Geons in Geometrodynamics: J.A. Wheeler & Stability Questions

[Markus Hanke]

J.A. Wheeler has in the 1950s investigated topological constructs called geons, which are essentially gravitational wave packets held together by their own field energy. I have two questions with regards to this :

1. Is there a consensus yet on whether geons in classical GR ( torsion vanishes everywhere ) are stable or not ?
2. Does anyone know whether it has been investigated whether such geons could exist in a space-time endowed with a connection other than the Levi-Civita connection of GR, e.g. with a Weizenboeck connection, or some other connection "mixing" curvature and torsion ? Is there a possibility they could be stable, then ?

I'd just like to know as a matter of personal interest.

Thank you in advance.

 

[jedishrfu]

Wikipedia on geons:

http://en.wikipedia.org/wiki/Geon_(physics )

mentions that the LQG people may have an object similar to a geon in their theory.

 

[Markus Hanke]

True, but I was specifically interested in the "original" geon model. The Wikipedia article says that it is still not clear whether they are stable in GR space-time, so I was wondering what the current consensus on this is. This is probably not one of those articles which gets updated regularly.

 

[jedishrfu]

You best bet would be to check the Physics Arxiv to see if there's any papers on the subject. I found one such paper:

http://arxiv.org/abs/1210.1606

 

[sardar]

I am not an expert in the specific research on geons and their stability in different types of connections. However, I can provide some general information and perspectives on this topic.

Regarding the first question, the stability of geons in classical general relativity (GR) is still a topic of ongoing research and there is no consensus yet. Some studies suggest that geons may be unstable due to the presence of gravitational radiation, while others propose mechanisms for stabilizing them. It is a complex and challenging problem, and more research is needed to fully understand the stability of geons in classical GR.

Regarding the second question, there have been some studies on geons in alternative theories of gravity, such as those that include torsion or mix curvature and torsion. Some of these studies suggest that geons may be stable in these theories, while others suggest they may still be unstable. It is an area of active research and there is no definitive answer yet.

Ultimately, the existence and stability of geons in different theories of gravity is an important and intriguing topic, and further research is needed to fully understand them. I hope this helps answer your questions and satisfy your personal interest in this subject.