Physics beyond the Standard Model (BSM) can be described in a consistent and general way through an Effective Field Theory (EFT). Ultimately, the goal is to associate eventual deviations of the SM with a particular BSM model. In this talk, I discuss the quality of that association, taking the 2 Higgs Doublet Model (2HDM) as BSM model. More specifically, I consider two EFT approaches to it: the Standard Model EFT (SMEFT) and the Higgs EFT (HEFT). In the former, I compare not only different truncations in the EFT expansion (dimension 6 vs. dimension 8), but I also ascertain the importance of loop matching. As for the HEFT, I question the assumption according to which the matching is unique. I present three HEFT matchings to the 2HDM, and show that different ones should be used according to the process and the region of parameter space.
With support from FCT through project UIDB/00777/2020
