>>121821591. As other commenters have noted, it doesn't matter about the positive curvature if that's all the inhabitants have ever known.
2. There can't be any windows because then the inhabitants would look out and start to ask generative questions (i.e., questions that lead to more questions that would eventually lead to them discovering the nature of their world) about what they see.
3. If there are no windows then you have to have a light source such as LED panels but that also would cause the inhabitants to ask generative questions whether or not they could get close to them.
4. A Foucault Pendulum would, as on Earth, demonstrate the rotation of their world but then some Galileo type would look at that result and note the similarity of their world to a bucket swung around on the end of a rope and devize a theory of its "gravity."
5. Then a Coriolis type would notice that objects dropped from a great height would not fall straight down but would follow a curved trajectory, which would confirm the whirling bucket theory of the Galileo type.
6. Finally a Columbus type would get enough money from his king to mount an expedition to the opposite side by drilling a hole to the outside in order to bypass all the savage tribes between them and the spice lands on the opposite side. But as soon as he succeeds in drilling the hole, the airt is lost and that's the end of them all.
