Graduate Does anyone know asymmetric dynamic global solutions to Einstein eqs?

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The discussion centers on the search for asymmetric dynamic global solutions to Einstein's equations in general relativity. Participants highlight the historical challenges in proving existence theorems, noting that most advancements have focused on small perturbations of symmetric solutions. There is a call for research that addresses more realistic physical configurations, with some contention over what constitutes "realistic." A mention of a 1969 result by Choquet-Bruhat and Geroch indicates that global existence has been established, but understanding of these solutions remains limited. The conversation emphasizes the need for clarity and relevance in addressing complex topics in physics.
Heikki Tuuri
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https://link.springer.com/article/10.12942/lrr-2005-6

https://en.wikipedia.org/wiki/Exact_solutions_in_general_relativity

http://www.numdam.org/article/SEDP_1989-1990____A15_0.pdf

A moderator removed this off-topic discussion from another thread. Does anyone on the Physics Forums have expertise on the existence of global solutions of general relativity?

As you see, people have worked very hard for 104 years to prove existence theorems. As far as I know, they are all limited to small perturbations of highly symmetric solutions.

Can anyone point to research that might have progressed closer to realistic physical configurations?
 
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Heikki Tuuri said:
Can anyone point to research that might have progressed closer to realistic physical configurations?
Part of the problem (the main problem) was your personal and overly restrictive view of what constituted a realistic physical configuration. For example, you objected to the FLRW solution as being unrealistic whereas most scientists and particularly cosmologists consider it realistic.
 
Heikki Tuuri said:
As you see, people have worked very hard for 104 years to prove existence theorems. As far as I know, they are all limited to small perturbations of highly symmetric solutions.
That is not true. Global existence (as in the maximal hyperbolic Cauchy development) is a result from 1969 (Choquet-Bruhat, Geroch). What is limited is the understanding of those solutions.
Can anyone point to research that might have progressed closer to realistic physical configurations?
What do you mean by realistic physical configuration?
 
Heikki Tuuri said:
A moderator removed this off-topic discussion from another thread.

Which is completely irrelevant to this thread. Please do not carry over whatever issue you might have with the moderators in a previous thread to new threads.
 
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