Causality, 4-Geons and Dark Energy: a Radical View of Space-Time R.E.S
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5 VII July 2017
5 VII July 2017 International Journal for Research in Applied Science & Engineering Technology (IJRASET) ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887 Volume 5 Issue VII, July 2017- Available at www.ijraset.com An Introduction to Time Travel Rudradeep Goutam Mechanical Engg. Sawai Madhopur College of Engineering & Technology, Sawai Madhopur ,.Rajasthan Abstract: Time Travel is an interesting topic for a Human Being and also for physics in Ancient time, The Scientists Thought that the time travel is not possible but after the theory of relativity given by the Albert Einstein, changes the opinion towards the time travel. After this wonderful Research the Scientists started to work on making a Time Machine for Time Travel. Stephon Hawkins, Albert Einstein, Frank j. Tipler, Kurt godel are some well-known names who worked on the time machine. This Research paper introduce about the different ways of Time Travel and about problems to make them practically possible. Keywords: Time travel, Time machine, Holes, Relativity, Space, light, Universe I. INTRODUCTION After the discovery of three dimensions it was a challenge for physics to search fourth dimension. Quantum physics assumes The Time as a fourth special dimension with the three dimensions. Simply, Time is irreversible Succession of past to Future through the present. Science assumes that the time is unidirectional which is directed past to future but the question arise that: Is it possible to travel in Fourth dimension (Time) like the other three dimensions? The meaning of time Travel is to travel in past or future from present. The present is nothing but it is the link between past and future. -
You Zombies, Click and a Novel, 1632, Both of Which Are Available Online from Links in the Handout
Instructor's notes to F402 Time Travel in Science Fiction Session 1 – Introduction Welcome to F402, Time Travel in Science Fiction. The objective of this course is to help you to read, understand and enjoy stories in the genre. The course is in two parts; the first is Today's lecture and discussion on the genre while the second is class discussions of two stories of opposite types. click The reading assignment consists of a short story, All You Zombies, click and a novel, 1632, both of which are available online from links in the handout. click For the convenience of those who prefer dead trees, I have listed a number of anthologies1 containing All You Zombies. Reading Assignment for Sessions 2-3 click All You Zombies is one of two tour de force stories by Robert A. Heinlein that left their mark on the genre for decades. Please read All You Zombies prior to the next session click and 1632 click click Part One, chapters 1-14 prior to the third session. Esc Session 1 Keep in mind that science fiction is a branch of literature, so the normal criteria of, e.g., characterization, consistency, continuity, plot structure, style, apply; I welcome comments, especially from those who have expertise in those areas. In addition, while a science fiction author must rely on the willing suspension of disbelief, he should do so sparingly. There is a lapse of continuity in 1632 between chapters 8 and 9; see whether you can spot it. I will suggest specific discussion points to start each discussion, but please bring up any other issues that you believe to be important or interesting. -
On Closed Timelike Curves, Cosmic Strings and Conformal Invariance Tuesday, 8 October 2019 12:00 (20 Minutes)
The Time Machine Factory [unspeakable, speakable] on Time Travel -TM2019 Contribution ID: 1 Type: talk On Closed Timelike Curves, Cosmic Strings and Conformal Invariance Tuesday, 8 October 2019 12:00 (20 minutes) Abstract In general relativity theory (GRT) one can construct solutions which are related to real physical objects. The most famous one is the black hole solution. One now believes that in the center of many galaxies there is a rotating super-massive black hole, the Kerr black hole. Because there is an axis of rotation, the Kerr solution is a member of the family of the axially symmetric solutions of the Einstein equations. A legitimate ques- tion could be: are there other axially or cylindrically symmetric asymptotically flat solutions of the equations of Einstein with a classical or non-classical matter distribution and with correct asymptotical behavior, just as the Kerr solution? Many attempts are made, such as the Weyl-, Papapetrou- and Van Stockum solution. None of these attempts result is physically acceptable solution. Often, these solutions possess closed timelike curves (CTC’s). The possibility of the formation of CTC’s in GRT seems to be an obstinate problem tosolve in GRT. At first glance, it seems possible to construct in GRT causality violating solutions. CTC’s suggestthe possibility of time-travel with its well-known paradoxes. Although most physicists believe that Hawking’s chronology protection conjecture holds in our world, it can be alluring to investigate the mathematical under- lying arguments of the formation of CTC’s. There are several spacetimes that can produce CTC’s. Famous is the Tipler-cylinder. -
The Blue Box White Paper
The Blue Box White Paper Doctor Benjamin K. Tippetta Gallifrey Polytechnic Institute Doctor David Tsangb Gallifrey Institute of Technology (GalTech) (Dated: October 31, 2013) This white paper is an explanation of Ben and Dave’s TARDIS time machine, written for laypeople who are interested in time travel, but have no technical knowledge of Einstein’s Theory of General Relativity. The first part of this paper is an introduction to the pertinent ideas from Einstein’s theory of curved spacetime, followed by a review of other popular time machine spacetimes. We begin with an intro- duction to curvature and lightcones. We then explain the Alcubierre Warp Drive, the Morris-Thorne wormhole, and the Tipler cylinder. We then describe the Traversable Achronal Retrograde Domain in Spacetime (TARDIS), and ex- plain some of its general properties. Our TARDIS is a bubble of spacetime curvature which travels along a closed loop in space and time. A person travelling within the bubble will feel a constant acceleration. A person outside of the TARDIS will see two bubbles: one which is evolving forwards in time, and one which is evolving backwards in time. We then discuss the physical limitations which may prevent us from ever constructing a TARDIS. Finally, we discuss the method through which a TARDIS can be used to travel between arbitrary points in space and time, and the possible dangers involved with exiting a TARDIS from the wrong side. Before we begin, would you like a Jelly Baby? arXiv:1310.7983v1 [physics.pop-ph] 29 Oct 2013 a email: [email protected] b email: [email protected] 2 Figure 1: We ask K9 to steer straight-ahead as he moves over the curved ground of an old quarry in Wales. -
Bayanebartar.Org
Today we're going to talk a little bit more technically about what exactly is time like if we're going to travel through it we probably should know what it is right we're also going to talk about whether or not time travel is going to be possible and the consequences of what would happen if we travel through time and whether we've already time traveled there's a lot to talk about that's why we have four episodes this week which I'm super excited about but today first let's talk about whether time travel is possible so if you're going to travel on something or through something or whatever kind of the first step is knowing what it is if I'm a build a boat to sail on a lake I probably need to understand water so BayaneBartar.org that's what we're talking about and the problem with time travel is we don't really have a lot of definition of what time is because to be honest a minute a second an hour days it's all relative depending on what planet you're on and depending on your experience we invented the idea of time time is our perception of things right it's how we divide ourselves in our lives in our you know days but all of that is completely relative so what is time on a bigger question needs to be answered before we can travel through it and many people have been trying to answer this for a long long time and there are so many aspects to think about when considering time or explaining time but where I always start is the super simple easy to understand second law of thermodynamics I'm sure I don't have to tell you guys the first law -
Blackholeswormholesandtimemachines.Pdf
B LACK H OLES WORMHOLES &TIME M ACHINES CONTENTS PREFACE ix ACKNOWLEDGMENTS xiii INTRODUCTION xv SPACE 1 THE 4TH DIMENSION 3 To do with shapes • What is space? • 2Dworld and 2D’ers • Curved space • Is there really a fourth dimension? 2 MATTERS OF SOME GRAVITY 22 Apples and moons • Einstein’s gravity • Free fall • Rubber space • Twinkle, twinkle • Cooking the elements • Champagne supernovae in the sky 3 THE UNIVERSE 41 The night sky • How big is the Universe? • The expanding Universe • Hubble, bubble . • Space is stretching • Did the Big Bang really happen? • The edge of space • A closed universe • An open universe • What shape is the Universe then? • Invisible matter • 1998: a big year in cosmology • Is the Universe infinite? • Why is it dark at night? • Before the Big Bang? • Summary 4 BLACK HOLES 78 More to light than meets the eye! • Invisible stars • Beyond the horizon • A hole that can never be filled • Spinning black holes • Falling into a black hole • To see a black hole • Not so black after all • White holes vii BLACK HOLES, WORMHOLES & TIME MACHINES TIME 5 TIMES ARE CHANGING 111 What is time? • Who invented time? • The first moment • Does time flow? • Something called entropy • Arrows of time • Stephen Hawking gets it wrong • A possible solution 6 EINSTEIN’S TIME 139 What is so special about special relativity? • The two faces of light • Thought experiments and brain teasers • Slowing down time • Shrinking distances • Light—the world speed record • When time runs backwards • Little green men • Fast forward to the future • Spacetime—the -
A Study of Temporal Metaphysics Through Hard Science Fiction and Its Restrictions on the Past and Future Lindsey E
Oglethorpe Journal of Undergraduate Research Volume 2 | Issue 2 Article 2 August 2013 Shadows in Time: A Study of Temporal Metaphysics through Hard Science Fiction and its Restrictions on the Past and Future Lindsey E. Mitchell Oglethorpe University, [email protected] Follow this and additional works at: https://digitalcommons.kennesaw.edu/ojur Part of the Cosmology, Relativity, and Gravity Commons, Fiction Commons, and the Other Physics Commons Recommended Citation Mitchell, Lindsey E. (2013) "Shadows in Time: A Study of Temporal Metaphysics through Hard Science Fiction and its Restrictions on the Past and Future," Oglethorpe Journal of Undergraduate Research: Vol. 2 : Iss. 2 , Article 2. Available at: https://digitalcommons.kennesaw.edu/ojur/vol2/iss2/2 This Article is brought to you for free and open access by DigitalCommons@Kennesaw State University. It has been accepted for inclusion in Oglethorpe Journal of Undergraduate Research by an authorized editor of DigitalCommons@Kennesaw State University. For more information, please contact [email protected]. Shadows in Time: A Study of Temporal Metaphysics through Hard Science Fiction and its Restrictions on the Past and Future Cover Page Footnote In Collaboration With Dr. Michael Rulison, Dr. Nicholas Maher, and Dr. Linda Taylor Dedicated To My father, who introduced me to the wonders of science fiction all those years ago and fed my hunger for it with his library of the classics My mother, who has read to me both as a child and an adult, teaching me to write stories that are a joy to read And to my other cherished family and friends, who patiently let me rail about the stupidity of paradoxes and who always inspire me to do better than what I believe myself capable of This article is available in Oglethorpe Journal of Undergraduate Research: https://digitalcommons.kennesaw.edu/ojur/vol2/iss2/2 Mitchell: Shadows in Time Reconciling Science Fiction and Temporal Metaphysics I Two different kinds of science fiction have evolved over time. -
Romero Introduction to Black Hole Astrophysics
Black hole astrophysics Gustavo E. Romero Grupo de Astrofísica Relativista y Radioastronomía Instituto Argentino de Radioastronomía, CONICET-CIC Facultad de Ciencias Astronómicas y Geofísicas, UNLP [email protected], [email protected] What is a star? e What is a star? Eddington proposed (1926): 1.Thermonuclear reactions are the source of energy in the stars 2.The outward pressure of raditation should be taken into account in the equation for equilibrium. What is a star? What is a star? What is a star? What is a star? What is a star? What is a star? The end of stars The end of stars A pair-instability supernova occurs when pair production, the production of free electrons and positrons in the collision between atomic nuclei and energetic gamma rays, reduces thermal pressure inside a supermassive star's core. This pressure drop leads to a partial collapse, then greatly accelerated burning in a runaway thermonuclear explosion which blows the star completely apart without leaving a black hole remnant behind. Pair-instability supernovae can only happen in stars with a mass range from around 130 to 250 solar masses and low to moderate metallicity (low abundance of elements other than hydrogen and helium, a situation common in Population III stars). Oppenheimer & Snyder (1939): non-stopping collapse. Collapse to what? The answer is in General Relativity. Black holes Albert Einstein John A. Wheeler Letter from Karl Schwarzschild to Einstein, 22 December 1915 Schwarzschild is one of the few astronomers who are interested in Einstein's General Theory of Relativity. In December 1915, he is based at the Russian front line. -
17. Time Travel 2 1
Topics: 17. Time Travel 2 1. MTY Traversible Wormnhole 2. Ori-Soen Spacetime 3. Gödel Spacetime Def. 1. A time travel spacetime is a solution to the 4. Tipler Cylinder Spacetime 5. Gott Cosmic String Spacetime Einstein equations that admits closed timelike curves (CTCs). Def. 2. A time machine spacetime is a time travel spacetime in which the CTCs are generated by the operation of a device (the time machine). • All of the following are time travel spacetimes. - Whether or not some are, in addition, time machine spacetimes is still open to debate. 1 - Morris, M. and K. Thorne (1988) 'Wormholes in spacetime and 1. MTY Traversible Wormhole their use for interstellar travel', Am. J. Phys. 56, 395. - Morris, M., K. Thorne, U. Yurtserver (1988) 'Wormholes, time machines and the weak energy condition', Phys. Rev. D 49, 3990. • Recall the Einstein-Rosen wormhole: It doesn't stay open long enough. • C IV γ I B A • A B C • A worldline γ connecting two points in I and IV during the time the wormhole is open must at some point become spacelike. 2 - Morris, M. and K. Thorne (1988) 'Wormholes in spacetime and 1. MTY Traversible Wormhole their use for interstellar travel', Am. J. Phys. 56, 395. - Morris, M., K. Thorne, U. Yurtserver (1988) 'Wormholes, time machines and the weak energy condition', Phys. Rev. D 49, 3990. • Recall the Einstein-Rosen wormhole: It doesn't stay open long enough. • • C IV γ I γ B A • • • A worldline γ connecting two points in I and IV during the time the wormhole is open must at some point become spacelike. -
The Light of the TARDIS
The Light of the TARDIS Lars Christian Hauge Thesis submitted for the degree of Master of Science in Astronomy Institute of Theoretical Astrophysics University of Oslo 1 June 2015 ii Abstract In 2013 a new metric called TARDIS was introduced. This metric was published by Tippet and Tsang, and described a time machine. This thesis uses numerical methods to explore properties of this new metric. We start by visualizing geodesics in two and three dimensions, then we see that there is a really high blueshift when the light rays hit the borders of our time machine, but when we drop an approximation made by Tippet and Tsang, we find that the blueshift almost disappears. We use the Darmois-Israel junction conditions to see that it is possible for this time machine to travel anywhere in time and space. Finally, we calculate the energy-momentum tensor corresponding to this metric and find that it requires exotic matter, which makes it hard to construct this time machine in real life. iii iv Acknowledgements \There's a lot of things you need to get across this universe. Warp drive... wormhole refractors... You know the thing you need most of all? You need a hand to hold." - The Doctor, Season 6, Episode 6 Firstly, I would like to thank my supervisor Øystein Elgarøy for the interesting thesis topic, for his valueable help and for always having time to see me. The work would have been so much harder without his dedication and enthusiasm. Also I would like to thank Realistforeningen for making the years I have spent studying fun and exciting. -
STATIC and DYNAMIC TRAVERSABLE WORMHOLES By
STATIC AND DYNAMIC TRAVERSABLE WORMHOLES by JAROSLAW PAWEL ADAMIAK submitted in part fulfilment of the requirements for the degree of MASTER OF SCIENCE in the subject APPLIED MATHEMATICS at the UNIVERSITY OF SOUTH AFRICA SUPERVISOR: PROF N T BISHOP JOINT SUPERVISOR: PROF W M LESAME JANUARY 2005 Abstract The aim of this work is to discuss the effects found in static and dynamic wormholes that occur as a solution of Einstein equations in general relativity. The ground is prepared by presentation of “faster than light” effects, historical perspective, worm- hole definition and contemporary directions in wormhole research. Then the focus is narrowed to Morris-Thorne framework for static spherically symmetric wormhole. Energy conditions being a fundamental component in wormhole physics are discussed in detail, their definition, most common violations and attempts to exotic matter quantification. Two types of dynamic wormholes, evolving and rotating, together with their variations are considered. Computer algebra and Cartan calculus are used to obtain detailed solutions. i Contents 1 Introduction 1 1.1 Faster Than Light Mechanisms . 1 1.2 Historical Perspective . 9 1.3 Concept of a Wormhole . 12 1.4 Current State of Research . 15 2 Morris-Thorne Framework 20 2.1 Desired Properties of Traversable Wormhole . 20 2.2 Metric and Einstein Field Equations . 22 2.3 Traversability Conditions . 26 2.4 Wormhole Examples . 31 2.4.1 Zero radial tides . 32 2.4.2 Zero density . 34 3 Energy Conditions 36 3.1 Pointwise and Averaged Energy Conditions . 36 3.2 Violations . 41 ii CONTENTS iii 3.3 Quantification of exotic matter . -
Black Holes Wormholes
B LACK H OLES WORMHOLES &TIME M ACHINES J IM A L -KHALILI University of Surrey Institute of Physics Publishing Bristol and Philadelphia B LACK H OLES WORMHOLES &TIME M ACHINES About the Author Jim Al-Khalili was born in 1962 and works as a theoretical physicist at the University of Surrey in Guildford. He is a pioneering popularizer of science and is dedicated to conveying the wonder of science and to demystifying its frontiers for the general public. He is an active member of the Public Awareness of Nuclear Science European committee. His current research is into the properties of new types of atomic nuclei containing neutron halos. He obtained his PhD in theoretical nuclear physics from Surrey in 1989 and, after two years at University College London, returned to Surrey as a Research Fellow before being appointed lecturer in 1992. He has since taught quantum physics, relativity theory, mathematics and nuclear physics to Surrey undergraduates. He is married with two young children and lives in Portsmouth in Hampshire. c IOP Publishing Ltd 1999 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the publisher. Multiple copying is permitted in accordance with the terms of licences issued by the Copyright Licensing Agency under the terms of its agreement with Universities UK (UUK). British Library Cataloguing-in-Publication Data A catalogue record for this book