And... the people? Where do they come from? Mars?

All you're describing is population redistribution, not population creation. Urban centers have very low fertility rates, which actually reduces populations...

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t-3 7 hours ago | parent [-]

Yes, the people come from other places. The "population center" is very often made by people with intention though. The global population is still rising, so conjecture about the effect of cities on fertility rates is irrelevant. Humans aren't going extinct any time soon.

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oblio 6 hours ago | parent [-]

Did you read my previous comment in detail?

People don't live in caves, they will create light pollution everywhere, anyway. Might as well put them in small and dense population centers.

I hate reading comprehension these days :-)

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t-3 6 hours ago | parent [-]

You said: "Nobody "creates" population centers."

That's demonstrably false, population centers are created all the time. The fact that populations don't spontaneously appear is irrelevant.

	▲	oblio 4 hours ago \| parent [-]
		I said a lot more than that and this entire discussion is in the context of high speed trains and light pollution. Again, reading comprehension, context, and I guess, typical techie obtuseness.