I asked a question about black holes that already had an answer on the Physics Stack Exchange. This has raised quite some discussion in the comments, as to how questions that are on-topic for several sites should be addressed.
Should they be closed with a link to the other site? (Need an additional mechanism to enable this, though)
Should it be migrated to physics?
Something else?
How do we deal with questions that are on topic for more than one site?
If the question is on topic here and is not copy/pasted from another site, then it should remain open here. Answers may reference the answers on other site(s) if they want.
If you have not yet asked a certain question and it is on topic on more than one site, you get to pick which site you would like to tailor it to. In a handful of cases, it may be appropriate to tailor it to more than one site--as long as you're not just copy-pasting it shouldn't get closed for cross-site posting.
