Izaurieta Aranda, FernandoMohan Chougule, Sumeet2023-01-062024-05-152024-08-282023-01-062024-05-152024-08-282022https://repositorio.udec.cl/handle/11594/10514Thesis for the academic degree of Doctor in Physical Sciences.The study of black holes is a fascinating and active area of research in theoretical physics. In recent years, the development of effective field theory (EFT) has provided a robust framework for studying the properties and behavior of black holes. In this thesis, we apply the principles of EFT to study black holes and Q-balls. Using the EFT for the black holes in 3+1 D, we will look at the hairy black hole background to study its fluctuations in a model-independent way and analyze the quasinormal modes of the hairy black holes. This allowed us to show the possible gravitational wave signatures of hairy black holes. Skyrme model is an EFT of QCD which describes mesons, and we will focus on the pions with vanishing topological/Barynoic charge. This opens the door for studying non-topological solitonic configurations, which are Q-balls. We also research the mini-superspace of the 2+1 D pure gravity, which lets us explore the Lorentzian path integral and the Euclidean geometries’ partition function. We obtain the logarithmic correction to the BTZ black hole entropy naked singularities without using CFT. Using the Euclidean partition function, we also calculate the logarithmic corrections to the entropy of the finite temperature BIon solution.spaCreative Commoms CC BY NC ND 4.0 internacional (Atribución-NoComercial-SinDerivadas 4.0 Internacional)Codelo SkyrmeTermodinámicaHoyos Negros (Astronomía)Theoretical Models of Black Holes and some implications for Q-balls.Tesis