This particular question:
I voted to reopen. (Although, at the time it was closed, I was in agreement.)
In its current state, it's a reasonable enough question, essentially asking In order for quantum indeterminacy to be compatible with Islamic beliefs, must we believe in a hidden variable?
However, it wouldn't hurt to define in the question what those terms ("quantum indeterminacy" and "hidden variable") mean.
There's a misunderstanding in the question (the idea that people are somehow required to believe in mathematical models of physical properties), which you address in the new addition to your answer. Over at math.SE, we came to the conclusion that questions which indicate misunderstanding were fine---the answers can correct the misunderstanding.
Narrow fields being off topic:
I would think this would be best addressed case by case. I don't think this is sufficient alone to justify closure.
I don't think this question was closed because it was about a narrow topic. It started off as completely unresearched, and was attracting poor answers (in my opinion).
(Nor do I think of quantum mechanics as a narrow topic.)
On other StackExchange sites, moderators can close questions unilaterally without it being a big problem---if the community is strongly against it, someone votes to reopen, and it enters the review queue where it gets further reopen votes, and gets reopened.
Here, people don't upvote as much, so there are few users who can cast reopen votes (requiring 500 points during beta [158 users currently, if I counted correctly]) and access the review queue (requiring 350 points during beta). This stymies our ability to self moderate, and diamond moderators are forced to make on-the-fly unilateral judgement calls.
Don't like it? Then upvote good questions and answers.
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