^They must reconcile their differences.
Given the positioning of that diagram, it may be related to the book that's lying three feet away from it (presumably the Last Stand is kept in that pile).
The diagram looks vaguely familiar...
It puts me in mind of The Gods Themselves by Asimov. In particular, the idea of fusion and fission reactions releasing less energy in parallel universes with different laws of physics, though in that case it was relevant to stars, not the cores of planets. Basically, the stars in a universe with less strong nuclear force would need be bigger to be stable (i.e. enough energy to maintain fission and fusion). If you drew the stars in a diagram from greatest fission effects to smallest, it would resemble the diagram in the Inn, except without the landmass attached to the glowing portion.
In the Inn, the glowing portion would seem to be the mana core. The text that pops up says:
This looks like the diagram of the birth of a planet.
Mana solidifying into the earth (and other) elements while also conserving, if not mass, volume. It ties into some of the models of magic that have been proposed on the forums previously.