Time's Arrow & Archimedes' Point: Contents

Time's Arrow & Archimedes' Point

Contents

1.

The View from Nowhen

3

Outline of the book  5    Remarks on style  11    The stock philosophical debates about time  12    The arrows of time  16    The puzzle of origins  17

2.

"More Apt to Be Lost than Got": The Lessons of the Second Law

22

Irreversibility discovered: Newton to Boltzmann  23    The reversibility objection I  27    Entropy as probability  29    The reversibility objection II  31    Boltzmann's symmetric view  32    Do we need to explain why entropy increases?  37    The role of the H-theorem  40    Does chaos theory make a difference?  43    Branch systems  44    Could entropy eventually decrease?  46    Summary  47

3.

New Light on the Arrow of Radiation

49

The circular wave argument  54    Radiation and banking  58    Radiation and nonfrictionless banking  60    What would time-symmetric radiation look like?  61    The Wheeler-Feynman theory in brief  65    Why doesn't the argument work in reverse?  67    Are the components distinct?  69    The new interpretation  70    Why the apparent asymmetry?  71    No need for a future absorber  73    Related issues in physics  73    Summary  76

4.

Arrows and Errors in Contemporary Cosmology

78

The need for smoothness  79    Gold universes and the basic dilemma  81    Smoothness: how surprising is it?  82    The appeal to inflation  85    Hawking and the big crunch  86    The basic dilemma and some ways to avoid it  93    What's wrong with a Gold universe?  99    A telescope to look into the future?  105    Conclusion  111

5.

Innocence and Symmetry in Microphysics

114

Conflicting intuitions in contemporary physics  116    Preinteractive "innocence": the intuitive asymmetry  118    Two kinds of innocence in physics  120    Is µInnocence observable?  121    Symmetry or innocence?  123    µInnocence and quantum mechanics  124    µInnocence and backward causation  127    The next step  129

6.

In Search of the Third Arrow

132

Causal asymmetry: the nature of the problem  136    A third arrow?  138    The fork asymmetry  138    Too few forks  140    Two ways to misuse a fork  142    A fourth arrow?  146    The symmetry of micro-forks  147    Two extreme proposals  152    The perspectival view  155    Escaping a circle, projecting an arrow  159    Summary  161

7.

Convention Objectified and the Past Unlocked

162

Asymmetry conventionalized  163    Convention objectified  166    The asymmetry of agency  168    The role of counterfactuals  169    Could the past depend on the future?  170    Escaping the paradoxes of backward causation  171    The past unlocked  174    Advanced action: its objective core  177    Counterfactuals: what should we fix?  178    Advanced action and µInnocence  179    Is µInnocence merely conventional?  181    Why can't a photon be more like a billiard ball?  183    Symmetry and advanced action I  185    Symmetry and advanced action II  187    Taxonomy and T-symmetry  189    Backward causation: not forward causation backwards  190    Inverted forks and distant effects  191    Summary: saving the baby  192

8.

Einstein's Issue: The Puzzle of Contemporary Quantum Theory

195

The quantum view: basic elements  197    A TOM SPLIT IN THOUGHT EXPERIMENT!  198    The EPR argument  201    EPR and special relativity: the cost of nonlocality  204    The temporal asymmetry objection  206    The consequences of superposition  209    Bell's Theorem  212    EPR for triplets: the GHZ argument  217    What if there is no collapse?  219    Many minds?  222    The decoherence approach  225    Summary: Einstein's live issue  228

9.

The Case for Advanced Action

231

Outline of the chapter  233    Locality, independence, and the pro-liberty Bell  235    Locality saved in the past  236    Locality saved in the future  238    Was Bell told?  241    The benefits of backward forks  242    Advanced action in quantum mechanics  246    Einstein reissued?  248    Advanced action and the GHZ argument  251    Advanced action and superposition  252    The atemporal view  257

Overview

261

Main conclusions of the book  262    Directions for further work  266    Why it matters  266

Notes

269

Bibliography

285

Index

293

Last updated 1 September, 1996.

1.	The View from Nowhen	3
	Outline of the book 5 Remarks on style 11 The stock philosophical debates about time 12 The arrows of time 16 The puzzle of origins 17

2.	"More Apt to Be Lost than Got": The Lessons of the Second Law	22
	Irreversibility discovered: Newton to Boltzmann 23 The reversibility objection I 27 Entropy as probability 29 The reversibility objection II 31 Boltzmann's symmetric view 32 Do we need to explain why entropy increases? 37 The role of the H-theorem 40 Does chaos theory make a difference? 43 Branch systems 44 Could entropy eventually decrease? 46 Summary 47

3.	New Light on the Arrow of Radiation	49
	The circular wave argument 54 Radiation and banking 58 Radiation and nonfrictionless banking 60 What would time-symmetric radiation look like? 61 The Wheeler-Feynman theory in brief 65 Why doesn't the argument work in reverse? 67 Are the components distinct? 69 The new interpretation 70 Why the apparent asymmetry? 71 No need for a future absorber 73 Related issues in physics 73 Summary 76

4.	Arrows and Errors in Contemporary Cosmology	78
	The need for smoothness 79 Gold universes and the basic dilemma 81 Smoothness: how surprising is it? 82 The appeal to inflation 85 Hawking and the big crunch 86 The basic dilemma and some ways to avoid it 93 What's wrong with a Gold universe? 99 A telescope to look into the future? 105 Conclusion 111

5.	Innocence and Symmetry in Microphysics	114
	Conflicting intuitions in contemporary physics 116 Preinteractive "innocence": the intuitive asymmetry 118 Two kinds of innocence in physics 120 Is µInnocence observable? 121 Symmetry or innocence? 123 µInnocence and quantum mechanics 124 µInnocence and backward causation 127 The next step 129

6.	In Search of the Third Arrow	132
	Causal asymmetry: the nature of the problem 136 A third arrow? 138 The fork asymmetry 138 Too few forks 140 Two ways to misuse a fork 142 A fourth arrow? 146 The symmetry of micro-forks 147 Two extreme proposals 152 The perspectival view 155 Escaping a circle, projecting an arrow 159 Summary 161

7.	Convention Objectified and the Past Unlocked	162
	Asymmetry conventionalized 163 Convention objectified 166 The asymmetry of agency 168 The role of counterfactuals 169 Could the past depend on the future? 170 Escaping the paradoxes of backward causation 171 The past unlocked 174 Advanced action: its objective core 177 Counterfactuals: what should we fix? 178 Advanced action and µInnocence 179 Is µInnocence merely conventional? 181 Why can't a photon be more like a billiard ball? 183 Symmetry and advanced action I 185 Symmetry and advanced action II 187 Taxonomy and T-symmetry 189 Backward causation: not forward causation backwards 190 Inverted forks and distant effects 191 Summary: saving the baby 192

8.	Einstein's Issue: The Puzzle of Contemporary Quantum Theory	195
	The quantum view: basic elements 197 A TOM SPLIT IN THOUGHT EXPERIMENT! 198 The EPR argument 201 EPR and special relativity: the cost of nonlocality 204 The temporal asymmetry objection 206 The consequences of superposition 209 Bell's Theorem 212 EPR for triplets: the GHZ argument 217 What if there is no collapse? 219 Many minds? 222 The decoherence approach 225 Summary: Einstein's live issue 228

9.	The Case for Advanced Action	231
	Outline of the chapter 233 Locality, independence, and the pro-liberty Bell 235 Locality saved in the past 236 Locality saved in the future 238 Was Bell told? 241 The benefits of backward forks 242 Advanced action in quantum mechanics 246 Einstein reissued? 248 Advanced action and the GHZ argument 251 Advanced action and superposition 252 The atemporal view 257

	Overview	261
	Main conclusions of the book 262 Directions for further work 266 Why it matters 266