What are some open questions in general relativity for microscopic objects?

[Dmitry67]

I wanted to check with you a list of open, unresolved questions in GR. It is well known that GR is not compatible with QM, so obviously there are many unsolved mysteries on the QM level. However, here I wanted to focus exclusively on a small subset of questions:

not related to QM, LQG, superstring etc. So we are talking about microscopic objects with energies << plank scale and spacetime curvature >> plank scale. It is an area where GR should explain everything (with some precision).

Here is my list. Please let me know if something can be removed from it. Or added.

1. What GR version is true: classical or Eistein-Cartran.
2. Can a superextreme BH be formed, naturally or artificially? (cosmic censorship hypotesis)
2a. What happens if kerr singularity becomes naked and observers can enter closed time-like loops?
3. Can observers pass thru the "blue sheet" unharmed?
4. How stable is the Kerr solution in case of a real black hole, so if it contains hot gas, emiting light, particles, hitting the "blue sheet"/Cauchy horizon forming there infinite density?
5. What happens if we go thru the kerr ring?

Let me know if you know any answers. I asked some of these questions before but nobody replied...

 

[Demystifier]

1. At the moment, there are no experiments that could distinguish between pure Einstein and Einstein-Cartan theory. From the theoretical point of view, various attempts to formulate more fundamental theories involve supergravity, which suggests that Einstein-Cartan could be more correct than pure Einstein.

 

[stevebd1]

You might find some of the points raised in this thread of interest-

https://www.physicsforums.com/showthread.php?t=144800

and regarding CTC's-

https://www.physicsforums.com/showthread.php?t=249107