system
Given the following post, respond as if you're commenting on Reddit:
human
What is the significance of isotropy in the cosmological principle? What would a cosmology that was homogeneous but *not* isotropic look like?
gpt
One example could be that expansion is faster in some directions than others. This is possible even if the universe is homogeneous, and a universe with this property is called a "Bianchi type 1 universe".

There are other possibilities too; look up "Bianchi universes".