Hi Bruce,
Well. That is a pretty interesting theory. I have one serious question. What happens if the lines don’t cross at π? That would mean that looking a different direction allowed one to see only one quarter of the stars. So what? May be πi is where the Big Bang is. It might look like the drawing of yours that I altered:
π

It certainly is less complicated and rotates well, but there appears to be half the universe forever unseen. I don’t know what that means.
Several discs is an interesting way to solve the many-layers problem. As you say, it’s the only way with your model. It is hard for me to conceptualize in the three-dimensions- plus-one model. The one-dimension-plus one model we’ve been discussing can be thought of as a pipe with defined layers. The extension to two more dimensions is mind-boggling. However, I can see that such a shape can exist in five dimensions. However, it seems to me that expansion rate of each universe would have to be the same, while speed of light was different. On the other hand deviations from this might not be noticeable within the small volume of a galaxy. All I can say is that effective faster-than-light travel by shifting layers works for us.
By the way, Artemy and my sister should be back soon. I’ll see what they think of your model. Artemy would actually like to visit you, forbidden as it is. I think Lem is the oly one who can stop her.
So until next time, maybe after Artemy and my sister are back.
Sallys