Posts
With President Trump and North Korea's Supreme Leader, Kim Jong-un engaged in a nuclear-armed chest-thumping competition, and the Bulletin of Atomic Scientists' Doomsday Clock now just 2 and a half minutes before midnight, the possibility that our civilization may annihilate itself is hard to deny. And that doesn't count the risks from climate change, biodiversity loss, runaway artificial intelligence and other human-caused developments.
If we're in this fix just 350 years after the start of the Scientific Revolution and just 7 decades into the Atomic Age, how much longer can we reasonably expect our vaunted but fragile civilization to last?
Not all that long, says Daniel Whitmire, a retired astrophysicist now teaching mathematics at the University of Arkansas. Whitmire bases his argument on one of the long-established principles of philosophy and science, the principle of mediocrity.
The principle of mediocrity makes the reasonable assumption that we're more likely to observe or experience common events than uncommon ones. This idea has helped us to recognize that Earth is not the center of the universe, that our solar system is just one among billions in our galaxy, and that the Milky Way is just one of hundreds of billions of galaxies in the observable universe.
Whitmire notes that we are Earth's first technologically advanced species and that it's early in our possible technological evolution. If we are in fact typical of technological civilizations in general, that leads to two unhappy conclusions--technological civilizations don't last long before destroying themselves, and when they do, they take their planet's biosphere down with them.
To grasp Whitmire's reasoning, we need to think like a statistician, in terms of a distribution of technological civilizations with different lifespans. Imagine a big bowl full of marbles, each representing a technological civilization somewhere in our galaxy. So far, we've only gotten to reach into the bowl once, and out came our particular civilization. What can that one draw tell us about the rest?
Whitmire points out that if most technological civilizations last hundreds of thousands or millions of years, our few-hundred-year experience with technology would be very atypical. However, Whitmire calculates, if most technological civilizations last no more than a few thousand years, we would be typical, falling in the middle 95 percent of the distribution, although among the youngest.
The implication from the most likely distribution--most technological civilizations don't last very long, say 500 years or so.
Five hundred or a thousand years may seem like a long time from the perspective of a human lifespan, but it's extremely short compared to the age of the Earth and the Earth's biosphere. Whitmire notes that, left to itself, Earth's biosphere can be expected to survive for at least another billion years. If humans (or other technological species that might evolve here) went extinct, but didn't damage the biosphere in the process, there would be time for many subsequent civilizations to evolve. But that would again make us, as first-timers, atypical.
The implication--when technological civilizations die, they destroy their planet's biosphere, or at least degrade it to a level that doesn't give the planet enough time to evolve a second technological civilization. To paraphrase F. Scott Fitzgerald, there are no second chances for planets that evolve technological civilizations.
In short, if we are typical, than other technological civilizations would, like us, be early in in their potential life-spans (implying a short lifespan in general), and be the first on their planet (implying no subsequent technological civilizations, and hence destroyed or massively degraded biospheres).
Whitmire concludes:
Our inferences regarding the fate of the typical technological species are based
on two observations and essentially one assumption. The observations are that
our technological species is (1) the first such species to evolve on Earth and
(2) early in its potential technological evolution. The assumption is that the
Principle of Mediocrity applies to the reference class of all extant technological
species. Given this assumption, the suggested inference is that the typical tech-
nological species has a short lifetime and that their extinction coincides with
the extinction of their planetary biosphere.
Of course, we can always hope that we're not just a typical technological civilization, but one that's smart enough not to annihilate ourselves along with Earth's biosphere. That would be great, but if we follow Whitmire's logic, the odds are against it.
---------------
You can access Whitmire's article in the International Journal of Astrobiology at this URL.
You can read a slightly different but very clear exposition of these ideas here.
---------------
If you enjoyed this post, please sign up to receive email alerts or to follow zerospinzone.blogspot.com
 |
| The Doomsday Clock may tick for most technological civilizations Credit: Bulletin of the Atomic Scientists |
Not all that long, says Daniel Whitmire, a retired astrophysicist now teaching mathematics at the University of Arkansas. Whitmire bases his argument on one of the long-established principles of philosophy and science, the principle of mediocrity.
The principle of mediocrity makes the reasonable assumption that we're more likely to observe or experience common events than uncommon ones. This idea has helped us to recognize that Earth is not the center of the universe, that our solar system is just one among billions in our galaxy, and that the Milky Way is just one of hundreds of billions of galaxies in the observable universe.
Whitmire notes that we are Earth's first technologically advanced species and that it's early in our possible technological evolution. If we are in fact typical of technological civilizations in general, that leads to two unhappy conclusions--technological civilizations don't last long before destroying themselves, and when they do, they take their planet's biosphere down with them.
To grasp Whitmire's reasoning, we need to think like a statistician, in terms of a distribution of technological civilizations with different lifespans. Imagine a big bowl full of marbles, each representing a technological civilization somewhere in our galaxy. So far, we've only gotten to reach into the bowl once, and out came our particular civilization. What can that one draw tell us about the rest?
Whitmire points out that if most technological civilizations last hundreds of thousands or millions of years, our few-hundred-year experience with technology would be very atypical. However, Whitmire calculates, if most technological civilizations last no more than a few thousand years, we would be typical, falling in the middle 95 percent of the distribution, although among the youngest.
The implication from the most likely distribution--most technological civilizations don't last very long, say 500 years or so.
Five hundred or a thousand years may seem like a long time from the perspective of a human lifespan, but it's extremely short compared to the age of the Earth and the Earth's biosphere. Whitmire notes that, left to itself, Earth's biosphere can be expected to survive for at least another billion years. If humans (or other technological species that might evolve here) went extinct, but didn't damage the biosphere in the process, there would be time for many subsequent civilizations to evolve. But that would again make us, as first-timers, atypical.
The implication--when technological civilizations die, they destroy their planet's biosphere, or at least degrade it to a level that doesn't give the planet enough time to evolve a second technological civilization. To paraphrase F. Scott Fitzgerald, there are no second chances for planets that evolve technological civilizations.
In short, if we are typical, than other technological civilizations would, like us, be early in in their potential life-spans (implying a short lifespan in general), and be the first on their planet (implying no subsequent technological civilizations, and hence destroyed or massively degraded biospheres).
Whitmire concludes:
Our inferences regarding the fate of the typical technological species are based
on two observations and essentially one assumption. The observations are that
our technological species is (1) the first such species to evolve on Earth and
(2) early in its potential technological evolution. The assumption is that the
Principle of Mediocrity applies to the reference class of all extant technological
species. Given this assumption, the suggested inference is that the typical tech-
nological species has a short lifetime and that their extinction coincides with
the extinction of their planetary biosphere.
Of course, we can always hope that we're not just a typical technological civilization, but one that's smart enough not to annihilate ourselves along with Earth's biosphere. That would be great, but if we follow Whitmire's logic, the odds are against it.
---------------
You can access Whitmire's article in the International Journal of Astrobiology at this URL.
You can read a slightly different but very clear exposition of these ideas here.
---------------
If you enjoyed this post, please sign up to receive email alerts or to follow zerospinzone.blogspot.com
No comments:
Post a Comment