surprisingly interesting despite previous criticisms I avoided this movie at the cinemas because of general poor reviews online, and in the papers - however I thought the premise of the movie was interesting, and after a couple of years I decided to check it out for myself. Reviewers on this site have given it 1 - 10/10.
I found it interesting as a movie, with likable characters, including Paul Walkers portrayal of Chris, Marek, the physicist, and the corporation bad guys with/without a conscience. The movie moved along quickly, cutting from past to present just at the correct moments to heighten the drama. The production quality was good. Time travel/worm hole science is left for scientists to understand, and an explanation is not attempted in the movie, for which I am glad.
I don't know why some of the main characters were changed from the book, however the adaptation of a book to movie has to be a difficult thing, and if you take this movie at face value it's pretty entertaining.