This is way above my head to answer your question coherently. One way to look at it is, that the possibility of colonizing the solar system is low, maybe impossible. Without this, at some point all energy will simply evaporate into all directions if we can't reach other suns. The Great Filter is an interesting study in this regard: http://en.wikipedia.org/wiki/Great_Filter

Besides, I found another interesting article regarding earths future: http://en.wikipedia.org/wiki/Future_of_the_Earth