I've looked through the force chapter a few times and also the spending xp chapters. I'm wondering though: Does one need time or a mentor to train new force powers? (thus for move-basic if he didn't have learnt it so far). Or can the characters just learn it without having to have an explanation there? (ingame and also mechanicswise)

Do you need time or a mentor to train new force powers, or can a character just learn it without needing an in-game justification? (Thus for move-basic if you haven't learned it yet.)