1 is going to take a bunch of guesswork to estimate. Assuming it were possible to migrate to the US and live at $200/mo for example, how many people worldwide will be willing to accept that trade? You can run a survey or small scale experiment at best.
What can be done is expand cities to the point where no more new residents want to come in. You can expand the city in stages.
I don’t think the US wants to triple the population with immigrants, and $200/month would require a massive subsidy. (Internet says $1557/month average rent in US)
How many people would you have to get in your city to justify the progress?
100 Million would only be half an order of magnitude larger than Tokyo, and you’re unlikely to get enough people to fill it in the US (at nearly a third of the population, you’d need to take a lot of population from other cities)
How much do you have to subsidize living costs, and how much are you willing to subsidize?
If I understand correctly it is possible to find $300/mo/bedroom accommodation in rural US today, and a large enough city will compress city rents down to rural rents. A govt willing to pursue a plan as interesting as this one may also be able to increase immigrant labour to build the houses and relax housing regulations. US residential rents are artificially high compared to global average. (In some parts of the world, a few steel sheets (4 walls + roof) is sufficient to count as a house, even water and sewage piping in every house is not mandatory as long as residents can access toilets and water supply within walking distance.)
(A gigacity could also increase rents because it’ll increase the incomes of even its lowest income members. But yeah in general now you need to track median incomes of 1B people to find out new equilibrium.)
1 is going to take a bunch of guesswork to estimate. Assuming it were possible to migrate to the US and live at $200/mo for example, how many people worldwide will be willing to accept that trade? You can run a survey or small scale experiment at best.
What can be done is expand cities to the point where no more new residents want to come in. You can expand the city in stages.
Definitely an interesting survey to run.
I don’t think the US wants to triple the population with immigrants, and $200/month would require a massive subsidy. (Internet says $1557/month average rent in US)
How many people would you have to get in your city to justify the progress?
100 Million would only be half an order of magnitude larger than Tokyo, and you’re unlikely to get enough people to fill it in the US (at nearly a third of the population, you’d need to take a lot of population from other cities)
How much do you have to subsidize living costs, and how much are you willing to subsidize?
If I understand correctly it is possible to find $300/mo/bedroom accommodation in rural US today, and a large enough city will compress city rents down to rural rents. A govt willing to pursue a plan as interesting as this one may also be able to increase immigrant labour to build the houses and relax housing regulations. US residential rents are artificially high compared to global average. (In some parts of the world, a few steel sheets (4 walls + roof) is sufficient to count as a house, even water and sewage piping in every house is not mandatory as long as residents can access toilets and water supply within walking distance.)
(A gigacity could also increase rents because it’ll increase the incomes of even its lowest income members. But yeah in general now you need to track median incomes of 1B people to find out new equilibrium.)