Buses and trains. That, or spaghetti interchange that are bigger than the rest of the city. Also, replace key arterial roads with a pedestrian path, call that path a park, and charge $20 for entry. That will easily fund all the city services and nobody will be too inconvenienced by having to pocket their car as they walk across the “park” to get between neighborhoods. Now excuse me, I have to go murder a little blue bird that won’t shut up about the garbage piling up
If you use the right color of light, then the doppler effect means that the atoms will only absorb (and be pushed by) light that they are headed towards. That means that the light will always act as a brake for the atoms and never an accelerator, so the fluid will cool. If you do this from all directions, the fluid will start to stay still in one place and get very close to absolute zero. Idk, I just read the Wikipedia article, but that is my best attempt at an ELI18