1) The "Arrow of Time" is not essential to the laws physics, so far as we can tell. There is no known reason that events must only progress in one direction. Which probably means that time itself is not a property of the universe but a property of our minds.
2) Physical reality is somehow determined by a probability field that is not actually settled to one of the possible alternatives until consciousness "collapses" it. This is called the "measurement problem". Things don't fully exist until someone looks at them. Which might also be a limitation of our minds rather than a property of the universe. In which case, the "collapse" of the probability field is not in the "real world" but in our minds.
Combining these leads to a staggering speculation -- the "real world" is everything possible at once, and we can (and must) choose what to perceive from the unimaginably vast possibilities. Note: This is NOT infinity! Infinity is very different from any measurable or calculable system. Mathematicians could possibly lecture about what infinity really is. I am not a mathematician. :) The universe is finite even though it is huge beyond any normal way of understanding. There is an estimate of the number of particles in the entire universe. Protons, electrons, etc. It's one of those crazy scientific notation numbers. And since there is a finite number of them, there is a finite number of "states" (inter-relations) they could be arranged in. That is also a crazy scientific notation number, naturally many times larger than the number of particles. We live on one small planet in this huge universe, and we have limited life spans, so the number of possible "worlds" or timelines is much smaller for us than for the entire universe. But it's still pretty huge.
We know very well that the "real" physical world is not what we perceive with our senses. Solid matter is actually fields of force, for example, and mostly empty space. But our minds, our ability to think about things, are built mostly from our experience in the first "real" world of our senses. It has been a slow process building up the abstract ideas that can begin to let us understand beyond our sensory world. The "many worlds" hypothesis is just a speculation using some of those abstract ideas. But it is an amazing image, isn't it?
Edited 1 time(s). Last edit at 12-Jan-20 16:50 by Nolondil.