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Physics > Economics The Do The Math blog by Caltech-trained UCSD astrophysicist Tom Murphy is the best resource in this area. In particular the posts - Galac

by spodek 7y ago

Physics > Economics The Do The Math blog by Caltech-trained UCSD astrophysicist Tom Murphy is the best resource in this area. In particular the posts - Galactic Scale Energy https://dothemath.ucsd.edu/2011/07/galactic-scale-energy https://dothemath.ucsd.edu/2011/07/galactic-scale-energy - Can Economic Growth Last? https://dothemath.ucsd.edu/2011/07/can-economic-growth-last https://dothemath.ucsd.edu/2011/07/can-economic-growth-last - The dinner conversation with an economist on this topic https://dothemath.ucsd.edu/2012/04/economist-meets-physicist https://dothemath.ucsd.edu/2012/04/economist-meets-physicist

nostrademons 7y ago
I read those and conclude "Physics is not a particularly relevant constraint on economic growth." His energy analysis concluded that at 2.3% growth rate and current technology, we would need to use the entire energy supply falling upon the earth's surface within 275 years. Improving technology might be able to stretch that to 400 years. Within 1400 years, we would need to use the entire energy of our solar system. But we have a number of more pressing demographic constraints. As countries develop, fertility falls; fertility rates are currently below replacement in the entire developed world [1] with all regions other than Africa falling below replacement rate by 2050. Within 80 years, population is likely to start falling, with some studies predicting this within 30 years. Worse, there's a worldwide demographic bulge of 18-30 year old males that's hitting just about now; such demographics have been associated with a higher likelihood of war in the past. There's plenty of other problems that these bring: if you don't get killed in war and manage to find a mate, you're not likely to see your social security or 401(k) worth all that much, nor will you find health care unless your rich or lucky or both. But they'll happen way before we reach physical limits on growth. Our threat model should be stupid politicians doing stupid things at the behest of frustrated populations, not the laws of physics. [1] http://worldpopulationreview.com/countries/total-fertility-rate/ http://worldpopulationreview.com/countries/total-fertility-r...
- freeflight 7y ago
  The demographics issue makes this whole situation such a massive paradox. On one hand, we want all those extra humans to generate "economic growth" to keep our perpetual growth train going. On the other hand, the environmental consequences of that seem already unbearable for our biome right now. It's like we want to have our cake and eat it too, it just won't work. If we want to "save the planet" then we need to let go of this insane idea of perpetual economic growth we supposedly only can solve by throwing more human bodies at it.
  - spodek 7y ago
    Many human cultures have lived without growth. Economists and others who think growth is necessary to distribute goods don't know what they're talking about or have ulterior motives.

by spodek 7y ago

nostrademons 7y ago

I read those and conclude "Physics is not a particularly relevant constraint on economic growth." His energy analysis concluded that at 2.3% growth rate and current technology, we would need to use the entire energy supply falling upon the earth's surface within 275 years. Improving technology might be able to stretch that to 400 years. Within 1400 years, we would need to use the entire energy of our solar system. But we have a number of more pressing demographic constraints. As countries develop, fertility falls; fertility rates are currently below replacement in the entire developed world [1] with all regions other than Africa falling below replacement rate by 2050. Within 80 years, population is likely to start falling, with some studies predicting this within 30 years. Worse, there's a worldwide demographic bulge of 18-30 year old males that's hitting just about now; such demographics have been associated with a higher likelihood of war in the past. There's plenty of other problems that these bring: if you don't get killed in war and manage to find a mate, you're not likely to see your social security or 401(k) worth all that much, nor will you find health care unless your rich or lucky or both. But they'll happen way before we reach physical limits on growth. Our threat model should be stupid politicians doing stupid things at the behest of frustrated populations, not the laws of physics. [1] http://worldpopulationreview.com/countries/total-fertility-rate/ http://worldpopulationreview.com/countries/total-fertility-r...

freeflight 7y ago
The demographics issue makes this whole situation such a massive paradox. On one hand, we want all those extra humans to generate "economic growth" to keep our perpetual growth train going. On the other hand, the environmental consequences of that seem already unbearable for our biome right now. It's like we want to have our cake and eat it too, it just won't work. If we want to "save the planet" then we need to let go of this insane idea of perpetual economic growth we supposedly only can solve by throwing more human bodies at it.
- spodek 7y ago
  Many human cultures have lived without growth. Economists and others who think growth is necessary to distribute goods don't know what they're talking about or have ulterior motives.