The Physical Basis of The Direction of Time (eBook)

H. Dieter Zeh studied physics in Brunswick and Heidelberg, where he began work on theoretical nuclear physics. After a year of research at the California Institute of Technology, he moved to the University of California in San Diego to work on the synthesis of the heavy elements, before returning to the University of Heidelberg, where he later became professor of theoretical physics. His studies of collective motion in nuclei led him to address the quantum-to-classical transition in general, and in particular the quantum measurement problem, which is in turn related to many aspects of irreversibility (arrows of time). During this work, Zeh recognized and formulated the universal and unavoidable role of uncontrollable quantum entanglement, thus becoming a founder of the area now known as decoherence.

Preface 6
Contents 8
Introduction 10
1 The Physical Concept of Time 19
2 The Time Arrow of Radiation 25
2.1 Retarded and Advanced Form of the Boundary Value Problem 28
2.2 Thermodynamical and Cosmological Properties of Absorbers 32
2.3 Radiation Damping 36
2.4 The Absorber Theory of Radiation 42
3 The Thermodynamical Arrow of Time 47
3.1 The Derivation of Classical Master Equations 51
3.2 Zwanzig’s General Formalism of Master Equations 65
3.3 Thermodynamics and Information 76
3.4 Semigroups and the Emergence of Order 85
3.5 Cosmic Probabilities and History 90
4 The Quantum Mechanical Arrow of Time 93
4.1 The Formal Analogy 94
4.2 Ensembles Versus Entanglement 102
4.3 Decoherence 109
4.4 Quantum Dynamical Maps 123
4.5 Exponential Decay and ‘Causality’ in Scattering 127
4.6 The Time Arrow in Various Interpretations of Quantum Theory 132
5 The Time Arrow of Spacetime Geometry 143
5.1 Thermodynamics of Black Holes 147
5.2 Thermodynamics of Acceleration 156
5.3 Expansion of the Universe 161
5.4 Geometrodynamics and Intrinsic Time 169
6 The Time Arrow in Quantum Cosmology 179
6.1 Phase Transitions of the Vacuum 183
6.2 Quantum Gravity and the Quantization of Time 185
Epilog 206
Appendix: A Simple Numerical Toy Model 210
References 216
Index 234