You said that moving people like that [Cognitive Shadows] or spren off-world, from Roshar is difficult.
What about physically, say the Ones Above visit them, and they fly away?
So one of the things you'll have to be asking questions and theorizing on is what happens if you try to carry a spren around the planet. What happens to their Cognitive sense, right? So you're on Roshar, right? So on the Physical Realm what would happen-- Because on Shadesmar, you have a flattened version. So there are questions for you to be theorizing implicit in that. And one of them is, what happens, you cross a threshold circling the globe, your spren, what happens to them? Because-- Okay? This relates to the question you’re asking.
Wait wait, you have a three dimensional plain coexisting with a two dimensional plain?
Well, two dimensional is the wrong term, but basically...
Can you specify the mathematically projection used to create this? *laughter*
We'll try to give it to you eventually, but this is the sort of stuff that I do that Peter's like "Oh man..." *laughter* "Alright give me the math Peter." "Ahhh what do you mean? I'm not a mathematician." "Eh, y'know. You're close." It is very convenient to have a physicist and a mathematician in my writing group.