This may be inappropriate for this forum. If so, please suggest where I should post a question like this. Thanks. Brian Green writing in the NY Times: << Instead, the proponents of quantum theory claimed, reality consists of a haze of all possibilities - all trajectories - mutually commingling and simultaneously unfolding. And why don't we see this? According to the quantum doctrine, when we make a measurement or perform an observation, we force the myriad possibilities to ante up, snap out of the haze and settle on a single outcome. But between observations - when we are not looking - reality consists entirely of jostling possibilities. Quantum reality, in other words, remains ambiguous until measured. The reality of common perception is thus merely a definitive-looking veneer obscuring the internal workings of a highly uncertain cosmos. Which is where Einstein drew a line in the sand. A universe of this sort offended him; he could not accept, as he put it, that "the Old One" would so profoundly incorporate a hidden element of happenstance in the nature of reality. Einstein quipped to his quantum colleagues, "Do you really think the Moon is not there when you're not looking?" and set himself the Herculean task of reworking the laws of physics to resurrect conventional reality. >> When I was a young student of elementary physics, the above description of quantum theory is what I called "uncertainty of fact". Events on a small scale have many outcomes, and only when someone looks at such an event, do the many outcomes resolve into a single observed outcome. Schrödinger's cat is the famous outcome of this thinking, or Einstein's questioning of the moon's existence when no one is looking at it. I have always believed that this was BS, and that the issue was uncertainty of knowledge rather than uncertainty of fact. Small events have one outcome, even when no one is looking. This one outcome is not predictable in advance, since the theory allows for many possible outcomes, each one with a probability, and the sum of these probabilities being 1. I find this much easier to swallow than Schrödinger's cat. I never went on to master physics, but I have continued to wonder about this question. Recently I asked a friend who is a professor of physics at a university, and he agreed with the second interpretation. Now I wonder why Brian Green and other certified geniuses apparently buy the first interpretation.