Gravitational Theories Beyond General Relativity (eBook)

Supervisor’s Foreword 6
Abstract 8
Acknowledgements 9
Contents 10
1 Introduction 12
1.1 Prelude 12
1.2 General Relativity 14
1.2.1 Cosmology 16
1.2.2 Gravitational Waves 17
1.3 Modified Gravity 20
1.3.1 Inflation 23
1.3.2 Quantum Gravity 27
1.4 Outline of This Thesis 29
References 31
2 Equivalence Between Dark Matter and Modified Gravity 33
2.1 Introduction 33
2.2 Classification of Extended Theories of Gravity 35
2.3 Application to Dark Matter 41
2.4 Conclusions 42
References 43
3 Gravitational Waves in Quantum Gravity 45
3.1 Introduction 45
3.2 Resummed Graviton Propagator and Gravitational Waves 46
3.3 Conclusions 50
References 50
4 Backreaction of Quantum Gravitational Modes 52
4.1 Introduction 52
4.2 Effective Quantum Gravity 54
4.3 Gravitational Wave Backreaction 55
4.4 Gravitational Wave Propagation 61
4.5 Conclusions 63
References 63
5 Higgs-Starobinsky Inflation 65
5.1 Introduction 65
5.2 Effective Field Theory of Gravity 66
5.3 Inflation in Quantum Gravity 66
5.4 Higgs-Starobinsky Inflation 68
5.5 Stability Under Radiative Corrections 69
5.6 Conclusions 71
References 71
6 Vacuum Stability During Inflation 73
6.1 Introduction 73
6.2 Non-minimal Couplings and the Mixing of Degrees of Freedom 75
6.3 Vacuum Stability in an Inflationary Universe 77
6.4 Conclusions 82
References 82
7 Conclusions 84
Reference 86
A Perturbative Unitarity 87
Reference 88