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What percentage of people are alive today?

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Re: What percentage of people are alive today?

#71

Post by Retric »

TheSOB88 wrote: post #54
brazzy wrote: post #51

Earlier quoted context omitted.

As long as the measure of productivity corresponds to something physical (which even bits on a harddisk are), then an exponential increase in productivity (as we have seen in the past) would eventually require humanity and its products to form a sphere whose radius grows faster than the speed of light. Do you agree that that is a pretty hard limit?

I think you may have skipped some steps... Could you fill in the middle a bit? I'm confused.

Let's suppose the amount of physical goods produced increases 1% each year. Let's add that as physical objects they take up some space minimum amount of time. Now let's add that humanity is spreading out in all directions at the speed of light. If humans cover 1 light year of space they can expand faster than the new amount of stuff. However Volume = 4/3 pi * radius ^ 3 so what happens when humanity covers 1,000 light years. Well, next year they need to put 1% more stuff into 1002^3 / 1000^3 = 0.6% more space which means they need to increase the density which at some point means you have a black hole.

PS: 1% growth per year seems slow and sustainable but in 20,000 years your talking about 2.7 with 86 zeros after it. Start with 1 atom for one second and compare it with every atom in the earth for a year and your only at 4.2 with 57 zeros. So if the total economic output of humanity was 1 atom we could not sustain 1% economic growth per year for 30,000 years.

Edit: This assumes that the economy is based on physical goods, if we assume intangibles can take up 99.99...9% of the economy then 1% growth is possible for long periods of time even if it's somewhat meaningless.

Re: What percentage of people are alive today?

#72

Post by Unseelie »

tel wrote: post #25
mlinsey wrote: post #21

Earlier quoted context omitted.

Of course Earth must have some finite carrying capacity, but that's only terrifying if you assume that "The Crunch" is the only way to bring population growth to a halt. Population growth is already zero or negative in most developed countries if you remove the effects of immigration. If this becomes a consistent rule for all countries once they become fully developed, the real question is not whether we can sustain…

I agree that such a state doesn't (a) seem impossible or (b) seem untenable if we have sufficient technological advances (solving fusion ignition, perhaps). What kind of trajectory takes us from here to there (or to a place dense with similar stable solutions) without going through war and famine? Or, how does a developed nation survive in relative bounty surrounded by nations undergoing severe war and famine?

The first question is very difficult to answer..the second?

>Or, how does a developed nation survive in relative bounty surrounded by nations undergoing severe war and famine?

Brutality and self interest.

Re: What percentage of people are alive today?

#73

Post by Symmetry »

6ren wrote: post #67
spindritf wrote: post #41

Earlier quoted context omitted.

> he merely pointed out (correctly) that there will eventually be a limit to productivity I don't understand this point. Why would there be a limit to productivity, especially with machines and computers to leverage our efforts thousandfold and more? And how could anyone know that such limit exists, even if it is actually reached one day? That would require predicting any possible innovation of the future.

Yes, I think a limit on productivity amounts to a limit on knowledge. Does knowledge have a limit? There's no evidence for it; all our present mathematics of complexity suggests not (but it's possible one will be discovered...) However, energy needs do seem to increase with productivity, and there's limit on how much energy we can get from the sun (a dyson sphere encloses the sun, capturing all its energy). But there…

There are actually mathematical limits to the amount of information that can be stored within a given volume, the Bekenstein bound, which is a lot like a limit to knowledge.

Re: What percentage of people are alive today?

#74

Post by Unseelie »

jgorham wrote: post #19
tel wrote: post #9

Am I the only one absolutely terrified by that number? Malthus wasn't wrong in principle, just in timescale. It's clear that technologies have improved Earth's human carrying capacity, but I don't know any method to claim that an S-shaped curve isn't inevitable. It's sounds science fiction-ey, but I don't understand how you can see data like this and then defund NASA.

One interesting fact regarding population growth is that worldwide, having children on aggregate is a inferior good: if parts of Africa and Southeast Asia can make some significant gains in the next few decades, we will likely see population peak sometime this century.

Children can't be compared to goods. There's biological things at worth beyond self interest. That is to say, people want children, even though its not in their self interest.

I'd posit, if you were to try to assign children a status as a good in a wealthy culture, they'd be a luxury good. They cost a great deal, are effectively useless, but still desired.

Re: What percentage of people are alive today?

#75

Post by Unseelie »

melling wrote: post #48

Now if we could get every person educated and productive, we could solve tens of billions of problems. Unfortunately, most people are just trying to survive.

We'd also have to give them problems to solve outside of 'how do I raise my children' or 'feed myself' or 'entertain myself'...or is that what you meant by productive?

Re: What percentage of people are alive today?

#76

Post by ck2 »

It's an ugly thought but I think more people than ever are trying to create a biological retirement plan - having multiple children to take care of them later on.

Trying not to make a moral judgment call on that and hoping I am just being too cynical. But think about how many people you know with children and then count the number that have conscientiously chosen to have only one.

Re: What percentage of people are alive today?

#77

Post by btilly »

michaelchisari wrote: post #27
btilly wrote: post #15

Earlier quoted context omitted.

You are not alone. If you want to get more scared, read http://www.amazon.com/Collapse-Societies-Choose-Fail-Succeed... . Interestingly from the population statistics alone it is possible to make an argument about the total likely future number of humans that will live. There is debate about whether the reasoning is correct, but it is at least suggestive. See http://en.wikipedia.org/wiki/Doomsday_argument for more.

And maybe once you're done with that, you can read a rebuttal of sorts: http://www.amazon.com/Coming-Population-Crash-Planets-Surpri...

I am familiar with the arguments suggesting that population growth is self-limiting. I am also aware that the spread of birth control is breeding people whose will fail to use it. They may be a small portion of the overall population, but any portion that is on an exponential curve when the rest are not is bound to eventually dominate the population.

Malthus has been postponed for centuries. And may well be postponed for more centuries. But unless resources grow exponentially, Malthus eventually will have the last laugh.

Re: What percentage of people are alive today?

#78

Post by btilly »

ellyagg wrote: post #32
btilly wrote: post #15

Earlier quoted context omitted.

You are not alone. If you want to get more scared, read http://www.amazon.com/Collapse-Societies-Choose-Fail-Succeed... . Interestingly from the population statistics alone it is possible to make an argument about the total likely future number of humans that will live. There is debate about whether the reasoning is correct, but it is at least suggestive. See http://en.wikipedia.org/wiki/Doomsday_argument for more.

I don't think the Doomsday Argument is that interesting. It may be trivially true, but it doesn't tell us anything interesting or predictive. All it says is that the chronology of human existence is too complicated for us to calculate. That being the case, our working assumption can only be that we're at the midpoint of our species population line. But, keep in mind that this estimate is really, really horrible, it's…

I don't think the Doomsday Argument is that interesting. It may be trivially true, but it doesn't tell us anything interesting or predictive.

If it is true, it can let us put probabilistic upper bounds on the future of the human race. For instance with 99.99999% likelihood I can tell you that the human race will fail to succeed in expanding colonization of other stars. As much as we may dream of the stars, we will never reach them.

Similarly the odds of our maintaining our current population levels for the next thousand years is something like 40%. That is both interesting and predictive. Its meaning, however, is highly debatable.

Re: What percentage of people are alive today?

#79

Post by chipsy »

FrojoS wrote: post #56
petercooper wrote: post #31

Not to detract from the insight but: Until very recently life expectancy at birth hovered between 20 and 35 years, but in the past century it has risen to 67 years Most of this increase has been due to a precipitous crash in infant mortality, rather than a soaring increase in the median life expectancy. For example, even in the 1500s it seems a well-to-do Englishman (who lived a somewhat more hazardous life medically…

All true, though, as far as I know, hunters and gathers who manage to survive childhood still die quite early, no? [1] They appear very healthy but thats partly because there are pretty much no grand parents. I might be wrong about this. Also, a diet high in animal protein might make you very fit but it is thought to be a cause for cardiovascular disease [2]. Actually, afaik, this is the reason why government still g…

Nutrition isn't the only issue. Hunter-gatherers have a much higher chance of a violent death; not just because of the risks of hunting, but because tribal warfare drafts the majority of able-bodied men. Even the ritualized warfare commonly used among present-day hunter-gatherers is likely to cause deaths.

http://en.wikipedia.org/wiki/War_Before_Civilization

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