Time machines : time travel in physics, metaphysics, and science fiction

A lively study of how time travel has been portrayed in fiction from the 18th century to the present. The author also discusses how modern physicists are now giving serious attention to what was once dismissed as sheer fantasy. Technical appendices, using only first college calculus, are supplied for those with a mathematical bent. This book is intended for general science readers. Cover......Page Front_0001.djvu Time Machines: Time Travel in Physics, Metaphysics, and Science Fiction......Page 0004_0001.djvu Copyright......Page 0005_0001.djvu A Sample of Things to Come......Page 0008_0001.djvu Contents......Page 0010_0001.djvu Prologue......Page 0012_0001.djvu The Mystery of Time Travel......Page 0020_0001.djvu Machineless Time Travel Without Dreams or Drugs......Page 0027_0001.djvu Time Travel by Machine......Page 0030_0001.djvu H. G. Wells - Why His Time Machine Won't Work......Page 0032_0001.djvu Traveling to the Future......Page 0035_0001.djvu Traveling to the Past......Page 0036_0001.djvu Who Else Might Be Interested in Time Travel......Page 0040_0001.djvu Some Problems......Page 0043_0001.djvu Backward in Time - Can It Really Be Done?......Page 0045_0001.djvu The Problem of Paradoxes......Page 0048_0001.djvu The Fictional Origins of \"Change the Past\"......Page 0053_0001.djvu Ways to Avoid Paradoxes......Page 0055_0001.djvu Where Are All the Time Travelers?......Page 0062_0001.djvu Skepticism and Time Travelers......Page 0066_0001.djvu Einstein, Godel, and the Past......Page 0072_0001.djvu Quantum Mechanics, Black Holes, Singularities, and Time Travel......Page 0077_0001.djvu Tipler's Time Machine......Page 0081_0001.djvu What is Time?......Page 0084_0001.djvu Speculations on the Reality of Time......Page 0088_0001.djvu Has the Past Been for Ever?......Page 0093_0001.djvu Time and Clocks......Page 0097_0001.djvu Hyperspace and Wormholes......Page 0099_0001.djvu Monsters in Hyperspace......Page 0104_0001.djvu Space as the Fourth Dimension......Page 0108_0001.djvu Time as the Fourth Dimension......Page 0115_0001.djvu H. G. Wells on Space and Time......Page 0117_0001.djvu Spacetime and the Fourth Dimension......Page 0120_0001.djvu Spacetime, Omniscience, and Free Will......Page 0131_0001.djvu The Language of Time Travel......Page 0142_0001.djvu Does Time Have a Direction?......Page 0144_0001.djvu Cause and Effect......Page 0146_0001.djvu What Does \"Now\" Mean?......Page 0155_0001.djvu Irreversibility......Page 0160_0001.djvu Worlds in Reverse......Page 0163_0001.djvu The Philosophy and Physics of Reversed Time......Page 0173_0001.djvu Entropy as Time's Arrow......Page 0175_0001.djvu Other Arrows of Time......Page 0181_0001.djvu Multidimensional Time......Page 0183_0001.djvu Paradoxes......Page 0186_0001.djvu Early Science Fiction Speculations on Time-Travel Paradoxes......Page 0189_0001.djvu Two Basic Time - Travel Paradoxes......Page 0193_0001.djvu Can the Present Change the Past? Can the Past Be Un-Done?......Page 0195_0001.djvu Changing vs. Affecting the Past......Page 0202_0001.djvu Why Can't a Time Traveler Kill His Grandfather?......Page 0212_0001.djvu Quantum Mechanics and Time Travel......Page 0220_0001.djvu Causal Loops......Page 0224_0001.djvu Sexual Paradoxes......Page 0233_0001.djvu Maxwell's Equations and Advanced Effects......Page 0236_0001.djvu Communication with the Past......Page 0239_0001.djvu Wheeler and Feynman and Their Bilking Paradox......Page 0243_0001.djvu Absorber Theory and Signaling to the Past......Page 0246_0001.djvu Tachyonic Signals, Spooky Actions, and the Bell Antitelephone......Page 0250_0001.djvu Epilogue......Page 0260_0001.djvu Notes and References......Page 0268_0001.djvu 1 What Time Is Now?......Page 0306_0001.djvu 2 Time Dilation via the Photon Clock......Page 0312_0001.djvu 3 The Lorentz Transformation......Page 0316_0001.djvu 4 Spacetime Diagrams, Light Cones, Metrics, and Invariant Intervals......Page 0324_0001.djvu 5 Proper Time, Curved World Lines, and the Twin Paradox......Page 0336_0001.djvu 6 A High-Speed Rocket Is A One-Way Time Machine to the Future......Page 0342_0001.djvu 7 Superluminal Speeds and Backward Time Travel......Page 0348_0001.djvu 8 Backward Time Travel According to Godel and Tipler......Page 0356_0001.djvu 9 The Wormhole Time Machine......Page 0360_0001.djvu Bibliography......Page 0372_0001.djvu Index......Page 0422_0001.djvu Time Machines Explores The History Of Time Travel In Fiction; The Fundamental Scientific Concepts Of Time, Spacetime, And The Fourth Dimension; The Speculations Of Einstein, Richard Feynman, Kurt Godel, And Others; Scientific Hypotheses About The Direction Of Time, Reversed Time, And Multidimensional Time; Time-travel Paradoxes, And Much More. Time Machines Is Highly Readable Even For Those With No Physics Background. The Text Contains No Equations Or Higher Calculus: All The Mathematics Are Contained In Appendices That Require Nothing Beyond Differential And Integral Calculus. Time Machines Contains The Most Extensive Bibliography Available On The Fictional And Scientific Literature Of Time Travel.--book Jacket. Ch. 1. An Overview Of Time Travel -- Ch. 2. On The Nature Of Time, Spacetime, And The Fourth Dimension -- Ch. 3. The Arrows Of Time -- Ch. 4. Time-travel Paradoxes And (some Of) Their Explanations. Paul J. Nahin. Includes Bibliographical References (p. [353]-402) And Index.