Light particles are best observed when not being observed. A paradox for both quantum and Newtonian physicists . The reason is simple. The act of observation alters everything. And that is because in observing light particles, an observer has to use light also in a hope to see what will happen. But by then, the light being used to observe the light particle affects the particles being observed. So it is futile attempt to observe light particles at all. The observer has no recourse but to give up and can only manage to come-up with probabilities and chances.
Just as the dilemma encountered in trying to pin down both the exact location and the momentum of a light particle at the same time, there is no way to answer how it feels like being asleep while in deep sleep. Only when it is done that a truthful result can be acquired. But even in delusional hope it can't be done. Someone has to be awake to ever answer the question about how it feels like to be asleep. But then the answer is necessarily incorrect. All that can be be done is imagine what it feels like.
The subjective position of the observer is obviously absent during deep sleep. There is no one to be questioned, no one to answer, no one to falsify, no one to confirm, and no one to interact. Nothing at all exactly as if there is nothing at all.With the subjective position absent, what's left to be done? No answer as if there is no way to both know and not know.
Upon waking up and after sometime the mind arises. Then thoughts accumulate. This sense of existence and self identity comes back forming again asserting itself a solid existence together with other individuals assumed to be having the same sense too. And there comes out the thing we call reality - an idea about this palpable existence.
But is it not true that the idea about reality, as all other ideas, only came about upon waking up from deep sleep? This must be true since any talks about any idea in sleep is impossible to conduct much like it is impossible to know how it feels being asleep while asleep. In deep sleep, how to tell what? Again, no answer as if there is no way to both know and not know. Only in the waking state that we ever come to talk what is what, how is how and so on.
Reality is a paradox. Any talk about is a distorted one like the light particle being affected by the light used to observe it and thus there is no way to get solid observer-independent answers. We want to know what real Reality is? Leave it alone. Because there is no real way to know real what except to just see it is as it is.