Allow me to apologize upfront if this is well trodden turf. I've looked over Arioch's Analyst site (Big Props) and I'm not finding too much information on exactly how Culture works in the game.
My mind started sparking when I saw this screen shot.
We can see that this is the city screen, with the Empire Bar above it. A few questions/thoughts.
1) Is it the cities own culture that is responsible for filling the hexagon responsible for border growth, or does the empire culture effect that as well? My assumption is that it is the city that is solely responsible for this growth.
2) When the borders do expand, will it be every pink highlighted hex that expands? There are other screenshots of an earlier game where only one hex is highlighted. Is it possible that as the game goes on cities begin capturing more then one hex at a
3) In the Empire Bar, in pink, are the numbers 36/1315 (+20). It is clear that the 20 is the total collected amount of culture all your cities are giving out a turn. It is also clear that there is 36 of 1315 culture collected. What happens when you collect 1315 culture? Is that the amount of culture required to purchase the next social policy? Does this mean you are essentially "Researching" social policies the way you research technology?
4) Is it possible to spend empire culture to expand a cities borders, or is it only possible to do that with gold? If it is the case that you cannot spend culture to expand borders, then city culture is only passive?
Anyway, there is a few questions there. Let the speculationatroning commence!
My mind started sparking when I saw this screen shot.

We can see that this is the city screen, with the Empire Bar above it. A few questions/thoughts.
1) Is it the cities own culture that is responsible for filling the hexagon responsible for border growth, or does the empire culture effect that as well? My assumption is that it is the city that is solely responsible for this growth.
2) When the borders do expand, will it be every pink highlighted hex that expands? There are other screenshots of an earlier game where only one hex is highlighted. Is it possible that as the game goes on cities begin capturing more then one hex at a
3) In the Empire Bar, in pink, are the numbers 36/1315 (+20). It is clear that the 20 is the total collected amount of culture all your cities are giving out a turn. It is also clear that there is 36 of 1315 culture collected. What happens when you collect 1315 culture? Is that the amount of culture required to purchase the next social policy? Does this mean you are essentially "Researching" social policies the way you research technology?
4) Is it possible to spend empire culture to expand a cities borders, or is it only possible to do that with gold? If it is the case that you cannot spend culture to expand borders, then city culture is only passive?
Anyway, there is a few questions there. Let the speculationatroning commence!