Turns Out There Is No Actual Looking Up

Direction is something we humans are pretty accustomed to. Living in our friendly terrestrial environment, we are used to seeing things in term of up and down, left and right, forwards or backwards. And to us, our frame of reference is fixed and doesn't change, unless we move or are in the process of moving. But when it comes to cosmology, things get a little more complicated. For a long time now, cosmologists have held the belief that the universe is homogeneous and isotropic - i.e. fundamental...