Notes on O’Neill’s Semi-Riemannian Geometry with ... O'Neill.pdf · Notes on O’Neill’s...
Transcript of Notes on O’Neill’s Semi-Riemannian Geometry with ... O'Neill.pdf · Notes on O’Neill’s...
Notes on O’Neill’sSemi-Riemannian Geometry with Applications to Relativity
Jason Payne
November 25, 2011
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 2
Contents
1 Manifold Theory 9Smooth Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Smooth Mappings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Tangent Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Differential Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Vector Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9One-Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Submanifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Immersions and Submersions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Topology of Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Some Special Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Integral Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 Tensors 11Basic Algebra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Tensor Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Interpretations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Tensors at a Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Tensor Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Contraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Covariant Tensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Tensor Derivatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Symmetric Bilinear Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Scalar Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3 Semi-Riemannian Manifolds 13Isometries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13The Levi-Civita Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Parallel Translation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Geodesics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13The Exponential Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Curvature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Sectional Curvature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Semi-Riemannian Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Type-Changing and Metric Contraction . . . . . . . . . . . . . . . . . . . . . . . . 13Frame Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Some Differential Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Ricci and Scalar Curvature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Semi-Riemannian Product Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . 13Local Isometries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Levels of Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4 Semi-Riemannian Submanifolds 15Tangents and Normals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15The Induced Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Geodesics in Submanifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Totally Geodesic Submanifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Semi-Riemannian Hypersurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Hyperquadratics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15The Codazzi Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Totally Umbilic Hypersurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15The Normal Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15A Congruence Theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Isometric Immersions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Two-Parameter Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5 Riemannian and Lorentz Geometry 17The Gauss Lemma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Convex Open Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Arc Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Riemannian Distance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Riemannian Completeness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Lorentz Casual Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Timecones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Local Lorentz Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Geodesics in Hyperquadratics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Geodesics in Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Completeness and Extendability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6 Special Relativity 19Newtonian Space and Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Newtonian Space-Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Minkowski Spacetime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Minkowski Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Jason Payne 4
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Particles Observed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Some Relativistic Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Lorentz-Fitzgerald Contraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Energy-Momentum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19An Accelerating Observer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7 Constructions 21Deck Transformations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Orbit Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Orientability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Semi-Riemannian Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Lorentz Time-Orientability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Volume Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Vector Bundles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Local Isometries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Matched Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Warped Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Warped Product Geodesics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Curvature of Warped Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Semi-Riemannian Submersions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
8 Symmetry and Constant Curvature 23Jacobi Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Tidal Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Locally Symmetric Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Isometries of Normal Neighborhoods . . . . . . . . . . . . . . . . . . . . . . . . . 23Symmetric Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Simply Connected Space Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Transvections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
9 Isometries 25Semiorthogonal Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Some Isometry Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Time-Orientability and Space-Orientability . . . . . . . . . . . . . . . . . . . . . . 25Linear Algebra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Space Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Killing Vector Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25The Lie Algebra i(M) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25I(M) as Lie Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Homogeneous Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Jason Payne 5
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
10 Calculus of Variations 27First Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Second Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27The Index Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Conjugate Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Local Minima and Maxima . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Some Global Consequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27The Endmanifold Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Focal Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Variation of E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Focal Points Along Null Geodesics . . . . . . . . . . . . . . . . . . . . . . . . . . . 27A Causality Theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
11 Homogeneous and Symmetric Spaces 29More about Lie Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Bi-Invariant Metrics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Coset Manifolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Reductive Homogeneous Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Symmetric Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Riemannian Symmetric Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Duality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Some Complex Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
12 General Relativity; Cosmology 31Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31The Einstein Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Perfect Fluids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Robertson-Walker Spacetimes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31The Robertson-Walker Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Robertson-Walker Cosmology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Friedmann Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Geodesics and Redshift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Observer Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Static Spacetimes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
13 Schwarzschild Geometry 33Building the Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Geometry of N and B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Schwarzschild Observers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Schwarzschild Geodesics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Free Fall Orbits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Perihelion Advance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Jason Payne 6
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Lightlike Orbits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Stellar Collapse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33The Kruskal Plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Kruskal Spacetime . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Black Holes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Kruskal Geodesics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
14 Causality in Lorentz Manifolds 35Causality Relations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Quasi-Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Causality Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Time Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Achronal Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Cauchy Hypersurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Warped Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Cauchy Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Spacelike Hypersurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Cauchy Horizons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Hawking’s Singularity Theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Penrose’s Singularity Theorem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Jason Payne 7
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 8
Chapter 1
Manifold Theory
Smooth Manifolds
Smooth Mappings
Tangent Vectors
Differential Maps
Curves
Vector Fields
One-Forms
Submanifolds
Immersions and Submersions
Topology of Manifolds
Some Special Manifolds
Integral Curves
9
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 10
Chapter 2
Tensors
Basic Algebra
Tensor Fields
Interpretations
Tensors at a Point
Tensor Components
Contraction
Covariant Tensors
Tensor Derivatives
Symmetric Bilinear Forms
Scalar Products
11
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 12
Chapter 3
Semi-Riemannian Manifolds
Isometries
The Levi-Civita Connection
Parallel Translation
Geodesics
The Exponential Map
Curvature
Sectional Curvature
Semi-Riemannian Surfaces
Type-Changing and Metric Contraction
Frame Fields
Some Differential Operators
Ricci and Scalar Curvature
Semi-Riemannian Product Manifolds
Local Isometries
Levels of Structure
13
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 14
Chapter 4
Semi-Riemannian Submanifolds
Tangents and Normals
The Induced Connection
Geodesics in Submanifolds
Totally Geodesic Submanifolds
Semi-Riemannian Hypersurfaces
Hyperquadratics
The Codazzi Equation
Totally Umbilic Hypersurfaces
The Normal Connection
A Congruence Theorem
Isometric Immersions
Two-Parameter Maps
15
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 16
Chapter 5
Riemannian and Lorentz Geometry
The Gauss Lemma
Convex Open Sets
Arc Length
Riemannian Distance
Riemannian Completeness
Lorentz Casual Character
Timecones
Local Lorentz Geometry
Geodesics in Hyperquadratics
Geodesics in Surfaces
Completeness and Extendability
17
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 18
Chapter 6
Special Relativity
Newtonian Space and Time
Newtonian Space-Time
Minkowski Spacetime
Minkowski Geometry
Particles Observed
Some Relativistic Effects
Lorentz-Fitzgerald Contraction
Energy-Momentum
Collisions
An Accelerating Observer
19
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 20
Chapter 7
Constructions
Deck Transformations
Orbit Manifolds
Orientability
Semi-Riemannian Coverings
Lorentz Time-Orientability
Volume Elements
Vector Bundles
Local Isometries
Matched Coverings
Warped Products
Warped Product Geodesics
Curvature of Warped Products
Semi-Riemannian Submersions
21
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 22
Chapter 8
Symmetry and Constant Curvature
Jacobi Fields
Tidal Forces
Locally Symmetric Manifolds
Isometries of Normal Neighborhoods
Symmetric Spaces
Simply Connected Space Forms
Transvections
23
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 24
Chapter 9
Isometries
Semiorthogonal Groups
Some Isometry Groups
Time-Orientability and Space-Orientability
Linear Algebra
Space Forms
Killing Vector Fields
The Lie Algebra i(M)
I(M) as Lie Group
Homogeneous Spaces
25
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 26
Chapter 10
Calculus of Variations
First Variation
Second Variation
The Index Form
Conjugate Points
Local Minima and Maxima
Some Global Consequences
The Endmanifold Case
Focal Points
Applications
Variation of E
Focal Points Along Null Geodesics
A Causality Theorem
27
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 28
Chapter 11
Homogeneous and Symmetric Spaces
More about Lie Groups
Bi-Invariant Metrics
Coset Manifolds
Reductive Homogeneous Spaces
Symmetric Spaces
Riemannian Symmetric Spaces
Duality
Some Complex Geometry
29
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 30
Chapter 12
General Relativity; Cosmology
Foundations
The Einstein Equations
Perfect Fluids
Robertson-Walker Spacetimes
The Robertson-Walker Flow
Robertson-Walker Cosmology
Friedmann Models
Geodesics and Redshift
Observer Fields
Static Spacetimes
31
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 32
Chapter 13
Schwarzschild Geometry
Building the Model
Geometry of N and B
Schwarzschild Observers
Schwarzschild Geodesics
Free Fall Orbits
Perihelion Advance
Lightlike Orbits
Stellar Collapse
The Kruskal Plane
Kruskal Spacetime
Black Holes
Kruskal Geodesics
33
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 34
Chapter 14
Causality in Lorentz Manifolds
Causality Relations
Quasi-Limits
Causality Conditions
Time Separation
Achronal Sets
Cauchy Hypersurfaces
Warped Products
Cauchy Developments
Spacelike Hypersurfaces
Cauchy Horizons
Hawking’s Singularity Theorem
Penrose’s Singularity Theorem
35
Notes on O’Neill’s Semi-Riemannian Geometry with Applications to Relativity
Jason Payne 36
Bibliography
[1] B. O’Neill. Semi-Riemannian Geometry with Applications to Relativity. Academic Press,1983.
37