Sometimes late at night, I turn on a podcast and just lie in bed listening to it until I fall asleep. Perhaps the best podcast I’ve ever encountered is After On, hosted by Dan Reid because the host really takes the time to thoroughly familiarize himself with the research of whoever he’s interviewing.
On episode 8, which I highly recommend any science types listen to, Reid interviewed British astronomer Stephen Webb about the Fermi’s paradox, which is the mystery of why why we haven’t been visited by aliens yet, given that life on other planets is so probable.
Well, my first question has always been why does anyone think life is probable? Yes it emerged on Earth as soon as conditions were right, but it only emerged once. All life on earth, as far as we know, is descended from a single biogenesis so that right there tells me that life is not that probable, because if it were, then why on even this planet, perfectly suited to life, did it not occur at least twice? Maybe the original life had such a head-start that no new biogenesis could compete?
A popular estimate from the Drake equation is that there are 10,000 intelligent species just in our galaxy alone, with many having had far more time to evolve (both genetically and culturally) than we’ve had. So why haven’t they visited us? One theory is that once life gets intelligent enough to build technology, it destroys itself through nuclear war long before it figures out how to travel to distant planets.
Another theory is that intelligent life is out there watching us, but they want to give us a chance to develop on our own, without interference. While it seems plausible that one advanced species might take this ethical attitude, Webb finds it implausible that thousands of intelligent species would all agree.
However Reid mentions near the end of the show, that all the aliens wouldn’t need to agree, because the first (and thus most advanced) of the intelligent species would call the shots and make the rules. I was thinking the same thing during the interview. Many countries in the World don’t agree with the foreign policy of the United States, but all have to live with it because the U.S. (or those who lobby it) call the shots. so intragalactic politics might work the same way. Webb however thinks that the reason no one’s visited us is because we’re alone.
Existence of God?
The strangest part of the interview comes around the 1 hour and 7 minute mark when Webb starts talking about the universe having about a dozen parameters, each of which are precisely set to allow galaxies and stars to form and so the odds of the universe as we know it is only one in ten to the power of 229. Since such slim odds are unlikely to have occurred by chance, Webb argues that there might be a creator (not necessarily God per se, but a more advanced life form) who created or simulated our universe.
I’m no astronomy expert but this argument sounds fallacious. No matter what parameters the universe had, the odds of it having those precise parameters would be be extremely slim, so by Webb’s logic, anything that would have happened would be evidence for a creator. How do we know that something even more impressive than life (as we know it) would not have occurred with a different set of parameters?
An alternative possibility Webb argues is that there are 10 to the power of 500 universes, and by definition, we just found ourselves in that rare one that supports life.