Locality in Gravity

The research presented in this dissertation is primarily focused around the study of locality in quantum gravity. The emergence of locality is intimately tied to many important questions in the field, including the emergence of the bulk in the Anti-de Sitter/Conformal Field Theory correspondence, and to holography in more general spacetimes, as well as the contradictions presented in the AMPS argument of the black hole information paradox. In particular, this thesis starts by studying the gauge redundancy related to the observer dependence in quantum gravity as well as its implications in the distribution of gravitational degrees of freedom. This picture is then applied to the black hole information paradox presenting a picture discussing deviations of local effective field theory around the horizon. Following the apparent fundamental role taken by the holographic entanglement proposal in AdS/CFT, I then present a generalization of this proposal to general spacetimes, proving that the appropriate a generalization satisfies the inequalities associated with von Neumann entropy. This picture is then used to study the Hilbert space structure of such theories. In chapter 4, I also present a model that suppressed isocurvature fluctuations present for interesting parameter ranges for axions in high scale inflation scenarios. Finally, the last chapter concludes with the reconstruction of bulk operators in AdS/CFT, where such a reconstruction has no prior knowledge of bulk geometry as a starting point. The result uses intimate connections to quantum error correction and obtains the bulk conformal metric as a byproduct of the construction