oooh damnit! I spent forever typing out my thoughts on this video only to have it disappear. I gues the universe didnt like my thoughts. I will try again, impatiently now.
quantum physics is the fairy tale world of science, IMHO. The marble never passes through both openings. ever. an object cannot be in two places at one time. I postulate that te marbles are instead rinding on waves, and it is the waves that, by their nature, pass through the openings at the same time, and any particle small enough to have its momentum affected by the wave is going to show movement patterns consistent with waves. And yes, when we use instrumentation to try to measure this, we do affect the motion of the marbles, or indeed the waves themselves. It only works in a natural state.
The universe does not "know' i am observing it. That is just theory, fancy talk. For example. My husband is not observing me right now. From his perspective I am both awake and asleep. He does not know which until he joins me and can see me. BUT, I am most definitely awake. I am sitting here, awake. Forget that my awakeness is being witnessed by you guys by seeing what I am typing. I was also awake a few minutes ago watching a video, unobserved. The lack of observation does not make me exist in some sort of suspended multi-state.