Cosmic Plasma (Book) | Plasma-Universe.com

By Hannes Alfvén

Publ. 1981. Astrophysics and Space Science Library, Vol. 82 (1981) Springer Verlag. ISBN 90-277-1151-8. Buy

Extract:

The aims of the present monograph may be summarized as follows:

(1) Attention will be given to the question of how much knowledge can be gained by a systematic comparison of different regions of plasma. We will consider plasmas with linear dimensions which vary from laboratory size up to the Hubble distance.
(2) The traditional magnetic field description of plasmas will be supplemented by an electric current description. It is demonstrated that many problems are easier to understand with a dualistic approach.
(3) A rather strict distinction will be made between plasma regions which are accessible to in situ diagnostics and those regions which are not. In the former, we can expect to understand the plasma phenomena reasonably well, and to be able to discriminate between different interpretations, whereas in the latter regions, conclusions must necessarily remain largely speculative.
(4) It is claimed in this monograph that in the speculative domain, those theories, which are based on what we know from laboratory experiments and from regions accessible to spacecraft measurements, deserve higher credibility than those which are based on theories which we know to be misleading when applied to regions that have been subject to high-quality diagnostics.

As it is impossible to treat an extensive and complicated field like cosmic plasma physics in a rigorous way in a monograph of the present size, we have followed the policy that – as Kadomtsev (1965) puts it – “when rigour appears to conflict with simplicity, simplicity is given preference”.

PREFACE

CHAPTER I / SURVEY

I.1. Experimental and Theoretical Approach to Plasma Physics
I.2. Plasma Phenomena in Laboratory and Space

I.2.1. Scaling Procedures
I.2.2. Simulation Experiments
I.2.3. Comparison Between Laboratory and Space Investigations

I.3. Field and Particle Aspects of Plasmas
I.4. Present State of the Classical Theory
I.5. Boundary Conditions. Circuit Dependence
I.6. Cosmology and the Origin of the Solar System
1.7. Aims of the Monograph

CHAPTER II / ELECTRIC CURRENTS IN SPACE PLASMAS 11

II.1. Dualism in Physics 11
II.2. Particle-Related Phenomena in Plasma Physics 12
II.3. Magnetic Field Lines 12

II.3.1. Magnetic Field and Electric Current Description of the Magnetosphere 13
II.3.2. Particle Motion in the Magnetosphere 15
II.3.3. Conclusions About `Field Line Reconnection’ and ‘Merging’ in the Stationary Magnetosphere 16

1I.4. Filaments 16

II.4.1. Observations of Filaments 16
II.4.2. Constriction of a Discharge 21
II.4.3. Pinch Effect. The Bennett Relation 22
II.4.4. Filamentary Currents in Force-Free Magnetic Fields 23
II.4.5. Theory of Magnetic Ropes 25
II.4.6. Ion Pumps 26
II.4.7. Flux Ropes in the Ionosphere of Venus 26

II.5. Local Plasma Properties and the Circuit 26

II.5.1. Boundary Conditions 28
II.5.2. ‘Invisible’ Transfer of Energy 28
II.5.3. ‘Magnetic Merging’ Theories 29

II.6. Electric Double Layers 29

II.6.1. General Properties of Double Layers 29
II.6.2. Double Layers in the Magnetosphere 32
II.6.3. Energy Release in Double Layers 33
II.6.4. Exploding Double Layers 33
II.6.5. A Circuit with a Double Layer 34

II.7. Field-Aligned Currents as `Cables’ 36
II.8. An Expanding Circuit 37
II.9. Different Types of Plasma Regions 37

II.9.1. ‘Passive’ Plasma Regions
II.9.2. ‘Active’ Plasma Regions 37
II.9.3. Plasma Cables 37
II.9.4. Ionospheric Projection of Active and Passive Plasma Regions 38
II.9.5. Boundary Current Sheets 39

II.10. Cellular Structure of Space 40
II.11. Fine Structure of Active Plasma Regions 40

CHAPTER III / CIRCUITS 42

III.1. Importance of Electric Current Models 42

III.1.1. Particle Description 42
III.1.2. Different Types of Electric Currents 43
III.1.3. Transfer of Energy Between a Circuit and a Moving Plasma 44

III.2. The Auroral Circuits 48
III.3. Rotating Magnetized Body Surrounded by a Plasma 51
III.4. The Heliospheric Current System 53

III.4.1. The .Sector Structure’ and the Equatorial Current Layer 53
III.4.2. Construction of the Heliospheric Current Model 54
III.4.3. Properties of the Heliospheric Circuit 56
III.4.4. Extrapolation to Galactic Dimensions: Double Radio Sources 56

III.5. Circuits of Magnetospheric Tail, Comets, and Venus 59

III.5.1. Tail Circuit and Magnetic Substorms 59
III.5.2. Current System in Comets 60
III.5.3. Current System in the Magnetosphere of Venus 60
III.6. Magnetospheric Circuit 62
III.6.1. Zero Order Approximation : One-Particle Problem 62
III.6.2. First Order Approximation : Plasma Flux Small 62
1II.6.3. The Three First-Approximation Circuits 65
III.6.4. Phenomena Produced by First Approximation Currents 67
III.6.5. Second Order Approximation. Realistic Plasma Flow 68
III.6.6. Magnetic Field Changes 68
III.6.7. Front (Shock Front) Circuit 68
III.6.8. Magnetopause Circuit 69
III.6.9. Solar Wind — Auroral Circuit 69
III.6.10. The Tail Circuit 70
III.6.11. Third Approximation and Comparison with Observation 70
III.6.12. The Three-Ring Model 71

III.7. Other Magnetospheres 73
III.8. Solar Prominence Circuit and Solar Flares 73
III.9. Solar Wind Acceleration 74
III.10. Transfer of Energy from the Solar Core to the Aurora 77

CHAPTER IV / THEORY OF COSMIC PLASMAS 78

IV.1. Classical Theory and Its Difficulties 78

IV.1.1. The Reverse Deflection 79

IV.2. Ionization 79

IV.2.1. Ionization by Light, by Particle Radiation, and by Electric Currents 79
IV.2.2. Transition Between a Plasma and a Neutral Gas 82

IV.3. Cosmic Abundances and Differentiation 82

IV.3.1. Cosmic Abundances 82
IV.3.2. Observations of Chemical Differentiation 83
IV.3 3. Separation Due to Different Ionization Potentials 84
IV.3.4. Separation Due to Mass Differences 84
IV.3.5. Separation Due to Different Vapor Pressures 84

IV.4. Turbulence 84
IV.5. Flux Amplification 86

IV.5.1. Production of Cosmic Magnetic Fields 86
IV.5.2. Self-Exciting Dynamos 87
IV.5.3. Theories of Self-Exciting Dynamos 87
IV.5.4. A Flux Amplification Mechanism 88
IV.5.5. Production of Cosmic Magnetic Fields by the Kink Instability 89

IV.6. Critical Velocity 91

IV.6.1. Prediction of the Critical Velocity in the Early Solar System 91
IV.6.2. Experimental Discovery 91
IV.6.3. Theory 92
IV.6.4. The Critical Velocity and Space Research 92

IV.7. Dusty Plasma 92

IV.7.1. Solid Particles as Part of a Plasma 93
IV.7.2. Electromagnetically and Gravitationally Controlled Motion of Solid Particles 93

IV.8. Formation and Evolution of Interstellar Clouds 93

IV.8.1. Three Special Cases 95
IV.8.2. Force-Free Magnetic Fields and the Production of Filaments 96
IV.8.3. Do Magnetic Fields Aid or Counteract a Compression? 96
IV.8.4. Pinch Compression of Dark Interstellar Clouds 97

IV.9. Ambiplasma 98

IV.9.1. Properties of an Ambiplasma 98
IV.9.2. The Annihilation Reactions 98
IV.9.3. Radiations from an Ambiplasma 100
IV.9.4. Main Ambiplasma Problems 102
IV.9.5. Separation of Matter and Antimatter 102
IV.9.6. On the Co-Existence of Matter and Antimatter 104

IV.10. High Energy Phenomena 104

IV.10.1. Sources of Energy and Acceleration Processes 105

IV.10.1.1. Varying Magnetic Fields 105
IV.10.1.2. Acceleration in Double Layers 105
IV.10.1.3. Annihilation 106
IV.10.1.4. Gravitation 106

IV.10.2. Magnetic Pumping 107
IV.10.3. Regions of Cosmic Ray Acceleration 108

IV.10.3.1. Heliospheric and Galactic Cosmic Radiation 108
IV.10.3.2. Origin of Galactic Cosmic Rays 109

CHAPTER V / ORIGIN OF THE SOLAR SYSTEM

V.1. How We Can Reconstruct Earlier Epochs 110
V.2. Sources of Information 110
V.3. Impact of Magnetospheric Results III

V.3.1. Active and Passive Plasma Regions III
V.3.2. Externally Driven Currents III

V.4. Electromagnetic Effects Aiding the Formation and Contraction of Clouds 113
V.5. Chemical Differentation in the Primeval Cloud 113
V.6. Intrinsically Produced Currents 114
V.7. Band Structure and the Critical Velocity 115
V.8. Solar System in Formation 118

V.8.1. Interstellar Clouds 118
V.8.2. Formation of Protostars 119
V.8.3. Planet-Satellite Formation 120
V.8.4. Observation of Solar Systems in Formation 121

V.9. Hetegony and the `Hetegonic Principle’ 122

CHAPTER VI / COSMOLOGY 123

VI.l. The State of Cosmology 123

VI.1.1. Historical Survey 123
VI.1.2. The Big Bang Hypothesis 125

VI.13. Homogeneous and Inhomogeneous Models 126

VI.l.3.1. Cellular Structure of Space 126
VI.1.3.2. Mass Distribution in the Universe 126
VI.1.3.3. Mass of the Metagalaxy and the Schwarzschild Limit 128

VI.1.4. The Hubble Expansion 129

VI.1.4.1. The Hubble Parameter 129
VI.1.4.2. Euclidean Model of the Evolution of the Metagalaxy 131

VI.2. Coexistence of Matter and Antimatter 131

VI.2.1. Matter-Antimatter Symmetry 131
VI.2.2. Matter and Antimatter Cells 132
VI.2.3. Size of Cells : Galactic or Smaller? 133
VI.2.4. Structure of a Symmetric Galaxy 134

VI.2.4.1. Solar System 134
VI.2.4.2. Cometary Reservoir 135

VI.2.5. Objections to the Existence of Antimatter 136
VI.3. Annihilation as a Source of Energy 137
VI.3.1. Argument for the Existence of Antimatter 137
VI.3.2. Similarity of Electromagnetic Radiation from the Two Kinds of Matter 138
VI.3 3. Radiation from Annihilation Processes 138
VI.3.4. Leidenfrost Layers and Annihilation at the Cell Walls 138
VI.3.5. Annihilation in Cosmic Clouds 139
VI.3.6. Bodies Falling into a Star of Opposite Kind of Matter 139
VI.3.7. Model of an Ambistar 141

VI.3.7.1. Ambistar Model I 141
VI.3.7.2. Stellar Collisions 143
VI.3.7.3. Ambistar Model II 143
VI.3.7.4. Observable Properties of an Ambistar 144
VI.3.7.5. Blueshifts 144
VI.3.7.6. QSO Scenario 144
VI.3.7.7. Continuous X-Ray Background Radiation 146

VI.4. Hubble Expansion in a Euclidean Space 146

VI.4.1. Non-Cosmological Redshifts of Some QSOs 146
VI.4.2. Consequences of Non-Cosmological Interpretation of QSO Redshifts 147

VI.5. A Model for the Evolution of the Metagalaxy 148.

VI.5.1. The Proto-Metagalaxy 148
VI.5.2. The Kinetic Energy of the Hubble Expansion 149
VI.5.3. Formation of the Proto-Metagalaxy 149
VI.5.4. Other Cosmological Problems 150

VI.6. Other Metagalaxies 151
VI.7. Discussion 151
VI.8. Conclusions 152

REFERENCES 153
INDEX

Reviews

Kulsrud, R. M. “Cosmic Plasma“, 1983, Physics Today 36, 56

Contents

Reviews