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Exponential Economist Meets Finite Physicist (2012)

dothemath.ucsd.edu

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Re: Exponential Economist Meets Finite Physicist (2012)

#71

Post by sonnyblarney »

age_bronze wrote: post #30

There's an underlying assumption that economical growth has anything to do with physical limits. Economical growth is a lie we tell ourselves so that innovation has its incentives, while everything else that's there because it must be there (because it will always have a demand), such as energy (but also food, real estate, etc.) just piggybacks with a similar 'fake growth' that really arises only from the fact these…

So a cure for a disease is just some 'big economic lie'?

You started off right (i.e. it's not about material limits) but then I think you missed that material value can be created out of thin air.

As long as humans are innovating and improving their conditions, then 'growth' as we understand it continues.

The iPhone is not 'great' because of the amount of physical material we put into it.

The numbers we put growth it are a function of other, relative things, but the fact remains that value is being created.

Re: Exponential Economist Meets Finite Physicist (2012)

#72

Post by cinquemb »

jbay808 wrote: post #64
jeremysalwen wrote: post #62

I read through the comments expecting the typical HN takedown of the whole bogus idea that energy must become cheaper as a fraction of the economy in order for it to keep growing. But surprisingly, nobody more economically literate than me has done so, so I guess it falls on me. We already have experience with an economic input which is required for practically all production becoming less important to the economy as…

I'm not sure this is quite a takedown of the author's point. In fact, I'm surprised at how many people on HN seem to be misunderstanding this. The author is saying that physics puts a fairly solid cap on the amount of power we can produce on earth. That's the basic point. What does a finite energy-consuming, exponentially growing economy look like? If we accept that all economic transactions consume some energy, and…

>then once we've hit our physical constraint on power generation

Are we supposed to accept this? Because I do not. I think the way that we allocate resources towards energy collection/generation/consumption is a bigger constraint than what physics can currently allow.

Re: Exponential Economist Meets Finite Physicist (2012)

#73

Post by b_tterc_p »

jbay808 wrote: post #15
b_tterc_p wrote: post #12

Earlier quoted context omitted.

The price of energy is capped at the cost to privately produce it for yourself, which is probably pretty low in the scheme of all encompassing virtual real estate fiscal gods.

Not unless the physical economy is growing at about the same rate as the virtual one. Or else how is that extra power generation capacity being added?

If the virtual economy grows 10%, that doesn’t mean we need 10% more energy to make it happen.

Re: Exponential Economist Meets Finite Physicist (2012)

#74

Post by paraschopra »

ThrustVectoring wrote: post #49
age_bronze wrote: post #30

There's an underlying assumption that economical growth has anything to do with physical limits. Economical growth is a lie we tell ourselves so that innovation has its incentives, while everything else that's there because it must be there (because it will always have a demand), such as energy (but also food, real estate, etc.) just piggybacks with a similar 'fake growth' that really arises only from the fact these…

The less cynical interpretation is that "real goods and services" captures the value people derive from them , rather than some objective measure like "energy consumption". There's no innate reason why we can't figure out more and more valuable ways to do things pretty much indefinitely.

It depends what you call and measure as value.

If it’s production or goods, there’s obviously an upper limit. Even if in distant future, we begin assembling atoms into making novel rare elements, all that process consumes energy and possibly would produce waste. Production is not free. In the exponential limit, we will hit some constraint.

If we are talking about services, we should realise that even they cost energy. Even if we tomorrow think that long distance travel will be replaced by VR, production and delivery of such experiences cost energy.

Fundamental argument is then about energy. Can we keep harnessing it infinitely? No. Even if we make energy efficient processes, Jevon’s paradox suggests we will simply start using more energy.

The only way physical limits can be respected is by limiting the growth of economy and population. (Otherwise if we keep printing money without increase in production, it isn’t really economic growth)

Re: Exponential Economist Meets Finite Physicist (2012)

#75

Post by fallingfrog »

bshipp wrote: post #70
ThrustVectoring wrote: post #49

Earlier quoted context omitted.

The less cynical interpretation is that "real goods and services" captures the value people derive from them , rather than some objective measure like "energy consumption". There's no innate reason why we can't figure out more and more valuable ways to do things pretty much indefinitely.

Indeed. Take a look at cars, for example. My little 2.0L engine makes more power than a 1970's V8 behemoth could have dreamt of, while simultaneously getting fantastic fuel mileage with minimal pollutants (in comparison). It's by no means perfect, but by any objective measure it's providing me with more value at a lower energy cost. Energy cost to operate, energy cost to build, energy cost to maintain. And that trend…

There is a physical limit to the efficiency of a heat engine though. If your powertrain is 25% efficient, you can double it to 50%. But if it's 50%, you cannot double it to 100% unless the engine is operating at a temperature of absolute zero. You're going to reach a point- and current model cars are probably just about there- where the engine is operating about as efficiently as the laws of physics permit, and then you're not going to make further progress. Just google "Carnot cycle" and you can learn more.

Re: Exponential Economist Meets Finite Physicist (2012)

#76

Post by fallingfrog »

ThrustVectoring wrote: post #49
age_bronze wrote: post #30

There's an underlying assumption that economical growth has anything to do with physical limits. Economical growth is a lie we tell ourselves so that innovation has its incentives, while everything else that's there because it must be there (because it will always have a demand), such as energy (but also food, real estate, etc.) just piggybacks with a similar 'fake growth' that really arises only from the fact these…

The less cynical interpretation is that "real goods and services" captures the value people derive from them , rather than some objective measure like "energy consumption". There's no innate reason why we can't figure out more and more valuable ways to do things pretty much indefinitely.

If by "pretty much indefinitely" you mean "one or two human lifetimes", then sure. Our horizons are so compact these days. Certainly not for thousands of years, running the math gives absurd results for any growth rate.

Re: Exponential Economist Meets Finite Physicist (2012)

#77

Post by drdeca »

lutorm wrote: post #42
age_bronze wrote: post #30

There's an underlying assumption that economical growth has anything to do with physical limits. Economical growth is a lie we tell ourselves so that innovation has its incentives, while everything else that's there because it must be there (because it will always have a demand), such as energy (but also food, real estate, etc.) just piggybacks with a similar 'fake growth' that really arises only from the fact these…

Yeah, as far as I understand, there's nothing preventing you and me just trading the same money back and forth at ever increasing speed, creating economic "growth" without physical limits.

There are physical limits on how fast you can do that.

Bremermann's limit, (or some extension of it?), says that the minimum amount of time needed for a system with average energy E to change to an orthogonal state, is inversely proportional to E (specifically, pi * h_bar, all divided by 2E ).

So, assuming that “I have the money” and “you have the money” are orthogonal (collections of) states, then there is a maximum rate at which the system can switch between those states.

You might say “well, what if we just count the number of transactions that ‘should’ have happened, instead of counting the number of actual events where the money changes hands”, but that seems to obviously not reflect actual benefit?

If me and another person turn away from you, and then turn back, and claim that we exchanged ownership of a dollar bill I’m holding 2^64 times while we were facing away from you, the obvious response would be “no, you didn’t.”.

Re: Exponential Economist Meets Finite Physicist (2012)

#78

Post by drdeca »

jasonhansel wrote: post #66

Even if there is some limit to economic growth in the distant future, is that necessarily a bad thing? It might be that, by the time we reach this limit, society would be so prosperous that we would see no reason to exceed it.

This seems possible, yes, though if it is the case, I think we ought to prepare for that eventuality somewhat ahead of time, so that we don’t encounter a nasty shock when the time comes.

Re: Exponential Economist Meets Finite Physicist (2012)

#79

Post by cinquemb »

paraschopra wrote: post #74
ThrustVectoring wrote: post #49

Earlier quoted context omitted.

The less cynical interpretation is that "real goods and services" captures the value people derive from them , rather than some objective measure like "energy consumption". There's no innate reason why we can't figure out more and more valuable ways to do things pretty much indefinitely.

It depends what you call and measure as value. If it’s production or goods, there’s obviously an upper limit. Even if in distant future, we begin assembling atoms into making novel rare elements, all that process consumes energy and possibly would produce waste. Production is not free. In the exponential limit, we will hit some constraint. If we are talking about services, we should realise that even they cost energy…

> Fundamental argument is then about energy. Can we keep harnessing it infinitely? No. Even if we make energy efficient processes, Jevon’s paradox suggests we will simply start using more energy.

The thing about infinity is that while it is a limit, it can always be approached based on ones understanding. And I would not state that our knowledge and application of energy collection/generation (and even energy itself) is fairly limited.

>The only way physical limits can be respected is by limiting the growth of economy and population. (Otherwise if we keep printing money without increase in production, it isn’t really economic growth)

I disagree (and debt monetization != printing money), naturally markets and systems will correct. They always have, even when people try to distort it and keep them from correcting.

Re: Exponential Economist Meets Finite Physicist (2012)

#80

Post by drdeca »

cerealbad wrote: post #36

isn't the universe expanding at an accelerating rate? if the problem is excess planetary heat, you can use thermosynthesis to accelerate novel thermogenesis in pseudo-living species - imagine endothermic sea sponges cooling the oceans and helping to repopulate at risk ocean animals. "this thing humans do cannot continue" is a weak argument. everything humans do is some expression of the natural state of conditions in…

> if the problem is excess planetary heat, you can use thermosynthesis to accelerate novel thermogenesis in pseudo-living species - imagine endothermic sea sponges cooling the oceans

Uh,

Thermodynamics.

You can’t destroy heat, just pump it around.

A heater does not need to expel cold. A cooler needs to expel heat.

Stuff can feed on heat gradients. Things cannot feed on uniform heat.

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