Discuss why the article says the fact that we’re in our universe complicates our understanding of the expansion of the universe.
Explain the significance behind the universe having a flat geometry.
Discuss how gravity impacts how galaxies behave when they get close to one another.
this is the article: https://www.npr.org/sections/13.7/2017/05/24/529675773/what-does-an-expanding-universe-really-mean
