Lorenzo Annulli just defended his PhD thesis on "Challenging theories of gravitation: dark matter, compact objects and gravitational waves", supervised by Vitor Cardoso and Leonardo Gualtieri. The thesis studied compact objects and new fundamental fields. One of the landmark calculations is the dynamical friction acting on bodies moving on scalar environments, or the energy loss by compact binaries evolving within scalar structures. The PhD jury was composed of Diego Blas, José Lemos, Ilidio Lopes and Thomas Sotiriou. The theory was awarded a "Distinction". Lorenzo is now moving to Aveiro, to the group of Prof. Carlos Herdeiro. Congratulations Lorenzo!