum nature of the gravitational field, namely gravi- tons. One particularly striking effect of spacetime geom- Analog models of gravity are the attempts to use lab- etry fluctuations is that a fixed light cone does not exist, oratory systems for modeling various phenomena of gen- giving rise to light cone fluctuations with their tiny effects eral relativity (e.g., black holes or cosmological geome- on the blurring of the images of astronomical objects, or tries), which require a deeper understanding of (stochas- luminosity fluctuations [4{7]. -
Report of MARIO NOVELLO (2012)
Report of MARIO NOVELLO (2012) List of papers and some comments on the lines of research I have been developing and the ones I shall be developing in the coming years. 1. Gordon Metric Revisited, M. Novello and E. Bittencourt, to be published in Phys.Rev. D. We show that Gordon metric belongs to a larger class of geometries, which are responsible to describe the paths of accelerated bodies in moving dielectrics as geodesics in a metric $\hat q_{\mu\nu}$ different from the background one. This map depends only on the background metric and on the motion of the bodies under consideration. As a consequence, this method describes a more general property that concerns the elimination of any kind of force acting on bodies by a suitable change of the substratum metric. 2. What is the origin of the mass of the Higgs boson? M. Novello and E. Bittencourt, Phys.Rev. D86 (2012) 063510. The purpose of this paper is to present a unified description of mass generation mechanisms that have been investigated so far and that are called the Mach and Higgs proposals. In our mechanism, gravity acts merely as a catalyst and the final expression of the mass depends neither on the intensity nor on the particular properties of the gravitational field. We shall see that these two strategies to provide mass for all bodies that operate independently and competitively can be combined into a single unified theoretical framework. As a consequence of this new formulation we are able to present an answer to the question: what is the origin of the mass of the Higgs boson? This paper is a continuation of the program of the analysis of the mechanisms of mass generation that was started in 2011 with the work presented in CQG entitled: 3. -
Annual Report for the Fiscal Year July 1, 1980
The Institute for Advanced Study .nnual Report 1980 This Annual Report has been made possible by a generous grant from the Union Carbide Corporation. ! The Institute for Advanced Study Annual Report for the Fiscal Year July 1, 1980-June 30, 1981 The Institute for Advanced Study Olden Lane Princeton, New Jersey 08540 U.S.A. Printed by Princeton University Press Designed by Bruce Campbell x4S36 /98I It is fundamental to our purpose, and our Extract from the letter addressed by the express desire, that in the appointments to Founders to the Institute's Trustees, the staff and faculty, as well as in the dated June 6, 1930, Newark, New Jersey. admission of workers and students, no account shall be taken, directly or indirectly, of race, religion or sex. We feel strongly that the spirit characteristic of America at its noblest, above all, the pursuit of higher learning, cannot admit of any conditions as to personnel other than those designed to promote the objects for which this institution is established, and particularly with no regard whatever to accidents of race, creed or sex. /r2- S39 Table of Contents Trustees and Officers Founders Caroline Bamberger Fuld Louis Bamberger Board of Trustees Daniel Bell Howard C. Kauffmann Professor of Sociology President Harvard University Exxon Corporation Charles L. Brown John R. Opel Chairman the Board of and Chief President and Chief Executive Officer Executive Officer IBM Corporation American Telephone and Telegraph Company Howard C. Petersen Philadelphia, Pennsylvania Fletcher L. Byrom Chairman of the Board Martin E. Segal Koppers Company, Inc. Partner, Wertheim & Co.; Chairman, Martin E. -
Reflection Coefficient for Superresonant Scattering
Reflection coefficient for superresonant scattering Soumen Basak∗ and Parthasarathi Majumdar† The Institute Of Mathematical sciences Chennai-6000113, INDIA We investigate superresonant scattering of acoustic disturbances from a rotating acoustic black hole in the low frequency range. We derive an expression for the reflection coefficient, exhibiting its frequency dependence in this regime. I. INTRODUCTION Progress in understanding black hole radiance, both in the semiclassical and quantum gravitational regimes, have suffered greatly in the past, due to the lack of experimental feedback. Black hole radiance consists of spontaneous radiation (Hawking radiation) [1]as well as stimulated emission (superradiance) [2], [3], [4], [5]. For astrophysical black holes, the Hawking temperature is invariably smaller than the Cosmic Microwave Background temperature. So the black hole mostly accretes rather than radiates spontaneously. Similarly, superradiant emission is also hard to observe from within a background of x-rays being emitted from accretion processes. Due to these reasons physicists have been looking for alternative physical models of gravity so that experiments can be devised for indirect verification of phenomena that are predicted by the semiclassical theory of gravity. These alternative physical models are called analog models of gravity. Among the first of such analog gravity models, Unruh’s [6] was the pioneering idea of analog models based on fluid mechanics. The idea of such models arose from a remarkable observation regarding sound wave propagation in a fluid in motion. Unruh showed that if the fluid is barotropic and inviscid, and the flow is irrotational, the equation of motion of the acoustic fluctuations of the velocity potential is identical to that of a minimally coupled massless scalar field in an effective (3+1) dimensional curved spacetime, and is given by, 1 µν ✷Ψ= ∂µ √ g g ∂ν Ψ=0 (1) √ g − − where gµν is the ‘acoustic’ metric and Ψ is the fluctuation of the velocity potential.