According to the laws of physics, a planet the shape of a donut, or toroid, could actually exist — but it's extremely unlikely to ever form naturally. But what if an advanced alien civilization decided to build one? What properties would a toroid-Earth exhibit? And what would life be like?
One question that came up when I published my Double Earth analysis was "What about a toroidal Earth?" This is by no means a new question, and there has been some lengthy discussions online and earlier modelling. But being a do-it-yourself person I decided to try to analyze it on my own.