As I'm not learning quantum mechanics formally in a classroom, I have no real experience with the matter, or a teacher to whom I can pose my questions. There are a few experiments I'd like to run as well, but no way to do so. In any case, I'm hoping that someone else has run these experiments, or at least has theories as to what will happen. What happens if you run the double slit experiment, recording which particles go through which slit, look at the back wall before looking at the results of the observations, then look back at the wall? Will it start off as an interference pattern, then become a clumping pattern, since your knowledge about the particles has changed? Will it "predict" that you will look at the data, and start off as a clumping pattern? Will the fact that you've already looked at the wall lock the particles in place, so even after you look at the data, their positions won't change because you know where they landed? Or something completely different? What happens if you run the experiment with two (groups of) people, one to look at the wall and one who may or may not look at the data. Will the results always agree with each other? Does it matter if you look at the wall or the data first, even if it's two different people doing so? Thank you for reading, and hopefully for responding.