Life on Earth is premature: that is why we are alone in the cosmos

4 August 2016

Since the Fermi Paradox intrigues me. Life on Earth is premature. A fluke perhaps. The universe is still relatively young, that’s why we haven’t detected signs of intelligent life elsewhere.

If we compare the present age of the universe, against its projected lifespan, possibly twenty trillion years, then it has an age comparable to an eighteen day old child, who would be expected to live for seventy years. Eighteen days. That’s pretty young.

The cosmos isn’t yet mature enough to be teeming with life.

The dominant factor proved to be the lifetimes of stars. The higher a star’s mass, the shorter its lifetime. Stars larger than about three times the sun’s mass will expire before life has a chance to evolve. Conversely, the smallest stars weigh less than 10 percent as much as the Sun. They will glow for 10 trillion years, giving life ample time to emerge on any planets they host. As a result, the probability of life grows over time. In fact, chances of life are 1000 times higher in the distant future than now.

Originally published Thursday 4 August 2016, with subsequent revisions, updates to lapsed URLs, etc.