Facts of Matter and Light

ISBN-13: 9783031333330 / Twarda / 2023 / 175 str.

Christian Maes

Spis treści

1 The Winners Are . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 Free Fall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.1 Equality of Gravitational and Inertial Mass . . . . . . . . . . . . . . . . . . . . . 8

2.2 Galileo’s Experiments on Free Fall . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2.3 Newton’s Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.3.1 Looking up at the Sky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.3.2 Newton’s Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.4 Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

3 Electromagnetic and Optical Unification . . . . . . . . . . . . . . . . . . . . . . . . . . 21

3.1 Electromagnetic Phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

3.2 Induction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3.3 The Field Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.4 Electromagnetic Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

3.5 Unification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4 Looking at Fluctuations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4.1 Natural Philosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4.2 Atoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.3 Limit theorems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

4.4 Brownian Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

4.4.1 The Random Walk as a Diffusion Model . . . . . . . . . . . . . . . . . 39

4.4.2 Sutherland–Einstein Relation . . . . . . . . . . . . . . . . . . . . . . . . . . 41

4.5 Perrin’s Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

4.6 Fluctuation–Dissipation Relation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

5 Quantization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

5.1 Standard Hydrogen Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

5.2 Black Body Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

5.3 Photoelectric Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

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5.4 Compton Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

5.5 Specific Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

5.6 Spin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

6 Wave-like Nature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

6.1 Early light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

6.1.1 Young’s Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

6.1.2 On the French side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

6.1.3 Interacting Newton Bullets? . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

6.2 X-rays and Bragg Scattering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

6.3 Davisson–Germer Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

6.4 Wavy Electrons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

7 Finding Structure: Scattering and Fission . . . . . . . . . . . . . . . . . . . . . . . . . 85

7.1 Light Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

7.2 Particle Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

7.2.1 Geiger–Marsden–Rutherford Scattering . . . . . . . . . . . . . . . . . . 88

7.2.2 Standard Model Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . 93

7.3 Nuclear Chain Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

8 Light in the Universe and the Invariance of Proper Time . . . . . . . . . . . 97

8.1 Michelson–Morley Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

8.2 Special Relativity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

8.2.1 Popular Relativity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

8.2.2 Minkowski Spacetime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

8.2.3 Twin Paradox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

8.2.4 NonEuclidean Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

8.3 And More Generally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

9 Dynamical Activity of the Vacuum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

9.1 Beginnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

9.2 Lamb Shift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

9.2.1 Lamb–Retherford Experiment. . . . . . . . . . . . . . . . . . . . . . . . . . 112

9.2.2 Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

9.3 Fluctuation Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

9.4 Casimir Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

9.5 Frenesy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

10 Phase Transitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

10.1 The Dream of Anaximenes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

10.2 Percolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

10.3 Criticality and Universality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

10.4 Superconductivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

10.5 Superfluidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

10.6 Bose–Einstein Condensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

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11 Nonlocality: Spooky Action at a Distance . . . . . . . . . . . . . . . . . . . . . . . . . 135

11.1 About Alice, Living Far away from Bob . . . . . . . . . . . . . . . . . . . . . . . . 137

11.2 Einstein’s Boxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

11.3 Einstein–Podolsky–Rosen Argument . . . . . . . . . . . . . . . . . . . . . . . . . . 140

11.4 Bell’s Inequality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

11.5 Bell Test Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

12 Future Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

12.1 Around 2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

12.1.1 The Statistical Mechanics of Geometry . . . . . . . . . . . . . . . . . . 151

12.1.2 Relativity versus Quantum Mechanics . . . . . . . . . . . . . . . . . . . 152

12.1.3 Quantum Statistical Mechanics . . . . . . . . . . . . . . . . . . . . . . . . . 153

12.2 Into the next hundred years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

12.2.1 Computational and Neuro(nal) Physics . . . . . . . . . . . . . . . . . . 155

12.2.2 Physics of Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

12.2.3 Many-Body Nonequilibrium Physics . . . . . . . . . . . . . . . . . . . . 159

12.2.4 Climate and Planetary Sciences . . . . . . . . . . . . . . . . . . . . . . . . 160

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

O autorze

Christian Maes is a professor of mathematical  physics and natural philosophy at the KU Leuven, and his research interests lie in the area of nonequilibrium phenomena, stochastic geometry and dynamical systems, and in deriving emergent features of multicomponent models. As a leading expert, Maes has made significant contributions to the study of nonequilibrium statistical mechanics, particularly in the areas of fluctuation theorems, large deviations, response theory and nonequilibrium thermodynamics. His work has helped to deepen our understanding of the behavior of systems that are far from thermal equilibrium, such as those found in living cells, in driven plasma and chemical reactions, and in active matter.  He developed a strong interest in the analysis of experiments and their results as a teaching tool and as a catalyst for advancing our understanding.  

Christian Maes is on the editorial board of the Springer book series Fundamental Theories of Physics, and serves as associate editor of the Journal of Statistical Physics, and section editor for Statistical Physics of the Annales Henri Poincaré.

Blurb

The main aim of this book is to shine a spotlight on key experiments and their crucial importance for advancing our understanding of physics. Physics is an empirical science, and experiments have always been a driving force in the development of our understanding of nature.  Facts matter.  In that sense, the book attempts to be complementary to the many popularizations of theoretical physics, and to counterbalance the frequent emphasis there on more speculative ideas.

Experimental physics is also an essential pillar in physics teaching, as well as helping broader audiences to better understand important concepts, particularly in challenging fields such as relativity or quantum physics, where our common sense intuition often fails.

Readers are taken on an historical journey, starting with “Free Fall” and culminating in “Spooky Action at a Distance”. En route they will encounter many important branches of physics, whose main ideas and theoretical description will be given a more empirical meaning. At the end, the reader is invited to reflect on what could be exciting and important directions for fundamental physics. All readers with an undergraduate degree in physical sciences or engineering will enjoy and learn much from this stimulating and original text.