If the universe had this shape, a traveler who crossed through one of the pentagonal faces would instantly reappear at a face on the opposite side of the dodecahedron.
Weeks and his collaborators were drawn to study the dodecahedron because recent observations of the universe's cosmic microwave background radiation have suggested that the universe either is flat or has slightly positive curvature, such as a sphere does.
The dodecahedron model, however, appears to match data on both the quadrupole and the next-longest wavelength, called the octopole.
Spergel and his collaborators examined whether the dodecahedron satisfies a criterion called the circle test.
If the bubble were much smaller than the dodecahedron, we would see nothing of the pentagonal faces.
Weeks agrees that the absence of matching circles would kill the dodecahedron model.
It's not clear whether the 1-percent-error estimate would carry over to the dodecahedron, Weeks says.
However, he does not expect the simulations to validate the dodecahedron model.