Our universe apparently has three spatial dimensions, so if it were donut shaped it would have to be a 3-torus, which is beyond my ability to visualize as its enclosed volume is some kind of hyperdonut in four dimensional space. But what the physical implications of the universe being a 3-donut, and can we look for them?
Source: wiktionary
An eight-dimensional hyperdonut is complicated enough to let me hand-wave concerns for sensibility.
Source: wiktionary
You’re unable to manage the mess of hyperdonuts and find yourself lost in hyperspace!
Source: wiktionary
What does all this mean in practice? Well, we don’t expect our quantum processors to look like hyperdonuts.
Source: wiktionary