> the most plausible explanation for me is still that we happen to live in a historical dark zone.
I am no expert, but I remember reading somewhere that our Sun is among the first generation of solar systems that were born with enough heavy elements to make life based on carbon, oxygen, nitrogen, occasional iron etc. possible.
That there first needs to be some generations of starts going nova so that the stars have generated the heavier elements, and then the supernova explosions have to spread these around to that then the new interstellar clouds have enough of these element when they collapse to next generation stars and solar systems.
Another argument I heard, compatible with life being a fairly easy reaction;
A loglinear graph tracing the genetic complexity of life reaches zero about seven billion years. Obviously this implies an extraterrestrial origin of life theory. But it would also say life came into existence half-way into the big bang expansion and has been gaining complexity ever since. We are the result of this. But there's no reason to think there are other lifes that have that much of a head start. Thus it is not surprising that the manifestations of other intelligences haven't appeared.
It's a logarithmic graph. It doesn't go to zero. It just goes to 10^0 which is 1. And in this case one billion units of whatever. -1 is 100 million etc..
Yes and no. While our solar system is sufficiently metal rich, we're not especially early. There are systems of comparable generation that are younger than ours. This depends more on where you are in the galaxy than when you are.
I am no expert, but I remember reading somewhere that our Sun is among the first generation of solar systems that were born with enough heavy elements to make life based on carbon, oxygen, nitrogen, occasional iron etc. possible.
That there first needs to be some generations of starts going nova so that the stars have generated the heavier elements, and then the supernova explosions have to spread these around to that then the new interstellar clouds have enough of these element when they collapse to next generation stars and solar systems.