Exponential Economist Meets Finite Physicist (2012) • Hacker News Board

Re: Exponential Economist Meets Finite Physicist (2012)

#171

Post by sadness2 » Mon, Jun 03, 2019, 2:52 PM UTC

mac01021 wrote: post #134

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…

Is that true? My physics is admittedly not great. However I though a 100% efficient lightbulb generates just as much heat, but at the place where the photons land (walls, floor, etc) rather than at the bulb. I think basically any time we use energy, whether by running current through a lightbulb it by respiration after eating food, it ultimately ends up as heat.

The energy we use starts out as kinetic (wind, water), or heat (solar, thermal), or chemical, etc. We then use and it get it to do work, which in most cases converts much of it back into kinetic energy, and where there is inefficiency, heat, but even that part can end up in sinks which can find themselves ultimately back in places where heat already resided.

Re: Exponential Economist Meets Finite Physicist (2012)

#172

Post by orasis » Tue, Jun 04, 2019, 1:12 AM UTC

kreldjarn wrote: post #3

orasis wrote: post #2

Exponential growth can continue in virtual realities as the physical reality maxes out.

Did you read the piece? They talk about VR.

1 additional bit of information allows exponentially more complexity to exist. Digital scales very very well.

Re: Exponential Economist Meets Finite Physicist (2012)

#173

Post by jeremysalwen » Wed, Jun 05, 2019, 4:13 AM UTC

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…

Again, we already have experience with a finite labor-consuming exponentially growing economy looks like. I don't know how this comment is a rebuttal, since it doesn't address any of the points I made.

Especially since it repeats a line of reasoning, whose premises clearly apply to labor, but whose conclusions are clearly incorrect in the case of labor.

"So the price of energy must continue to drop" simply does not logically entail from the preceding premises.

Re: Exponential Economist Meets Finite Physicist (2012)

#174

Post by mac01021 » Sat, Jun 08, 2019, 2:19 AM UTC

sadness2 wrote: post #171

mac01021 wrote: post #134

Earlier quoted context omitted.

Is that true? My physics is admittedly not great. However I though a 100% efficient lightbulb generates just as much heat, but at the place where the photons land (walls, floor, etc) rather than at the bulb. I think basically any time we use energy, whether by running current through a lightbulb it by respiration after eating food, it ultimately ends up as heat.

The energy we use starts out as kinetic (wind, water), or heat (solar, thermal), or chemical, etc. We then use and it get it to do work, which in most cases converts much of it back into kinetic energy, and where there is inefficiency, heat, but even that part can end up in sinks which can find themselves ultimately back in places where heat already resided.

> which in most cases converts much of it back into kinetic energy

Are you thinking of transportation here? We burn fuel to add kinetic energy to a car or airplane but, by the time the vehicle has stopped moving, all of that energy has been converted into diffuse heat in the wheels, brake pads, atmosphere, etc, never to be harnessed again for the mostpart.