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Exponential Economist Meets Finite Physicist (2012)

dothemath.ucsd.edu

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Re: Exponential Economist Meets Finite Physicist (2012)

#151

Post by Retra »

sadness2 wrote: post #125

> thermodynamic limits impose a cap to energy growth lest we cook ourselves .. I’m talking about radiating the spent energy into space Huh? This seems to be a critical premise for establishing a crisis, yet it's incoherent and essentially imaginary. Ok, some ways we use energy have poor thermal efficiency. Light bulbs are the classic example, but look at the improvement from incandescent bulbs to LED's. Most uses of…

All uses of energy create heat. That's practically what it means to use energy: convert it into heat. If you create more heat than can be radiated away from Earth, then you're going to create a very unsustainable situation.

There aren't any devices that operate by moving heat around unless they create additional heat to do so, or they do no work. If you're just shuffling heat around, you're not increasing entropy, and you're not achieving any observable mechanical objective, which is pretty much the whole reason we consume energy.

Re: Exponential Economist Meets Finite Physicist (2012)

#152

Post by Balgair »

hn_throwaway_99 wrote: post #63
philipkglass wrote: post #19

I generally liked the Do The Math posts but I thought this was one of the weakest. Physicist: "Right, if you plot the U.S. energy consumption in all forms from 1650 until now, you see a phenomenally faithful exponential at about 3% per year over that whole span." It's not phenomenally faithful. There's an inflection point visible even in his large graph going back all the way to 1650. US primary energy consumption in…

Thank you thank you thank you. Honestly, this whole article had the veneer to me of "Ahh, poor silly economist..." I'm not sure if there is a great word for it, but I call it the "humble-brag equivalent of obnoxiously condescending"

It's just Physicists in general.

https://xkcd.com/793/ (scroll over text is on point here)

Especially when they get older, they try to apply the 'make a cow a sphere of water, one meter in radius' trick all sorts of other areas. The issue is that they can't deal with 'history' in real life. Most of life is chaotic and the initial conditions and stochastic nature of the world make it almost impossible to predict anything. Not all things can be made into neat theories, in fact, it's a miracle that anything does fit into neat little theories. Physicists don't like that. Typically, they start throwing around all sorts of math-y sounding words when they realize that their 'model' won't work at all (Oh, just take the Hamiltonian, that'll solve it). If that still doesn't work, they make an excuse to go to a bar as soon as possible.

Re: Exponential Economist Meets Finite Physicist (2012)

#153

Post by karmakaze »

Flaws aside a fun read.. It's a set-up when we're talking about an indefinite time scale AND bounding the discussion to Earth. Also the 1400 year time scale seems absurd. If/when for instance we have continuing orders of magnitude efficiencies in quantum computing. The physicist is debating for the wrong side.

Re: Exponential Economist Meets Finite Physicist (2012)

#154

Post by BlueTemplar »

xiphias2 wrote: post #141
BlueTemplar wrote: post #129

Earlier quoted context omitted.

No, it's basic thermodynamics : https://www.sciencealert.com/scientists-have-developed-a-sol...

This is really cool, so there's a way to radiate heat to the space much more efficiently than the sun does, which destroys the argument of the physicist.

I think you meant "much more efficiently than the Earth does" ? It weakens the argument... but I'm uncertain whether fatally or not. You still need to radiate exponentially increasing amounts of power to outer space ! This is going to mess with surface temperature sooner or later...

Re: Exponential Economist Meets Finite Physicist (2012)

#155

Post by msla »

AstralStorm wrote: post #87
bshipp wrote: post #47

Earlier quoted context omitted.

Malthusian advocates tend to view the economy as static. One of the most recent surges in that line of thinking was the worlds impending doom at the hands of Peak Oil. Every single trendline in the early 2000's showed us running into a supply wall with no possibly salvation. And here we are, not even 20 years later, and America could potentially become a net exporter of oil. economics is hard because supply and deman…

Come on. We haven't tried any other emerging solutions such as global government or full on ochlocracy. Yet always people cousin capitalistm is best we got only because it's the thing we currently have, committing the same mistake of being static, just on the higher level. Not to mention capitalism is an umbrella term with many variants making it a works claim. As if you said "the best we have is cars".

> Not to mention capitalism is an umbrella term with many variants making it a works claim.

That's part of the strength of Capitalism: You can tweak it, modify the regulatory regime, and it's still Capitalism. You don't need a revolution to modify some deep theory in order to improve how you regulate a Capitalist economy, or to adopt some ideas from the Socialist platform, like you would to modify a specific Socialist ideology.

Re: Exponential Economist Meets Finite Physicist (2012)

#156

Post by dosy »

kgwgk wrote: post #145
dosy wrote: post #118

Earlier quoted context omitted.

Right, I think the article was saying development is GDP stagnation but increasing quality nonetheless, does that about match your understanding of it? I still can't really imagine the other scenario because when I see efficiency gains I think they will lead to growth and more energy usage. Examples like "increasing CPU power should have led to faster software, but instead it lead to slower languages and larger softw…

> I think the article was saying development is GDP stagnation but increasing quality nonetheless I don't know what the article is trying to say, really. It talks about "improving the quality of life" but I'm not sure if that includes factors that are already considered in GDP calculations ( https://www.bea.gov/sites/default/files/papers/P2006-6_0.pdf ) or it's about immaterial quality of life improvements (more hapi…

Cool link, thanks I'll read it.

I'm not actually sure right now. Somehow I think that if you make those extra widgets without using more energy, then the extra people who buy and use those extra widgets will end up using more energy in doing so, and their extra purchase and use will, however incrementally, grow the economy as a whole a tiny bit, which will use that much extra energy.

So if it's growth, then it can't be static energy.

But somehow also I think that you can have static energy and not call it growth, but development, or something else like someone said before (maybe you).

What's development? I don't know. But maybe it's something like we produce 1000 widgets with more intricate decorations on them. And use no more energy doing so.

I grant that it's pretty confusing. And that's how it seems to me right now.

Thanks

Re: Exponential Economist Meets Finite Physicist (2012)

#157

Post by rotexo »

Mirioron wrote: post #53
jammygit wrote: post #33

Earlier quoted context omitted.

The biotech to terraform (or live under domes sustainably) is a longer ways off though. All the attempts to create biodomes I’ve read about have either failed or cheated on a large scale. Unless we have an Asimov-esque robot driven “colonization”, but does that fully count?

You mean caves instead of domes, right? You need protection against radiation and rock provides a lot more of that.

I think the parent was talking about all of the ecosystem services we take for granted on Earth that we still don’t know that we can reproduce artificially.

The fires in California this past fall? That represented a lot going wrong, but you could still go outside in the Bay Area and breathe.

On Mars or in space? Everything goes perfectly except for one little thing, and you are dead instantaneously.

Re: Exponential Economist Meets Finite Physicist (2012)

#158

Post by kgwgk »

dosy wrote: post #156
kgwgk wrote: post #145

Earlier quoted context omitted.

> I think the article was saying development is GDP stagnation but increasing quality nonetheless I don't know what the article is trying to say, really. It talks about "improving the quality of life" but I'm not sure if that includes factors that are already considered in GDP calculations ( https://www.bea.gov/sites/default/files/papers/P2006-6_0.pdf ) or it's about immaterial quality of life improvements (more hapi…

Cool link, thanks I'll read it. I'm not actually sure right now. Somehow I think that if you make those extra widgets without using more energy, then the extra people who buy and use those extra widgets will end up using more energy in doing so, and their extra purchase and use will, however incrementally, grow the economy as a whole a tiny bit, which will use that much extra energy. So if it's growth, then it can't…

The economy is a complex system, the only way to be sure that when you change something somewhere the energy consumption will remain constant is to put a constraint on it. You could set quotas, increase/decrese taxes to drive it to the desired targets, etc.

Imagine the system is at equilibrium at a certain output and energy usage and you discover a device than increases efficiency in the use of energy by 10%. The system could produce the same output as before using 10% less energy. But the new equilibrium won't be the same output at 10% less energy consumption, because some resources will be freed in the energy generation sector and the price of energy will go down resulting in some activities that were not economically viable before becoming viable. Maybe desalting sea water was too expensive before, but with lower energy prices and higher efficiency it does make sense, for example. You will have an increase in output but whether the new energy consumption is below or above the original level depends on the details. The latter is more likely, I guess.

Re: Exponential Economist Meets Finite Physicist (2012)

#159

Post by philipkglass »

bshipp wrote: post #69
hn_throwaway_99 wrote: post #63

Earlier quoted context omitted.

Thank you thank you thank you. Honestly, this whole article had the veneer to me of "Ahh, poor silly economist..." I'm not sure if there is a great word for it, but I call it the "humble-brag equivalent of obnoxiously condescending"

I think part of the problem is that it's easy to draw a trend-line across a batch of data you actually know about, like oil reserves or food supplies, but incredibly difficult to make educated estimates about how we will resolve constraint problems in the future. Naturally, the most rigorous analyses are going to be heavily weighted toward historical data, but will carefully ignore predicting future breakthroughs and…

It's not just the pessimistic scarcity predictions that suffer from long term extrapolation. Optimistic ones of abundance have missed the mark just as badly. Alvin Weinberg, writing in the June 1970 issue of the Bulletin of the Atomic Scientists, made an optimistic case for the very large scale use of breeder reactors -- 160 terawatts of breeder reactor capacity installed by 2050. His physics are perfectly sound. But the demand growth which this scenario assumes has not materialized.

He imagined that the world might come to demand 20 kilowatts per capita (more than twice the present per capita use in the US) and have 20 billion people living in it. Neither population growth nor energy consumption per capita growth have kept up with his estimates. Accordingly, nuclear fuel reprocessing and the breeder reactor alike have remained niche technologies without broad industrial impact. There was never enough uranium consumption growth to economically justify complicated reactors or fuel cycles.

It is difficult to make predictions, especially about the future.

Re: Exponential Economist Meets Finite Physicist (2012)

#160

Post by ThrustVectoring »

paraschopra wrote: post #111
ThrustVectoring wrote: post #84

Earlier quoted context omitted.

Yes, in current and recent economic regimes, the primary way of providing more value is simply by doing more of the similar valuable work. Instead of manual production of a shirt, a factory worker makes orders of magnitude more. Increasingly though, modern economies are shifting away from this sort of work. Instead of the energy-constrained primary and secondary sectors, more things are being done on the knowledge an…

Yes, it is true that providing a service or an information consumes less energy than materials. The real issue though is not about absolute amount of energy. The author is talking about exponential growth - the one where every year economy must grow as a percentage of existing base. At any base, even with a majority service based economy, exponential growth will hit a bottle neck. For example, take this (from https:/…

I'm well aware of exponential growth, and I'm not talking about energy efficiency. I'm talking about how economic growth is not fundamentally coupled with the material resources we consume. Like, for a long time, food production was pretty well coupled with population - if you figured out how to grow more food in your country, you'd increase its population but not its living standards. That got disconnected in the industrial revolution, and the link between your standard of living and energy consumption is increasingly getting disconnected today in modern economies.
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