More Science: The Universe Is Not Enough

Disclaimer: I recognize that there are important societal issues to consider when discussing overpopulation. This is a math/science post, so I'm planning to completely ignore those.

"Humans are overcrowding the planet!" is a concern that crops up at least once a generation. Up until now, I have had little patience with the doomsayers. The idea that a family's children after the first (or second or third) are a burden that the world cannot accept is disturbing and offensive to me. Yes, there ar...