It's probably manipulating this world to make it as perfectly incompatible with all the other worlds. Though those witches got a broom to fly, or something, so if they can manipulate this world, gosh darn it, I should be able to. Don't suppose you know anything about receivers and radio-waves, do you?
Yes, far less violationy of the laws of physics if it's just using matter from here. And thoughts and memories aren't exactly matter.