First part of movie is solid, dramatic picture of mankind's hopeless state. It even felt like I was watching 'art-house' level film. But then pops out this completely funny change-past-from-future theory. So these are us, who are correcting the past from the future, using multi-dimensional space in black hole, created by the more distant future us?! And if future us will achieve such immense creative possibilities, why change the past?! Or, if the past has to change, how do future us suddenly become so powerless to not do it themselves?