Jacques Vanier is retired from the National Research Council of Canada and as adjunct professor in the Physics Department at the University of Montreal, Canada. He is a fellow of the Royal Society of Canada, the American Physical Society, and the Institute of Electrical and Electronic Engineers. He has written more than 120 journal articles and proceedings papers and is the author of several books on masers, lasers, and atomic clocks, addressing the physics involved in the functioning of that type of instrumentation. His main research work is oriented toward the understanding and physical application of quantum electronics phenomena.

• Preface vii Chapter 1 Introduction 1 Chapter 2 The Universe 4 2.1 A Short Trip Through the Universe 5 2.2 Physical Interactions Within the Universe 12 2.2.1 Gravitational Interaction 12 2.2.2 Electromagnetic Interaction 12 2.2.3 Strong Nuclear Interaction 13 2.2.4 Weak Nuclear Interaction 13 2.3 Physics Behind All That 13 2.3.1 Reality of the World 14 2.3.2 Our Tools 16 2.3.3 Our Goal 18 2.3.4 Minimum Energy and the Concept of Equilibrium 29 2.3.5 Conservation of Energy 30 2.3.6 An Astonishing General Principle; the Least Action Principle 33 2.3.7 Mechanical Energy 44 2.3.8 Internal Energy 44 2.3.9 Heat 45 2.3.10 Some Other Forms of Energy 46 2.3.11 Some Other Conservation Laws 47 2.3.12 Limits in Energy Exchanges: The Concept of Entropy 48 Chapter 3 Human Species 100 3.1 Our Body 101 3.1.1 Living Cells 103 3.1.2 Dynamics and Functions of Cells 115 3.1.3 Homo sapiens Brain and Mental Activities 128 3.2 Life, Origin, and Evolution 150 3.2.1 A Resume of the History of the Universe 150 3.2.2 On the Origin of Life 152 3.2.3 Speculations 159 3.2.4 Evolution 162 3.2.5 Darwinism 164 3.2.6 Subsequent Developments 168 3.2.7 Alternative Approaches 171 3.3 Homo sapiens 172 Chapter 4 Realism and Physicalism 178 4.1 Some Preliminary Remarks 178 4.1.1 Does Physics Deal with Reality? 178 4.2 Physics and Meta-Worlds 182Chapter 5 Conclusion 186 5.1 Our World 186 5.2 Matter, Space, Time 186 5.3 Mathematics 188 5.4 Basic Principle: Principle of Least Action, Lagrangians 189 5.5 An Overview 192 5.6 The Fundamental Questions 193 5.7 Life 194 5.8 The Mind 195 5.9 Language 195 5.10 Society and Culture 196 5.11 Myths 196 5.12 Homo sapiens Successes and Failures 197 5.12.1 Successes 197 5.13 Our Future 200 5.13.1 What Is That Universe? 203 5.13.2 What Are We? 204 5.13.3 Who Are We? 204 Bibliography .................................................................................................................................207Annexes .........................................................................................................................................209Annex A Elements of Mathematics; A Short and Easy Course in Mathematics, for the Newcomer in the Field. ................................................................................. 211Annex B The International System of Units (SI): New 2019 Version...................................226Annex C Relativity, Time, and Space ......................................................................................230Annex D Quantum Physics ...................................................................................................... 241Annex E Lagrangians ...............................................................................................................248Annex F Cosmology .................................................................................................................. 253Annex G Gravity, Relativity, and Black Holes ....................................................................... 262Annex H MRI and PET: Physics in help to Medicine ........................................................... 273Annex I Our Senses: Elementary Physics About Two of Them .......................................... 276Index ..............................................................................................................................................287