Over here, Spherical suggested it might be interesting to discuss the various interpretations of quantum mechanics. This is a pretty good introduction to the most prevalent, with some explanation of the similarities and differences. So, what's your opinion of the various choices? Is there one that's "obviously" the most reasonable? Should we hold out on making a judgment until someone comes up with a way to distinguish these cases observationally, or is it worthwhile to talk about it even we can't distinguish them?
And what about things like Feynman's sum over histories method? This is really a mathematical technique, but it treats particles as taking all possible paths from a given starting point to a given destination, including paths that take a side trip to another galaxy on the way. Should we take that as a serious representation of what's really going on? If reality doesn't actually behave anything like that, why does the math work out so darn well?
Or is this all just philosophical nonsense, and we should just shut up and calculate? What do you think?