Are closed time like curves an inherent feature of rotating universe models?

[Galteeth]

This is a follow up to my previous question, as they appear that in both the Godel Metric and the Van Stockum dust

Perhaps a better way to put this is, could there be a model where you had rotation (maybe around a non-symmetrical axis?) and not get these CTCs?

 

[JesseM]

On this old page by a guy who did his PhD thesis on rotating universes in GR, in the section "Time Traveling and Rotation of the Universes" he writes:

The rotation of the universe, i.e., the vorticity, is a local property. The closed time-like curve is a global feature. Accordingly the connection may be obscure. We don't have any concept of a universe rotating as a whole: The picture is complicated very much by the non-existence of a suitable global reference system; by the presence of shear and expansion; by the space-time curvature; and by the infinity of the universe.

There are rotating universes that do preserve causality. I am not aware of any non-rotating universe that violates causality.

He doesn't elaborate on that statement though (his name is Egils Sviestins, and http://www.isif.org/fusion07CD/Fusion07/pdfs/Fusion2007_1143.pdf seems to give an email for someone of that name, you could try contacting him). Also, in the later section "Is Time Traveling Possible in our Universe?" he writes:

In order to be able to travel to the past, three conditions should be fulfilled:

1. Einstein's General Relativity is a valid description of the universe.
2. The Universe has a suitable structure probably incorporating sufficiently fast rotation.
3. The practical difficulties can be overcome.

So it may have something to do with the rate of rotation, but the previous quote suggests that the exact connection between the type of rotation and the possibility of CTCs isn't easy to state.