Have we figured out of those Elderscrolls are even physical or not? Withouth figuring this out, you can't have a discussion to start with. From the top of my head, and I'll leave this for some one else to source, there are three lines of thought.

The scrolls are simply written.
The scrolls are divine artifacts from X.
The scrolls are not from this world and differ in appearance depending on observer, ect.