If you are a fan of hard science fiction(meaning no frankenstein monsters or other types os pseudo-science-fantasy), this book will blow your mind. the main premise is based on manipulating certain parameters of a system, changing one or two of them with purpose, and the other aspects have to change also. Just like with basic electricity. Change the voltage, and the amperage changes. Deal with the character development in the beginning ( yeah, junior, learn some patience..) especially with the recent NASA studies on preparing us for Mars colonies…What happened to almost every major “colony” on Earth that was started by a major power ? For me personally, Thank you Greg Bear!