Predicting the end of the world is a gruesome and somewhat inexact process, but statisticians have been working on this question for years. The estimates until now have been less than encouraging, but a new analysis from physicist Austin Gerig and his colleagues at the University of Oxford gives us reason to hope.
The Doomsday Argument is an idea that holds you can predict the number of humans that will ever exist by the number that have existed thus far. This traditional analysis of humanity’s future works with the assertion that about 70 billion humans have lived on Earth. Probability suggest there is a 95% chance we are among the last 95% of humans that will ever exist. Doing the math, that means 1.4 trillion humans are likely to be born before we go extinct.
So where would that 1.4 trillion figure leave civilization? If we assume the world population tops out at 10 billion, and we have 80-year life spans, Homo sapiens have 10,000 more years. That might sound like a lot, but it’s an evolutionary blink of the eye. The Gerig analysis attempts to estimate the real danger of various existential threats like nuclear war, disease, and cosmic disasters.
This new paper is based on the position that long-lived civilizations are rare in the universe. If they weren’t, we would probably be living in one. Since we don’t see very old alien civilizations everywhere, the likelihood of survival must be low. Gerig’s approach is mostly dense statistical analysis, but the bottom line is that humanity has a better chance of survival than the Doomsday Argument would have predicted. If we as a species can be proactive, our chances for long term survival are as high as “a few percent.” Yay?
Despite the pessimistic vibe of that conclusion, the news is actually fairly good. Going from almost zero chance to a real number is progress. Gerig’s team suggests humanity can improve its odds of long-term existence by minimizing existential threats. This might include advanced medical science and technology to divert possible asteroid strikes. Space exploration and colonization are also important actions if we want to see our society last long into the future.
It doesn’t just have to be a purely statistical argument for humanity. We’re the first species on the planet with the ability to develop new science to deal with these threats.