Why is carbon dioxide non-polar every explanation keeps using the symmetry argument but I want to know what is fundamentally cancelling out because as far as I can tell there should be a positive middle without two negatives on the outside?
I read that in developing GR, Einstein's original equation indicated that the universe is expanding and later he quickly dismissed it by adding the cosmological constant. I kept wondering, why did he introduce expansion in the first place? I can understand the importance of cosmological constant ...