how about trying some nice science fiction
theres Ender's game by Orson Scott Card
that books awesome, basically he answers the question on how war in space will be fought, and exstremely bright children are sent into space at a young age [ like 6] to learn how to fight, and how to be leaders. quite good
theres also
The Forever War ill edit post later when i find my copy and who its by
this basically addresses the question abotu relativity, a way to travel very fast to other solar systems is discovered, but while your war ship may age only a few months, by the time u get back home Earth will have aged like 100 yrs. a war occurs with an alien race and u can never be sure if ure fighting less advanced aliens [ i.e they left their home planet relatively before you] or more advanced so you could be fighting against technology like 100yrs into your future rather interesting read, only problem is when its set, as the book was written in like the 70's, space trave and the war begins in something like 1996 lol