The holographic correspondence:Probing bulk gravitational physics with Wilson lines and geodesic Witten diagrams

This thesis focuses on aspects of the holographic correspondence which are directly relevant to problems in quantum and classical gravity. Specifically, we use geodesic Witten diagrams, and gravitational Wilson lines in AdS/CFT to explore bulk gravitational physics. In Chapter 1, we start with a pedagogical review of the holographic correspondence, while in the rest of the chapters give a more technical exposition of the main results. In Chapter 2, we find a systematic way to evaluate geodesic Witten diagrams for external fields of arbitrary spin, and we decomposed the original Witten diagrams conformal blocks. In Chapter 3 and 4, we focus on gravity in three dimensions and exploit gravitational Wilson lines in AdS3/ CFT2. We use them to give a prescription to construct local bulk fields in global AdS3, and BTZ black hole geometries. Moreover, we use them to explicitly provide a notion of causality in higher spin gravity, which allows us to associate a Penrose diagram to higher spin black holes