It's worth bringing up The Most Important Video You'll Ever Watch [1], which the lecturer characterizes as humanity's biggest problem is our inability to understand the exponential function. Watch all 8 parts.
I have come to the conclusion that there simply are too many of us. We can probably sustain our current levels for a century, maybe two, but at some point scarce resources (and their subsequent cost) will have a devastating effect.
Basically, we need to correct our population before nature does.
As much as people point to space being our future, I simply (sadly) do not agree. While there might be plentiful resources in the asteroid belt (and on other bodies) nothing compares to how cheaply we can pull things out of the ground here on Earth. Our society is predicated on cheap, plentiful resources such that it can't survive them being several (or even one?) order of magnitude more expensive.
As far as interstellar space goes, even if we solve the reaction mass problem and have perfect (100% efficient) conversion of matter to energy, it will still be prohibitive to go to even the nearest stars.
Perhaps the simplest explanation of the Fermi Paradox is that potential growth for a starfaring civilization is geometric (being a sphere ultimately limited by the speed of light) while growth rates are exponential. And exponential will ultimately "win".
That video is a joke for anyone who has more than a superficial understanding of math. Just because a process has fit an exponential curve does not mean exponential growth is going to continue forever. Past growth patterns are fairly weak evidence of future growth patterns. ("Housing prices always go up!")
That's not to say we shouldn't fear a process that is inherently exponential in nature, like the reproduction of bacteria or a nuclear reaction going supercritical. But if the process only appears from the outside to have been growing exponentially, that's only a weak indicator that it will start behaving in an insane fashion.
In any case, it seems that as nations become more developed people stop having kids:
> Just because a process has fit an exponential curve does not mean exponential growth is going to continue forever.
Did you watch the video? This is precisely what it's talking about. Though the economy and energy usage have grown up exponentially for the past two centuries, we cannot hope that it will go on forever. Population growth isn't a concern per se, resource overconsumption and the impossibility of future economic growth are.
The world population growth rate is not exponential; in fact it has been declining for decades. It seems increasingly possible that the human population will stabilize or even decline in this century.
The strongest selection pressure in the western world is for people to spend every waking hour making babies. It sounds very likely that population growth will pick up its pace this century unless it is actively prevented.
The selection pressure is real, but it is not the only force in play. Economic pressure is acting too, and it is against raising children; they are expensive to raise to adulthood, and you cannot derive any material benefit from them. It seems to me that, in this case, the economics have much greater force than the genetics. Whatever disposition toward childbearing you inherit from your parents, whether genetic or ideological, is a small thing compared to whether circumstances make providing for them practical.
In general, when dealing with a complex system, it is not enough to know that a single force is acting on it. You need to understand all the forces, and how strong they are and how they behave. All too often, this is the case with selection pressure arguments -- supposing that the force in question is the only one in play, without any regard for whether it has the power to do the job expected of it.
I find that the best course of action is usually to look at the actual data, and see how the system really is behaving, apart from theory. Nontrivial systems very rarely meet naive expectations.
And yet all indications are that's not what happens. The most likely scenario is by mid century the world population will be in decline and continue to do so at an accelerated pace until at least 2100.
Medicine has given us control over our fertility, and the way modern societies are structured children are a financial liability.
More humans doesn't equal less resources, it equals more resources. The Earth isn't "running out" of anything, the idea of a carrying capacity for a technological species is ridiculous.
You're exemplar of this video subject: exponential growth can't go on forever, and you obviously didn't understand that. That's quite sad. Another article for reference:
Energy is the only resource that matters. With enough energy and technology we can recycle and transform whatever current raw physical materials we have available, no matter how inefficient it is.
With the population leveling off, I think the amount of physical materials needed at any one time will stop growing exponentially. Consumption will rates will still be increasing, but we can recycle the raw materials to keep the absolute amount needed within physical limits.
Sorry, I'm not an expert in that kind of stuff. But since resources don't get out of Earth, then the total loss of resources is 0.
Resource consumption is growing exponentially
Hmm, really? My computer is thinner, so is my TV (and probably my future car), I don't purchase paper any more (or almost don't purchase/use it) and I consume more digital products than physical ones. Yet, even if I purchase double of what I have the next year, I can't keep in that pace for too long.
> But since resources don't get out of Earth, then the total loss of resources is 0.
Soil washed down to the ocean is lost to agriculture, if not lost to the planet itself, for instance. I'm quite sure that the planet will be OK whatever we do; the human race, however, may disappear quite easily.
> Hmm, really? My computer is thinner, so is my TV
Yes, and to build a new computer uses infinitely more than not building it in the first place. Your old computer isn't magically transformed back into a new one, or ore.
Every transformation needs energy. As long as energy is so cheap as it can be considered free and so largely available as it can be considered like infinite, everything's fine.
Just to remind you that a "service economy" relies on large, general availability of masses of almost free energy and resources. However, energy may soon turn more expensive and rarer.
We've been in peak oil for the past few years, and the production will began to drop any time now, probably within 3 to 5 years. There are no credible alternative to cheap fossil fuels, unfortunately, for most of their uses (transport, plastics, chemicals, fertilizers...).
So far, the way the world economy is currently organized cannot survive a massive change in energy availability. Particularly with the current accent put on economic growth. By definition, economic growth must stop at some point, by lack of resources, then go down. In the near future, economic recession will be the normal state of matters. How will we manage it? Without sinking into chaos? I really have no idea.
> Perhaps the simplest explanation of the Fermi Paradox is that potential growth for a starfaring civilization is geometric (being a sphere ultimately limited by the speed of light) while growth rates are exponential. And exponential will ultimately "win".
I read a paper within the last few months that used simulated expansion into a galaxy to debunk that idea. The fallacy is that growth is continuous and ceases simultaneously across a civilization. The (simulated) reality is that only a tiny percentage of frontier colonies need to survive to prevent extinction and eventually resume growth.
I wish I could find the paper. Anyone know the one I'm talking about?
Don't remember if the video addresses this (saw it years ago), but aren't most exponentials just part of the ever-present logistic curve? ( http://en.wikipedia.org/wiki/Logistic_function )
I have come to the conclusion that there simply are too many of us. We can probably sustain our current levels for a century, maybe two, but at some point scarce resources (and their subsequent cost) will have a devastating effect.
Basically, we need to correct our population before nature does.
As much as people point to space being our future, I simply (sadly) do not agree. While there might be plentiful resources in the asteroid belt (and on other bodies) nothing compares to how cheaply we can pull things out of the ground here on Earth. Our society is predicated on cheap, plentiful resources such that it can't survive them being several (or even one?) order of magnitude more expensive.
As far as interstellar space goes, even if we solve the reaction mass problem and have perfect (100% efficient) conversion of matter to energy, it will still be prohibitive to go to even the nearest stars.
Perhaps the simplest explanation of the Fermi Paradox is that potential growth for a starfaring civilization is geometric (being a sphere ultimately limited by the speed of light) while growth rates are exponential. And exponential will ultimately "win".
[1]: http://www.youtube.com/watch?v=F-QA2rkpBSY