# Infinite Derivative Gravity: A Ghost and Singularity-free Theory

@article{Conroy2017InfiniteDG, title={Infinite Derivative Gravity: A Ghost and Singularity-free Theory}, author={Aindri'u Conroy}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2017} }

The objective of this thesis is to present a viable extension of general relativity free from cosmological singularities. A viable cosmology, in this sense, is one that is free from ghosts, tachyons or exotic matter, while staying true to the theoretical foundations of General Relativity such as general covariance, as well as observed phenomenon such as the accelerated expansion of the universe and inflationary behaviour at later times. To this end, an infinite derivative extension of…

## 14 Citations

### Infinite Derivative Gravity: A finite number of predictions

- Physics
- 2019

Ghost-free Infinite Derivative Gravity (IDG) is a modifed gravity theory which can avoid the singularities predicted by General Relativity. This thesis examines the effect of IDG on four areas of…

### On aspects of infinite derivatives field theories & infinite derivative gravity

- Physics
- 2018

Infinite derivative theory of gravity is a modification to the general theory of relativity. Such modification maintains the massless graviton as the only true physical degree of freedom and avoids…

### Criteria for resolving the cosmological singularity in Infinite Derivative Gravity

- Physics
- 2016

Einstein's General theory of relativity permits space-time singularities, where null congruences \emph{focus} in the presence of matter, which satisfies an appropriate energy condition. In this…

### Revealing infinite derivative gravity’s true potential: The weak-field limit around de Sitter backgrounds

- Physics
- 2018

General Relativity is known to produce singularities in the potential generated by a point source. Our universe can be modelled as a de Sitter (dS) metric and we show that ghost-free Infinite…

### Conditions for defocusing around more general metrics in Infinite Derivative Gravity

- Mathematics, Physics
- 2018

Infinite Derivative Gravity is able to resolve the Big Bang curvature singularity present in general relativity by using a simplifying ansatz. We show that it can also avoid the Hawking- Penrose…

### Testing gravity in the local universe

- Geology
- 2018

General relativity (GR) has stood as the most accurate description of gravity for the last 100 years, weathering a barrage of rigorous tests. However, attempts to derive GR from a more fundamental…

### Gravitational radiation in infinite derivative gravity and connections to effective quantum gravity

- PhysicsPhysical Review D
- 2018

The Hulse-Taylor binary provides possibly the best test of GR to date. We find the modified quadrupole formula for infinite derivative gravity (IDG). We investigate the backreaction formula for…

### Pushing the limits of time beyond the Big Bang singularity: The branch cut universe

- MathematicsAstronomische Nachrichten
- 2021

In this article we follow a previously developed theoretical approach, based in the tools of the singular semi-Riemannian geometry, to push the limits of time beyond the primordial spacetime…

### Local and Nonlocal Thermal Field Theory

- Physics
- 2019

Firstly, nonlocal field theories will be motivated, primarily in the gravity sector. We discuss how nonlocal theories of gravity can circumvent typical problems of finitely-many higher derivative…

### Parity-violating gravity and GW170817 in non-Riemannian cosmology

- PhysicsJournal of Cosmology and Astroparticle Physics
- 2019

The cosmological propagation of tensor perturbations is studied in the context of parity-violating extensions of the symmetric teleparallel equivalent of General Relativity theory. This…

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