I suppose that my questions are pretty basic, but I've been trying to find out the answers and not succeeded. 1.- Do cosmologists really think that the vacuum state suddenly changed in the early Universe? If so, would it be like a phase transition? If so, first or second orther? 2.- Does the vacuum energy explain anything about the Universe expansion? 3.- Are there parts of the Universe that are not causally connected with ours? If so, did these other parts choose the same vacuum state as ours? After all, Higgs boson has been experimentally found and spontaneous symmetry breaking can't be be as artificial as it seems to be. I'm sorry for posting three questions at the same time but I don't really undestand if the Standard Model of particle physics plays any relevant role in Cosmology or not. If this is not the right place to make this questions could you, please, let me know where can I look for answers?