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Exponential Economist Meets Finite Physicist (2012)

dothemath.ucsd.edu

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Re: Exponential Economist Meets Finite Physicist (2012)

#91

Post by cinquemb »

AstralStorm wrote: post #90
cinquemb wrote: post #81

Earlier quoted context omitted.

>- and current model cars are probably just about there- Very true, in order to get more progress, one would have to develop systems that are sufficiently different and more efficient at some level which may be odds with how we currently allocate resources.

Such as series hybrids and electric cars. (Dropping complex transmission for batteries, but using a more efficient engine.) At some point though friction against road and minimum weight for safety and comfort come into play, and once you optimize these you end up with a train. :) It's the same problem electronics face right now, when they really butt into quantum physics and consequently have huge yield issues - and…

Neither of which are physical limitations, just limitations on our understanding of physics and our ability to apply them to issues of the day. We are always in the process of trying to determine what the limits of physics actually are (modulo a given societies acceptance level of such experimentation and mechanisms to explore such).

Re: Exponential Economist Meets Finite Physicist (2012)

#92

Post by AstralStorm »

mr_toad wrote: post #35
jbay808 wrote: post #13

Earlier quoted context omitted.

This is why, as all economists agree, measurements of economic growth are completely arbitrary and the economy hasn't changed in any meaningful way that can be called "growth" since the middle ages. ... Oh, wait, or maybe growth actually can be expressed as a quantifiable concept? In this case, the author chooses energy as an objective measurement, because all economic transactions must consume energy in order to occ…

> the author chooses energy And is thereby begging the question. Economists value goods using prices.

Prices fluctuate a lot, embodied energy and production energy can fluctuate for the same thing too, but trend down until they got the ceiling or whole branch of technology is phased out.

You could take some representative branches of housing to build what is called an energy basket, using similar method used to calculate PPP.

Such rough methods would include communication, transportation, housing, clothing, food, self-expression and a few more mostly timeless needs that haven't changed for many centuries.

The problem is of accurate representative sampling of each category. That gets easier the closer we are to modernity with big data gathering.

The methodology would survive start from before bronze age even, I think.

Re: Exponential Economist Meets Finite Physicist (2012)

#93

Post by AstralStorm »

cinquemb wrote: post #91
AstralStorm wrote: post #90

Earlier quoted context omitted.

Such as series hybrids and electric cars. (Dropping complex transmission for batteries, but using a more efficient engine.) At some point though friction against road and minimum weight for safety and comfort come into play, and once you optimize these you end up with a train. :) It's the same problem electronics face right now, when they really butt into quantum physics and consequently have huge yield issues - and…

Neither of which are physical limitations, just limitations on our understanding of physics and our ability to apply them to issues of the day. We are always in the process of trying to determine what the limits of physics actually are (modulo a given societies acceptance level of such experimentation and mechanisms to explore such).

We actually know the limits of information density from bottom, that puts a bottom floor on electronics unless someone really figures out new physics. Likewise we know bottom floor for efficiency during transit in atmosphere under same condition.

Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.)

There does exist a series of absolute limits on Earth, such as capacity for growing food limited on sunlight, water and availability of specific minerals. Inserting more planets adds to that limit with a transportation losses... Unknown exactly but bottom floor is easy to figure out for spaceflight and mining (unless teleportation).

You can even limit maximum size of "life speed" cone around Earth which would be the maximum distance we can get things from during lifetime of any person. (Unless immortality or teleportation or high multiplier FTL.)

Re: Exponential Economist Meets Finite Physicist (2012)

#94

Post by acchow »

dosy wrote: post #59
acchow wrote: post #52

Absolutely there are thermodynamic limits to energy "use" on the planet. But isn't it obvious that we will expand into space stations and then eventually onto other planets? > But if energy became arbitrarily cheap, someone could buy all of it, and suddenly the activities that comprise the economy would grind to a halt. This segment contained a number of logical leaps that I can't agree with. It is possible for energ…

I think it's a condensed version of saying: If we have finite energy at a fixed price (of say 1% of GDP in total cost), then either the rest of the GDP (which is not energy) does not grow, and so the demand for that energy (and so its price) remains the same, or it tries to grow (and cannot "is stuck") because growth will increase demand for the energy and therefore drive up prices, but since it is energy and fundame…

> but since it is energy and fundamental to everything, all prices will go up, so we will have inflation, but inflation is not growth.

Oh ok... I see why I got lost. In my head I didn't hold the assumption that "all growth necessarily must consume more energy". This is assumed throughout the article until the Epilogue.

But if you drop this assumption, then I don't think the "it's just inflation not growth" holds anymore.

Re: Exponential Economist Meets Finite Physicist (2012)

#95

Post by cinquemb »

AstralStorm wrote: post #93
cinquemb wrote: post #91

Earlier quoted context omitted.

Neither of which are physical limitations, just limitations on our understanding of physics and our ability to apply them to issues of the day. We are always in the process of trying to determine what the limits of physics actually are (modulo a given societies acceptance level of such experimentation and mechanisms to explore such).

We actually know the limits of information density from bottom, that puts a bottom floor on electronics unless someone really figures out new physics. Likewise we know bottom floor for efficiency during transit in atmosphere under same condition. Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.) There does exist…

Such limits are derived from our current understanding, of which one would have probably given a completely different answers 150 years ago based on our understanding then.

>Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.)

Well maybe we haven't seen them because we didn't know how to look… recently declassified FLIR from US navy reporting archives suggest things that we haven't typically seen in nature in the past, can be seen.

>There does exist a series of absolute limits on Earth, such as capacity for growing food limited on sunlight, water and availability of specific minerals.

True, but what is the purpose of any of these things, and do we currently pursue the most efficient ways of doing such for those ends in a way that we cannot think about it anymore?

Re: Exponential Economist Meets Finite Physicist (2012)

#96

Post by AstralStorm »

cinquemb wrote: post #95
AstralStorm wrote: post #93

Earlier quoted context omitted.

We actually know the limits of information density from bottom, that puts a bottom floor on electronics unless someone really figures out new physics. Likewise we know bottom floor for efficiency during transit in atmosphere under same condition. Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.) There does exist…

Such limits are derived from our current understanding, of which one would have probably given a completely different answers 150 years ago based on our understanding then. >Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.) Well maybe we haven't seen them because we didn't know how to look… recently declassified…

Correct, the are multiple ways to extend each of the limits, even one based on food, however mathematical limits on complexity exist and are really hard to surpass. On the upside, we're really far from them. Smart matter is not quite in our grasp.

Once we figured out information-theoretic entropy we got tools to set bottom limits on everything. I'm not entirely sure when, but Kolmogorov was quite some time ago. The math is in good company of Shannon and Fischer.

Remember that reducing costs by not doing something has risks. Existential risks in fact. (E.g. reliance on a single source of energy without fallback.)

Re: Exponential Economist Meets Finite Physicist (2012)

#97

Post by cinquemb »

AstralStorm wrote: post #96
cinquemb wrote: post #95

Earlier quoted context omitted.

Such limits are derived from our current understanding, of which one would have probably given a completely different answers 150 years ago based on our understanding then. >Breaking both in any major way would require or beget actual teleportation. (Which unlike electricity or moving in atmosphere has not been seen in nature.) Well maybe we haven't seen them because we didn't know how to look… recently declassified…

Correct, the are multiple ways to extend each of the limits, even one based on food, however mathematical limits on complexity exist and are really hard to surpass. On the upside, we're really far from them. Smart matter is not quite in our grasp. Once we figured out information-theoretic entropy we got tools to set bottom limits on everything. I'm not entirely sure when, but Kolmogorov was quite some time ago. The m…

Kolmogorov was about 90 years ago. Shannon, similar. Neither of their accomplishments will limit future accomplishments and understanding (except those bound slavishly to such frameworks [as good as they may be today in certain applications])

>Existential risks in fact. (E.g. reliance on a single source of energy without fallback.)

Existential risks for oil companies investors or CSP investors?

Re: Exponential Economist Meets Finite Physicist (2012)

#98

Post by mnl »

cinquemb wrote: post #89
stouset wrote: post #86

Earlier quoted context omitted.

This is covered in an earlier post of his. At current growth rates, we’ll start noticeably heating the Earth in only a few hundred years. Not from the greenhouse effect, but from literally saturating the Earth’s capacity to radiate excess energy as heat into space. This is a raw physical limitation. How we use and how we generate the energy are irrelevant details. The only thing that matters is Earth’s ambient temper…

> How we use and how we generate the energy are irrelevant details. Just as irrelevant as assuming the basis behind current growth rates where it is impossible to mitigate agaisnt "literally saturating the Earth’s capacity to radiate excess energy as heat into space". All of this is based on assumptions. You can't just accept one set of assumptions that underlie a model and throw out others that could refute it (well…

That's the great thing about thermodynamics, you can determine bounds for a few magnitudes in a physical system ignoring all the details about its evolution.

For instance you can't disrupt the 2nd law, so at some point it's actually true that it is impossible to mitigate overheating and you won't be able to improve Stefan-Boltzmann law (except for increasing our emissivity, at night I'd guess). You can try to play with mass transfer but more thermal escape is not a good idea and a heat exchanger with extraterrestrial masses won't work.

I know it's hard to take and that physicists sound arrogant when they do this, but that's how it is.

Re: Exponential Economist Meets Finite Physicist (2012)

#99

Post by cinquemb »

mnl wrote: post #98
cinquemb wrote: post #89

Earlier quoted context omitted.

> How we use and how we generate the energy are irrelevant details. Just as irrelevant as assuming the basis behind current growth rates where it is impossible to mitigate agaisnt "literally saturating the Earth’s capacity to radiate excess energy as heat into space". All of this is based on assumptions. You can't just accept one set of assumptions that underlie a model and throw out others that could refute it (well…

That's the great thing about thermodynamics, you can determine bounds for a few magnitudes in a physical system ignoring all the details about its evolution. For instance you can't disrupt the 2nd law, so at some point it's actually true that it is impossible to mitigate overheating and you won't be able to improve Stefan-Boltzmann law (except for increasing our emissivity, at night I'd guess). You can try to play wi…

"Wavelength- and subwavelength-scale particles,[1] metamaterials,[2] and other nanostructures are not subject to ray-optical limits and may be designed to exceed the Stefan–Boltzmann law."

Re: Exponential Economist Meets Finite Physicist (2012)

#100

Post by dosy »

acchow wrote: post #94
dosy wrote: post #59

Earlier quoted context omitted.

I think it's a condensed version of saying: If we have finite energy at a fixed price (of say 1% of GDP in total cost), then either the rest of the GDP (which is not energy) does not grow, and so the demand for that energy (and so its price) remains the same, or it tries to grow (and cannot "is stuck") because growth will increase demand for the energy and therefore drive up prices, but since it is energy and fundame…

> but since it is energy and fundamental to everything, all prices will go up, so we will have inflation, but inflation is not growth. Oh ok... I see why I got lost. In my head I didn't hold the assumption that "all growth necessarily must consume more energy". This is assumed throughout the article until the Epilogue. But if you drop this assumption, then I don't think the "it's just inflation not growth" holds anym…

I had to parse that part a few times to get it myself, when I saw you didn't get it too I could relate.

Then I had to think a few times about what you gave in response! It seems this part of the topic is quite involved. I think I get some of it now.

If you drop the assumption that grow takes energy, then no extra demand on energy from growth, then no price increase on energy, then no inflation, and so it's just growth, not inflation. Agreed.

But when you and me are examining it like this...the whole situation described by that sentence starts to seem a little contrived to me. Seems there's a lot of error bars on each of the assumed connections in that causal chain, that could lead that path to branch at each of them into many other possible paths, rather than just the one path that condensed sentence proposes.

I still have a hard time imagining a growth that doesn't use more energy (except the one defined in that article as "development", which seems to be a more sophisticated/involved use of existing resources, rather than extracting/creating more new (primary) resources.)

If you could elaborate some more on your images of growth that don't consume more energy, I'd find it helpful to understand this whole thing better.

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