Into the darkness : forging a stable path through the gravitational landscape

Papadomanolakis, G. (2019)

Doctoral Thesis

In this thesis we study the landscape of gravitational models which modify GR by introducing an additional scalar degree of freedom (d.o.f.) to source Cosmic Acceleration. In particular we answer the question
"What is the complete set of theoretical conditions a gravitational model must satisfy, in order to give a theoretically viable cosmology?". In order to study the theoretical stability of extended models of gravity we emplout the E ective Field Theory of Dark Energy and Modied Gravity (EFToDE/MG). This is a unifying framework which allows us to study the landscape of gravitational models in a broad and model independent way. This will allow us to answer the research question in a model independent way.

• Modified gravity
• Cosmic acceleration
• Effective field theory
• Theoretical stability

• All authors: Papadomanolakis, G.
• Supervisor: Achúcarro, A.
• Co-supervisor: Silvestri, A.
• Committee: Roest, D.; Watson, G.S.; Eliel, E.R.; Holten, J.W. van
• Qualification: Doctor (dr.)
• Awarding Institution: Lorentz Institute, Faculty of Science, Leiden University
• Date: 2019-09-19
• Title of host publication: Casimir PhD Series
• ISBN (print): 9789085934127
• Name: 2019-28
• Sponsorship: The D-ITP consortium, an initiative by the NWO