Originally posted by: AcidBath
Assuming the sun was to just "go out" and not die in normal fashion, in which case the Earth would be roasted by a rapidly expanding sun before we even have to worry about being cold, and also assuming humans could survive, the earth would eventually cool to about 2.7 Kelvin (or about 270 degrees below zero). Being just a few degrees above absolute zero nothing would survive. The entire plant would freeze to the core. Our atmosphere would be gone. We would be unprotected from high amounts of solar radiation that would assail our plant. Of course oxygen would be a thing of the past. So while we can create "artificial sunlight" quite easily life would end without the real thing.
But if you insist it would be great without the sun just take a trip to northern Siberia during a six month night and let us know how it goes.