A little place of calm

How long will humanity survive?

I'm reading a book called "The Goldilocks Enigma" by Paul Davies. It discusses why it is that the universe seems to be so finely tuned to life. It explains all the 'coincidences' that have turned up in cosmology and quantum physics, the constants that we experience such as the strength of gravity, the size of protons, the power of the electromagnetic force, etc, and describes what would happen if they were slightly different.

The book has pointed out the one glaring exception to the "principle of mediocrity" that says the universe is pretty much the same wherever you look: the exception being that we are here and we have never yet observed intelligent life elsewhere! Why should that be? It continued by covering in detail the theory of multiple pocket universes, perhaps an infinite number of them, creating a collective multiverse. I am just coming on to the part about simulated universes and whether we would even know if we were in a simulation. All this i find very fascinating.

One thing made me stop and think this morning. It was just a little aside to another point the author was making. I'll quote the context and bold up the bit that interested me the most.

While the simulation argument was restricted to a single universe, it was always possible to wriggle out of the uncomfortable conclusion that this might be a simulation by arguing that no civilizations are likely to reach the point of achieving such stupendous computational power. For example, there are many reasons why humanity may not survive for more than a few centuries beyond the present, and that may not be long enough for conscious computers to be developed. If a similar fate were to befall any other intelligent beings who might be located elsewhere in the universe, then simulations, while still a possibility in principle, might never be achieved in practice.

Paul Davies, The Goldilocks Enigma, page 208.

There it is. Just a little snippet with no elaboration. Just a cold hint that our species might not be around for very much longer. A footnote references "Our Final Century" by Martin Rees. I think i should read that book soon!

The reason it caught my attention is that i have been thinking for a while that we might be heading for an early demise. A point made in "Conversations With God" is that our technological advances have now exceeded our sociological development. We have the ability to annihilate our entire species (and many of the others) if we misuse our technology. The scary thing is, all it takes is a few wrong decisions by a minority of people with great influence. Look at the Iraq war. I was one of 36 million people^[citation] who protested against it before the war began. It did no good. We couldn't change the minds of the people who decided it would happen.

If it's not a devestating war it'll be run-away climate change, or over-population leading to world hunger, or an asteroid will hit the planet and wipe us out. In the long-term i think the only way to ensure the prolonged survival of our species is to spread ourselves out across other planets in the galaxy. Of course, eventually we would have to do that anyway: in 5 billion years time the sun will run out of fuel. But how soon can we start migrating to different planets? Current estimates suggest not very soon at all!

This is the first hint i've come across that says our time left could be measured in centuries. In "Stardust", Stephen Welch says that the average life-span of a land-based species is 5 million years. We humans have only been around for the last 200,000 years. It's a terribly young age for a species to die!

But if we are wiped out, what happens next? I believe that life will go on in some form. Life is very resilient, once started, it's very hard to kill it. No matter what happens to the planet, even if we can't survive, something will. But then what of all our culture, our literature, our art, our technology? Everything that we've produced will eventually fade and crumble without us here to preserve it. Does that matter? Wouldn't it be a shame if another intelligent species were to come to our planet in a million years' time and find no trace of our existence?

What are we really trying to achieve here, anyway? I mean really long-term. Eventually our entire universe will freeze out as the last stars extinguish all the available fuel. We know that the human race cannot survive indefinitely, at least, not unless we can figure out a way to jump to a different universe, all of which (if they exist at all) are probably receding from us faster than the speed of light! Even if we put our consciousness into a simulated reality, it cannot outlast the life of the universe. Everything needs energy, and the second law of thermodynamics will be our ultimate downfall. "The Last Question" by Isaac Asimov, written in 1956, makes this point profoundly. It's a good read; i enjoyed it recently.

Ah, where am i going with this? I know we as a species won't last forever, I don't want our entire existence to be meaningless in the end but i can't work out what it would take to make it meaningful on a cosmic scale. I think that a few hundred years is not a long time for homo sapiens to have left, and i hope we can get past our selfishness and childishness. I hope that our final end isn't caused by our own silly fault.