The other day I started thinking when the earliest possibly time our universe could given rise to the first technological singularity. What are the necessary preconditions, and when is the earliest time those pre-conditions emerged?
Let’s examine the evidence and make some conjectures.
In order to determine the earliest theoretical timeframe, we need to know what the necessary precursors of a technological singularity are. Since the Earth and the emergence of our own civilization is the only example we have, we’ll assume that life and therefore technological civilization requires a planet as a necessary prerequisite for a technological singularity.
So when were these first planets formed? Since planets require heavy elements, the earliest possible time would be right after a supernova explosion of a first-generation star. Since these first generation stars were composed entirely of hydrogen and helium, the heavier elements necessary for planetary formation were not available yet. However, thanks to nucleosynthesis in the core of these stars, these necessary heavier elements were created at a furious pace. These first generation stars first appeared 160 million years after the Big Bang. The most short-lived of these were the blue giants. After the first of these blue stars exploded, all of the material necessary for planetary formation were now available. So these second generation stars had all the heavier elements necessary for planetary disk accretion and formation.
According to this story,
http://www.nytimes.c...c7c1289&ei=5070
the Hubble Space Telescope found tantalizing evidence that planets first appeared much earlier in cosmic history, around 12.7 billion years ago, and therefore may be more abundant than previously suspected. Since we know both the earth and sun are each 4.5 billion years old, the earliest possible time earth like planets could have formed was 1 billion years after the big bang.
So from here we need to examine Earth’s history to determine the next part of our equation. This is where a bit of guesswork is required.
There is observational evidence that archaebacteria, the first type of life, were around as early as 3.97 billion years ago. Then for the next 2.2 billion years, life on earth consisted of nothing more than anaerobic bacteria and archaeans. Then about 1.8 billion years ago eukaryotic cells appeared as fossils too. With the beginning of the Middle Proterozoic 1.8 billion years ago, comes the first evidence of oxygen build-up in the atmosphere. This global catastrophe spelled doom for many bacterial groups, but made possible the explosion of eukaryotic forms. These include multicellular algae, and toward the end of the Proterozoic, the first animals.
With the Cambrian Explosion soon after, all the major phyla of life we know today emerged. Between the Cambrian explosion 543 million years ago and today there have been 5 great extinctions, the last of which was 65 million years ago, when 90% of life, including all the Dinosaurs, were wiped out by a comet. From the lowly 10% that was left emerged almost all the complex life we see today.
The real question now is could this 3.97 billion year history of life have happened at an accelerated rate? We know the first 2.2 billion years of life consisted of nothing more than simple anaerobic bacteria and archae, and the next 1.2 billion years single-celled eukaryotic oxygen-breathing bacteria. So for the first 3.4 billion years the degree of evolutionary change was almost non-existent. There is no reason to suspect the emergence of eukaryotic cells couldn’t have happened sooner, perhaps as earlier as a few million years after the first bacteria. The mechanisms underlying these punctuated periods of evolution are still largely unknown, so it’s mostly conjecture. But lets take a crack at it anyway.
I think most of this period’s stagnation was the result bad luck, or perhaps a lack of good luck. A low probability of correct mutations necessary for the emergence of multi-cellular life may be the reason it took so long. We know that quadrillions of bacteria were spread out all over the earth, and only after 3.4 billion years of relative stagnation did it eventually give rise to the first multi-cellular organisms. If this is the result of statistics rather than a slow necessary build up of a complex ecology, then life multi-cellular life could have emerged shortly after the first life appeared, maybe as little as a few millions of years, rather than 3.4 billion. Then again, mutli-cellular life could be so rare, that only 1 out of a million bacteria bearing planets give rise to multi-cellular life during the lifetime of its parent star.
It’s possible that multi-cellular creatures could have emerged as early as 3 billion years ago, giving rise to the equivalent of the Cambrian explosion 2.5 billion years earlier than it did. This leaves the last 543 million years after the Cambrian Explosion until now. Perhaps if we had a larger gas giant in a orbit closer than Jupiter’s, there would've been less asteroid and cometary impacts, further accelerating the right kinds of conditions for life to occur. In the scheme of things, this time frame is small enough that it doesn't matter much with a 13.7 billion year timeframe. So for the sake of this essay, I'll assume that 500 million years is the minimum time necessary for complex technological civilization to evolve from the first appearance of multi-cellular life.
Assuming my 2.5 billion year compression of the history of life is possible in a planetary system with the right conditions, this means technological civilization on the Earth could have occurred as early as 2 billion years after the formation of Earth itself.
Since we know that the first planets were forming as early as 12.7 billion years ago, and using earth’s history as our example, this means the first technological singularity could have occurred as early as 10.7 billion years ago, or just 3 billion years after the Big Bang. If we take out my conjectured time compression of evolution, we add an additional 2.5 billion years, giving us 5.5 billion years after the big bang.
This leaves us with a theoretical minimum of 8.2 – 10.7 billion years ago, that a technological singularity could have first occurred.
Comments, feedback, flaws?
Edited by planetp, 26 March 2004 - 03:29 AM.