Well, that seems vague, but here are some of the things about quantum physics that people find odd: 1) We intuitively think of the past as certain and the futu

Well, that seems vague, but here are some of the things about quantum physics that people find odd: 1) We intuitively think of the past as certain and the future as unwritten. You seem to be suggesting that both are written. But quantum physics says that both are unwritten. So it's exactly the opposite. Just as there are many possible futures from this point, there are also many pasts leading to this point, and that's why you get interference patterns and so forth. So, it's not that there is one past and many futures, nor is it the case that there is one past and one future. There are many pasts and many futures, and they are all mathematically, measurably, equally real. (But not all equally probable) 2) Probabilities in quantum physics have a phase angle, which is why they can sum or they can cancel out.