No, but I haven't read any science fiction since my teenage years. (Sadly, because I would like to... just don't have the time.) I actually don't remember read

No, but I haven't read any science fiction since my teenage years. (Sadly, because I would like to... just don't have the time.) I actually don't remember reading this anywhere, it just seemed an obvious idea. The idea that humanity would expand into a Type III civilization and near light speed is very old, probably dating to the work done by the British Interplanetary Society on interstellar travel. I don't have citations handy, but I remember reading a critique of generation ships which basically boiled down to "if you travel less than 0.9c, you can expect someone else to leave after you do but arrive sooner." Applying the same logic to other civilizations just seemed like common sense...