I see a thermodynamics corollary there. The overall "temperature" in an area is the mean income of an area. Colder is poorer. You may be able to apply some hea

I see a thermodynamics corollary there. The overall "temperature" in an area is the mean income of an area. Colder is poorer. You may be able to apply some heat here and there, but any source of heat (money) is drained and attempts to balance out with the ambient cold temperature. And given the expanse of a cold mass, a localized heat source is nary enough to raise the ambient temp by fractions of a degree. This cold temp is what we would call a blight or distressed neighborhood. The way to fix this is to raise the temperature everywhere by broad injects of money/goods/services.