(Social influence might not be the best word here.)
1) rewarding creativity (its opposite might be more infamous)
a) Convening for idea generation, esp. regularly on a schedule (Purpose, Method)
b) via joining hallways and close proximity. (Method for increasing Creativity/Productivity)
Examples that come to mind:
People in the same/similar fields can achieve more working together. People in different fields working together can as well, both for similar reasons (2 heads > 1, identical shared problems) and different ones (seeing if stuff from one domain is useful in another instead of overlapping competency protecting against errors).
 /talking with each other
 Some ‘fields’ might be better (off) than others if they manage to solve basic issues better—more widespread use of better teaching/learning methods, distilling more (and having less ‘research debt’) or being better at coming up with explanations that are easier to understand, being better at encouraging/enabling collaboration, etc.
 See this post; it’s rather empirical, and goes fairly in depth: https://www.lesswrong.com/posts/f2GF3q6fgyx8TqZcn/literature-review-distributed-teams.
relying on co-location over processes for information sharing is similar to relying on human memory over writing things down: much cheaper until it hits a sharp cliff. Empirically that cliff is about 30 meters, or one hallway. After that, process shines.