Actually in 2d they are but there are other problems in 2D. There are actually quite a few special properties of 3D+1 interesting reading https://en.m.wikipedi

Actually in 2d they are but there are other problems in 2D. There are actually quite a few special properties of 3D+1 interesting reading https://en.m.wikipedia.org/wiki/Anthropic_principle#Dimensions_of_spacetime https://en.m.wikipedia.org/wiki/Anthropic_principle#Dimensio...