by Paul Davies
Hafele-Keating experiment 10, 11, 12
Haldane, J. B. S. 5
Hawking, Stephen 96, 97,124, 135
heat radiation 36, 96
Heisenberg uncertainty principle 82, 83, 84, 91, 117
Higgs field 88
Hitler, Adolf 106
hydrogen maser clocks 18
imploder 77, 86–8
implosion 20, 41, 42–3, 44, 62
infinite rotating cylinders xi, 39
infinity
infinite density 42, 54, 62, 80;
see also singularities
infinite gravity 42
timewarps 43, 44
inflator 77, 88–95
information for free 113–14, 115,116
Institute for Advanced Studies,
Princeton 36
International Space Station 18
ionized gases 86
Jupiter 95
and Shoemaker-Levy 9 comet 60
Keating, Richard 10, 12
Kerr, Roy xi
kinetic energy 27
Kruskal, Martin 51
Large Electron Positron (LEP) collider 15, 28
laser, creation of negative energy 94–5
law of falling bodies 134
laws of motion (Newton) 117
Levine, Martin 18
levitation 68
light
and black holes 68
light barrier 14, 27–8, 109
motion of 9
speed of 12, 13
squeezing 94
travelling faster than 36, 38–9
and wormholes 68
light waves 43
light years 14
M-theory 135
magnetic fields 86, 87–8
magnetic pinching 86–8
mass
and energy 24, 25, 26
negative 98
Mercator's projection 74
Milky Way
and black holes 41
size of 14
mirrors
and lasers 94–5
moving mirror effect 92, 93
motion
laws of (Newton) 117
perpetual 114, 116
uniform 24
muons 15
naked singularities 63, 82
nagative energy see under energy
negative-energy quantum states xi
negatively charged particles 113
neutron stars 20, 23, 33, 41, 100
neutrons, and quark–gluon plasma 85
Newton, Sir Isaac 2, 3–4, 12, 55, 70, 117
Newtonian mechanics 111
North Pole 46
nuclear fusion 86
nuclear reactions 27
Organisation Européenne de Recherches Nucléaire
(CERN) laboratory, near Geneva 15
parallel realities xi, 120–21
particle accelerators 15, 27–8, 85, 88, 99
past
changing the 105–11
sending signals to 109
past, present and future 3, 4, 5, 28–9
Penrose, Sir Roger 63, 64
perpetual motion 114, 116
photon emitter 108
photons 84
and cosmic strings 129
sent back in time 108
and squeezed light 94
virtual 84–5, 91, 95, 125
Planck, Max 82
Planck energy 88
Planck length 83, 87
Planck time 82, 84, 87
planets, rotating 58
plasmas
low-energy 86
quark–gluon plasma 85, 86, 87
Plato 130
positive energy see under energy
prediction 117
pressure 126–7
probabilities 117
protons
collision with electrons 117, 119–20
and quark-gluon plasma 85
quantum field theory 87
quantum mechanics xi, 82, 110, 116, 117, 120, 123, 134
quantum physics 83, 89
quantum uncertainty 118, 119–20
quantum vacuum 82, 85, 89, 92, 96, 125, 126
quark-gluon plasma 85, 86, 87
quarks 85
radio transmitters 84
radioactive decays 15
relativity theory 4–5, 9, 45, 46, 109, 129
general x, 17–18, 23, 35, 36, 38, 65, 67, 70, 71, 126
special x, 5, 9, 17, 18, 27, 28
Rosen, Nathan 51
see also Einstein-Rosen bridge
Sagan, Carl 66
Contact xi, 65, 72
Sandia National Laboratories, New Mexico 87
satellites, x ray xi
Schrödinger cat paradox 134
Schwarzschild, Karl x, 51, 54, 58, 80
science fiction 1, 3, 14, 65, 104, 123, 133
Shoemaker-Levy 9 comet 60
singularities
in black holes 54–5, 62, 63, 68
cosmic censorship hypothesis 63, 65
edge of spacetime 49, 62, 63, 80
infinite density 42, 54, 62
infinite gravity 42
infinite space curvature 62
naked 63, 82
and quantum effects 83
space
curved 45–6, 54, 62
empty 43–4, 89
and gravity 45, 72
space travel 1
spacecraft, and the speed of light 14
spacetime 55, 56, 57–8, 125
and borrowed energy 82
curved 57–8, 59
flat 57, 71
and singularities 49, 62, 63, 80
spacetime foam 83, 84, 85
spacewarps 46, 48, 49
spaghettification 60, 98
special theory of relativity x, 5, 9, 17, 18, 27, 28
speed
no-faster-than-light rule 14, 31–2, 38
ultra-high 14–15, 33–4
speed of light 13
and spacecraft 14
and subatomic particles 14–15
and timewarps 12, 15
spherical surfaces 74
squeezed the light 94
stars
and black holes 39, 41
compression 20
the nearest 14
neutron 20, 23, 33, 41, 100
subatomic particles 15, 27–8, 87, 99
sun
fate of 41
gravity of 46
spacewarp around the 46, 48
superstrings 135
Szekeres, George 51
tachyons 109–10
Taurus, constellation of 20
telecommunications 29
‘theories of everything’ 135, 136
thermodynamics, second law of 136
Thorne, Kip xi, 67–8, 69, 74, 77, 83, 110, 111
thought experiment 134
time
ancient cultures' view of 3
commonsense notion of 4, 5, 7
Newton's definition 3–4, 12
past, present and future 30–31, 32, 33
relativity of 4–5, 7, 9
reversing 130–32
slowing x, 17–18, 21, 23–4, 43
time dilation x, 12, 13, 15, 24, 29–30, 34, 99, 134
time loops x, 35, 36, 125
time machine factory 77, 78–9
collider 77, 80–86
differentiator 77, 99–100
imploder 77, 86–8
inflator 77, 88–95
other inflator devices 95–6, 98–9
time machines
cosmic string xi, 126–7
wormhole xi, 76, 77,101, 103, 105, 124, 125, 126
time paradoxes
changing the past 105–11
and duplication 111, 113
and information 113–14, 116
time tourists 105
time-loop billiards 110–11
Timeline (film) 3
timelines 31, 32
timewarps
gravitational 22
infinite 43, 44
and speed of light 12, 15
Tipler, Frank xi, 39
topology change 80, 81, 83
twins effect 15–17, 99
uncertainty principle (Heisenberg) 82, 83, 84, 91, 117
uniform motion 24
universe
expansion of 45, 70
gateways to xi other universes xi, 120–21, 122, 123, 135
rotating xi, 36, 38
Unruh, William 96
Van Stockum, W. J. x, 35–6, 126
Vessot, Robert 18
Visser, Matt 95
Wells, H. G. 1, 28, 102
The First Men in the Moon 70
The Time Machine x, 1, 101, 103
Wheeler, John 40
and black holes 41, 51
and spacetime foam 83
and wormholes xi
white dwarfs 41
wormholes x, xi, 39, 45, 51, 73,133
and antigravity 68, 70–71, 72, 88, 89,124
benign 67–8
gravitational field 98
and light 68, 72
origin of 77
as gateway to other universe 51, 54, 67
pinching effect 54,58
and singularities 62, 68
wormholes cont.
throat 51, 54, 58, 62, 68, 72, 95, 124
traversable 58, 65, 67–8, 70–72, 74, 76, 77, 88
virtual 83–4
X ray satellites xi
Z-pinch system 86–7
zero energy 71, 91
Table of Contents
About the Author
Title Page
Copyright Page
Contents
List of illustrations
A brief history of time travel
Prologue
HOW TO BUILD A TIME MACHINE
1: How to visit the future
2: How to visit the past
3: How to build the time machine
4: How to make sense of it all
Epilogue
Bibliography
Index
