I read the study. It's from the same uni I did my Masters in Astrophysics at.

It was a purely mathematical hypothesis paper.
There is no evidence of close time curves being any more real than multiversal theory. The publication is a mathematical approach to if Einstein-Rosen Bridges actually exist within the physical world.

If a CTC is physically proven to exist, then yes, this study has some merit. But as far as current human knowledge goes, this is on the same wavelength as string theory, multiverse theory, or the death of the universe.

You aren't making a lot of sense with your question but the link you posted above refers simply to special relativity

But you'll want into what we astrophysicists call "light cones" or "null cones". This will help point you in the direction that UQ student went with his study on chaos-free time travel. This study also assumes closed time curves, which is still just a hypothesis at this point