Theoretical Issues in Numerical Relativity Simulations Daniela Alic
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18Th International Conference on General
18TH INTERNATIONAL CONFERENCE ON GENERAL RELATIVITY AND GRAVITATION (GRG18) 8 – 13 July 2007 7TH EDOARDO AMALDI CONFERENCE ON GRAVITATIONAL WAVES (AMALDI7) www.grg18.com 8 – 14 July 2007 www.Amaldi7.com Sydney Convention & Exhibition Centre • Darling Harbour • Sydney Australia INSPIRALLING BLACK HOLES RAPID EPANSION OF AN UNSTABLE NEUTRON STAR Credit: Seidel (LSU/AEI) / Kaehler (ZIB) Credit: Rezzolla (AEI) / Benger (ZIB) GRAZING COLLISION OF TWO BLACK HOLES VISUALISATION OF A GRAVITATIONAL WAVE HAVING Credit: Seidel (AEI) / Benger (ZIB) TEUKOLSKY'S SOLUTION AS INITIAL DATA Credit: Seidel (AEI) / Benger (ZIB) ROLLER COASTER DISTORTED BY SPECIAL RELATIVISTIC EFFECTS Credit: Michael Hush, Department of Physics, The Australian National University The program for GRG18 will incorporate all areas of General Relativity and Gravitation including Classical General Relativity; Numerical Relativity; Relativistic Astrophysics and Cosmology; Experimental Work on Gravity and Quantum Issues in Gravitation. The program for Amaldi7 will cover all aspects of Gravitational Wave Physics and Detection. PLENARY LECTURES Peter Schneider (Bonn) Donald Marolf USA Bernard Schutz Germany Bernd Bruegman (Friedrich-Schiller-University Jena) Gravitational lensing David McClelland Australia Robin Stebbins United States Numerical relativity Daniel Shaddock (JPL California Institute of Technology) Jorge Pullin USA Kimio Tsubono Japan Daniel Eisenstein (University of Arizona) Gravitational wave detection from space: technology challenges Norna Robertson USA Stefano Vitale Italy Dark energy Stan Whitcomb (California Institute of Technology) Misao Sasaki Japan Clifford Will United States Ground-based gravitational wave detection: now and future Bernard F Schutz Germany Francis Everitt (Stanford University) Susan M. Scott Australia LOCAL ORGANISING COMMITTEE Gravity Probe B and precision tests of General Relativity Chair: Susan M. -
William A. Hiscock Michio Kaku Gordon Kane J-M Wersinger
WILLIAM A. HISCOCK From Wormholes to the Warp Drive: Using Theoretical Physics to Place Ultimate Bounds on Technology MICHIO KAKU M-Theory: Mother of All Superstrings GORDON KANE Anthropic Questions Peering into the Universe: Images from the Hubble Space Telescope J-M WERSINGER The National Space Grant Student Satellite Program: Crawl, Walk, Run, Fly! The Honor Society of Phi Kappa Phi was founded in 1897 and became a national organization Board of Directors through the efforts of the presidents of three state Wendell H. McKenzie, PhD universities. Its primary objective has been from National President the first the recognition and encouragement of Dept. of Genetics superior scholarship in all fields of study. Good Box 7614 NCSU character is an essential supporting attribute for Raleigh, NC 27695 those elected to membership. The motto of the Paul J. Ferlazzo, PhD Society is philosophia krateit¯oph¯ot¯on, which is National President-Elect freely translated as “Let the love of learning rule Northern Arizona University Phi Kappa Phi Forum Staff humanity.” Dept. of English, Bx 6032 Flagstaff, AZ 86011 Editor: JAMES P. KAETZ Donna Clark Schubert National Vice President Associate Editors: Troy State University Phi Kappa Phi encourages and recognizes aca- 101 C Wallace Hall STEPHANIE J. BOND demic excellence through several national pro- Troy, AL 36082 LAURA J. KLOBERG grams. Its flagship National Fellowship Program now awards more than $460,000 each year to Neil R. Luebke, PhD Copy Editor: student members for the first year of graduate Past President 616 W. Harned Ave. AMES ARRS study. In addition, the Society funds Study J T. -
Numerical Relativity: Instituto De Ciencias Instituto De Ciencias UNAMUNAM Nuclearesnucleares on Overview of the Field and Recent Results on Black Hole Simulations
Numerical Relativity: Instituto de Ciencias Instituto de Ciencias UNAMUNAM NuclearesNucleares On overview of the field and recent results on black hole simulations Miguel Alcubierre Instituto de Ciencias Nucleares UNAM, Mexico SIAM Conference, Philadelphia, August 2010 Gravitational wave detectors InstitutoInstitutode de Ciencias Ciencias UNAM Nucleares UNAM NuclearesA global network of gravitational wave detectors in now either in an advanced state of construction, or actually taking data! The collision of compact objects (black holes, neutron stars) is considered one of the most promising sources for detection in the next few years. TAMA, Tokio VIRGO, Pisa LIGO,Washington GEO 600, Hanover LIGO, Louisiana The future: LISA (Laser Interferometer Space Antenna) Instituto de Ciencias Instituto de Ciencias UNAMUNAM NuclearesNucleares Einstein’s field equations Instituto de Ciencias Instituto de Ciencias UNAMUNAM NuclearesNucleares The dynamics of the gravitational field are described by the Einstein field equations: G 8 3,2,1,0 These equations relate the geometry of space‐time (the left hand side) with the distribution of mass and energy (the right hand side). Einstein’s equations form a system of 10 non‐linear, coupled, partial differential equations in 4 dimensions. Written on a general coordinate system they can have thousands of terms! Numerical relativity Instituto de Ciencias Instituto de Ciencias UNAMUNAM NuclearesNucleares There are books full of exact solutions to Einstein’s equations, but few of those solutions have a clear astrophysical interpretation. Exact solutions are typically found by asking for space‐time to have a high degree of symmetry: • Schwarzschild black hole: Static and spherically symmetric. • Kerr black hole: Stationary and axially symmetric. -
There Is Found Actual Science After the Opinions of Force Areas and Invisibility Cloaks
Things that were once just fantastic fiction of science fiction make up many of today's technologies. Did you know that Jules Verne, who was a nineteenth-century science fiction writer, has already dreamed about devices such as fax machines, a worldwide network, and moon rocket ships? Although we accepted these technologies today, Verne's contemporaries, even the leading physicists, laughed them, convinced them to be impossible. Even when you watch sci-fi movies that aren't that old, you can see that some of the technologies depicted today are considered rough, like large computers with lots of flashing bulbs. In some respects, the science of now has exceeded fiction yesterday, although it has not yet passed through other galaxies wearing catsuits. And are you wondering about what will technologies that seem impossible today be? Which of these is going to be achieved in the future and how? You are going to discover if you keep reading. Chapter 1 - There is found actual science after the opinions of force areas and invisibility cloaks. Do you recognize the force fields applied in Star Trek? Challenging energy barriers that preserve starships from rockets and enemy fire? Imaginary, isn't it? The one, that is known in classical physics, is force fields. As it understands, many objects can have an impact on other objects around them without direct contact with them. For example, a magnet pulls or pushes things in an exact field around it. In the nineteenth century, by Michael Faraday who was an English scientist named, it is told that uncovered the concept of force fields, invisible fields, or lines of force surrounding a magnet. -
The Alcubierre Warp Drive Using Lorentz Boosts According to the Harold White Spacetime Metric Potential Θ
The Alcubierre Warp Drive using Lorentz Boosts according to the Harold White Spacetime Metric potential θ. Fernando Loup, Rocha Daniel To cite this version: Fernando Loup, Rocha Daniel. The Alcubierre Warp Drive using Lorentz Boosts according to the Harold White Spacetime Metric potential θ.. 2012. hal-00768779 HAL Id: hal-00768779 https://hal.archives-ouvertes.fr/hal-00768779 Submitted on 23 Dec 2012 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. The Alcubierre Warp Drive using Lorentz Boosts according to the Harold White Spacetime Metric potential θ. Fernando Loup ∗ Daniel Rocha † December 23, 2012 Abstract Warp Drives are solutions of the Einstein Field Equations that allows superluminal travel within the framework of General Relativity. The first of these solutions was discovered by the Mexican math- ematician Miguel Alcubierre in 1994.The Alcubierre warp drive seems to be very attractive because allows interstellar space travel at arbitrarily large speeds avoiding the time dilatation and mass increase paradoxes of Special Relativity. However it suffers from a very serious drawback:Interstellar space is not empty:It is fulfilled with photons and particle dusts and a ship at superluminal speeds would impact these obstacles in highly energetic collisions disrupting the warp field and placing the astronauts in danger.This was pointed out by a great number of authors like Clark,Hiscock,Larson,McMonigal,Lewis,O’Byrne, Barcelo,Finazzi and Liberati. -
The Universe in Another Nutshell
Title – THE UNIVERSE IN ANOTHER NUTSHELL Author – Rodney Bartlett Abstract – This article deals with philosophy, but also provides scientific background in the form of physics and cosmology. Intriguing concepts are the roles of band-gap structures, Einstein's Unified Field and Retrocausality (backward causation)in producing the SUPERHUMANS of the far future. These beings will achieve immortality via quantum entanglement with all space and all time. These superhumans would not exist without you, me and all the mortals who ever lived. However, their entanglement with all space-time means you and I are not separate from them. Is a person's mortal life therefore merely the briefest of passing moments in the grand scheme of things? Do we join those we might call gods when we leave this time and little planet? There are already two universes in a nutshell that I know of. The first, and best known, is “The Universe in a Nutshell” – a 224-page book written by the world- famous English physicist, cosmologist and mathematician Professor Stephen Hawking (born January 8, 1942) that was published by Bantam Spectra on November 6, 2001. The second is “Michio Kaku: The Universe in a Nutshell” – a 42-minute video for The Floating University that is presented by Michio Kaku (born January 24, 1947), Henry Semat Professor of Theoretical Physics at the USA’s CUNY (City University New York). It has been viewed more than 2.6 million times, was uploaded to You Tube on August 15, 2012 and was directed / produced by Jonathan Fowler, Kathleen Russell, and Elizabeth Rodd. -
Arxiv:2103.05610V1
Warp drive basics Miguel Alcubierre ID ∗ Instituto de Ciencias Nucleares, Universidad Nacional Aut´onoma de M´exico, Circuito Exterior C.U., A.P. 70-543, M´exico D.F. 04510, M´exico Francisco S. N. Lobo ID † Instituto de Astrof´ısica e Ciˆencias do Espa¸co, Faculdade de Ciˆencias da Universidade de Lisboa, Edif´ıcio C8, Campo Grande, P-1749-016, Lisbon, Portugal A (Dated: LTEX-ed March 11, 2021) “Warp drive” spacetimes and wormhole geometries are useful as “gedanken-experiments” that force us to confront the foundations of general relativity, and among other issues, to precisely formulate the notion of “superluminal” travel and communication. Here we will consider the basic definition and properties of warp drive spacetimes. In particular, we will discuss the violation of the energy conditions associated with these spacetimes, as well as some other interesting properties such as the appearance of horizons for the superluminal case, and the possibility of using a warp drive to create closed timelike curves. Furthermore, due to the horizon problem, an observer in a spaceship cannot create nor control on demand a warp bubble. To contour this difficulty, we discuss a metric introduced by Krasnikov, which also possesses the interesting property in that the time for a round trip, as measured by clocks at the starting point, can be made arbitrarily short. arXiv:2103.05610v1 [gr-qc] 9 Mar 2021 ∗ [email protected] † [email protected] 2 CONTENTS I. Introduction 2 II. Warp drive spacetime 3 A. Alcubierre warp drive 4 B. Superluminal travel in the warp drive 5 C. -
FASTER-THAN-LIGHT TRAVEL: Are We There Yet? There’S a Cosmic Speed Limit That Unfortunately Means We Won’T Be Firing up Warp Drive Anytime Soon
FASTER-THAN-LIGHT TRAVEL: Are we there yet? There’s a cosmic speed limit that unfortunately means we won’t be firing up warp drive anytime soon. Long before the Empire struck back, before the United Federation of Planets federated, Isaac Asimov created Foundation, the epic tale of the decline and fall of the Galactic Empire. Asimov’s Empire comprised 25 million planets, knit together by sleek spaceships hurtling through the galaxy. And how did these spaceships cross the vast gulf between the stars? By jumping through hyperspace, of course, as Asimov himself explains in Foundation: Travel through ordinary space could proceed at no rate more rapid than that of ordinary light… and that would have meant years of travel between even the nearest of inhabited systems. Through hyper-space, that unimaginable region that was neither space nor time, matter nor energy, something nor nothing, one could traverse the length of the Galaxy in the interval between two neighbouring instants of time. What the heck is Asimov talking about? Did he know something about a secret theory of faster-than-light travel? Hardly. Asimov was participating in a grand science fiction tradition: when confronted with an immovable obstacle to your story, make something up. The problem is that as far as we know, faster-than-light travel is impossible, making galactic empires, federations, confederacies and any other cross-galaxy civilizations impossible. But that’s so inconvenient. To evade the cosmic speed limit science fiction has created “warp-drives,” “hyperspace,” “subspace,” and other tricks that have become so ingrained, fans of science fiction don’t give them a second thought. -
Some Thoughts on Faster-Than-Light (FTL) Travel
12 Propulsion and Energy Forum AIAA 2016-4918 July 25-27, 2016, Salt Lake City, UT 52nd AIAA/SAE/ASEE Joint Propulsion Conference Destination Universe: Some Thoughts on Faster-Than-Light (FTL) Travel Gary L. Bennett* Metaspace Enterprises Faster-than-light (FTL) travel is a staple of science fiction and it has been seriously investigated by a number of physicists. Despite the challenges both theoretical and practical, the idea of FTL travel is intriguing because if it can be achieved it offers the human race the chance to travel to the stars within the lifetimes of the crew. Three of the principal FTL concepts are discussed in this paper: (1) tachyons which are hypothetical FTL particles with properties consistent with the special theory of relativity; (2) wormholes which offer a window to distant star systems using general relativity; and (3) warp drives which employ general relativity to modify spacetime to get around the velocity of light speed limit. Issues facing hypothetical FTL travelers are discussed. In space there are countless constellations, suns and planets; we see only the suns because they give light; the planets remain invisible, for they are small and dark. There are also numberless earths circling around their suns, no worse and no less than this globe of ours. For no reasonable mind can assume that heavenly bodies that may be far more magnificent than ours would not bear upon them creatures similar or even superior to those upon our human earth. ---Giordano Bruno (1548 – 1600) Burned at the stake for heresy (17 February 1600) 1. Introduction The stars have beckoned the human race since before the dawn of history. -
General Relativity and Gravitational Waveforms
General Relativity and Gravitational Waveforms Deirdre Shoemaker Center for Relativistic Astrophysics School of Physics Georgia Institute of Technology Kavli Summer Program in Astrophysics 2017 Astrophysics with Gravitational Wave Detections Copenhagen Niels Bohr Institute Deirdre Shoemaker General Relativity and Gravitational Waveforms References Spacetime And Geometry: An Introduction To General Relativity, Sean Carroll, Pearson (2016), ISBN-10: 9332571651, ISBN-13: 978-9332571655 Gravity: An Introduction to Einstein’s General Relativity, James B. Hartle, Pearson (2003), ISBN-10: 0805386629, ISBN-13: 978-0805386622 Numerical Relativity: Solving Einstein’s Equations on a Computer. Thomas Baumgarte and Stuart Shapiro, Cambridge University Press, ISBN: 9780521514071 Introduction to 3+1 Numerical Relativity. Miguel Alcubierre, Oxford University Press, ISBN 13:9780199205677 Relativistic Hydrodynamics. Luciano Rezzolla, Oxford University Press, ISBN: 978-0-19-852890-6 Astro-GR Online Course on GWs http://astro-gr.org/online-course-gravitational-waves/ 2nd Fudan Winter School on Astrophysics Black Holes Pablo Laguna’s and DS’s Courses http://bambi2017.fudan.edu.cn/bh2017/Program.html Deirdre Shoemaker General Relativity and Gravitational Waveforms Goals By the end of these three lectures, I intend for you to understand the connection between the gravitational waveform seen in the figure to Einstein’s General Theory of Relativity, recognize the techniques employed to predict theoretical gravitational wavesforms, and what the best use practices are for each, and develop some intuition on how the waveform depends on the physical parameters of the black holes. Deirdre Shoemaker General Relativity and Gravitational Waveforms Lecture 1: General Relativity Lecture 1: General Relativity Gravity as Geometry Where do gravitational wave come from? Hint: Einstein is the stork. -
Annual Report 2001
Annual Report 2001 Max-Planck-Institut für Gravitationsphysik Albert-Einstein-Institut Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. Preface by the Managing Director The annual report 2001 reviews the important developments that took place over the past year at the Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut). Most prominent among these were the enlargement of the institute by two experimental divisions in Hannover, the appointments of two new directors, Gerhard Huisken and Karsten Danzmann, with the appointment of a second director for the Hannover Teilinstitut still pending, and the third meeting of the AEI Fachbeirat, our external scientific review committee, in September 2001. With its three theoretical and two experimental sections, AEI will cover an unusually broad range of subjects, ranging from pure mathematics over string theory and quantum gravity, and numerical relativity and its astrophysical applications all the way to the mechanics and control of gravitational wave detectors and quantum optics devices. To run such an institute will be an interesting experience and a mighty challenge for the future! With the appointment of Gerhard Huisken to become head of the Geo- metric Analysis and Gravitation division, the long search for a successor to our founding director Jürgen Ehlers (now "director emeritus") was at last brought to a happy end. Gerhard Huisken, an eminent mathe- matician, is known worldwide for his numerous contributions to pure mathematics and mathematical physics, in particular -
Hyper Fast Interstellar Travel Within General Relativity:The Alcubierre and Natario Warp Drive Spacetimes:From Science Fiction to Science Fact Fernando Loup
Hyper Fast Interstellar Travel Within General Relativity:The Alcubierre and Natario Warp Drive Spacetimes:From Science Fiction to Science Fact Fernando Loup To cite this version: Fernando Loup. Hyper Fast Interstellar Travel Within General Relativity:The Alcubierre and Natario Warp Drive Spacetimes:From Science Fiction to Science Fact. 2013. hal-00827161 HAL Id: hal-00827161 https://hal.archives-ouvertes.fr/hal-00827161 Submitted on 28 May 2013 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Hyper Fast Interstellar Travel Within General Relativity:The Alcubierre and Natario Warp Drive Spacetimes:From Science Fiction to Science Fact Fernando Loup ∗ Residencia de Estudantes Universitas Lisboa Portugal May 28, 2013 Abstract Warp Drives are solutions of the Einstein Field Equations that allows superluminal travel within the framework of General Relativity.There are at the present moment two known solutions: The Alcubierre warp drive discovered in 1994 and the Natario warp drive discovered in 2001.The warp drive seems to be very attractive because allows