So I asked the question "Can one construct a non-zero (conditional) probability in this situation?", which was downvoted and voted to close without the last edits (so I deleted it - The original tag was quantum information). Is it welcome to this stack exchange after the edit?
First of all, there is no reason to delete a question and then ask it again with only minor changes, you can just edit the original question.
Regarding the question itself, I do agree with the voters that it's not very clear what is been asked. I don't know that it should be closed by it's borderline there. The wording is in general vague and unspecific. For example, you say
What one "sees" is an eigenvalue linked to that of a photon.
which might be interpreted in different ways. What photon are you talking about? What do you mean by "see" here? Where did eigenvalues come from in this discussion? Or
With each eigenvalue one can determine there is some "source"
what is a "source"? Where did you get this statement from? etc.
There might be some merit in the question you maybe meant to ask, but it's not easy to get to it. In general, I would try to avoid using concepts that you cannot properly define and try to formulate things mathematically as well as in words, when possible. Finally, a good rule of thumb is that if you cannot give a very good idea of the question being asked in the title of the question itself, that is a good indication that it's not going to be a good question. There are exceptions, but it usually works pretty well (and note that from the title of your question, I would have no idea what is actually being asked).