Is this a simulation?
If so, "Even the Bible doesn’t tell us why only who."
It actually does suggest why if you look quite closely. It is a bit ambiguous though and whether I like what it says or not is another issue.
"Our entire past, the history of the universe as a whole, might change from moment to moment in the external universe’s time". For what it's worth, Christianity says that is not the case, though Islam says it is so.
"How time works in the external universe may be entirely different". True, but we don't know what that is and it is key.
I read this because for an odd reason related to human survival, it is a topic of interest to me. When got to the end of it I was a bit disappointed. It is a masterful mathematical analysis and offers fascinating understanding, but is of only limited value because there are easier ways to get to that... if not as clearly. The key is time and we just don't know what that means. The reason I am interested in this topic though is where you started, the WHY? "If your life is simply being simulated in some external reality". If it is a simulation, what is the purpose? If you could figure that out, it would be another approach to solving the questions you ask. Is it because "they might be our descendants trying to figure out how we lived"? I have another thought on that question. I study long term human survival as we transition from the hunter-gatherer tribal world to the new ecology we call civilization. One of the biggest challenges we are going to face is the learning curve. This "here and now" is such a unique time of change. The larger changes in ecology are greater than any species has ever attempted to make or survive. In the shorter term, change is just as extreme. I rode a bicycle on trails in farmland as a child. I made a living using power tools. I now tour the world in my Oculus and use AI to give me code snippets. I am still though, by nature, most adapted to the world I came from. As a student of where humans can go, I know it is a very strange place, with challenges and dangers we wouldn't suspect. I wonder if this unique, unusual world of change we are in is actually a training ground necessary to make it even possible to adapt to what we would call the future. Is it a rite of passage (as the Bible might suggest)? I see that required degree of adaptation as one of the greatest challenges humans face. Is a simulation the solution. Am I a "child" in some future where my "advanced tribal brain" is being trained to cope with a world my brain is not well naturally adapted to ... yet. Is t to ge tme ready for the 'real" world?
Considering that as the reason for the simulation, the WHY, the moral Why, how humans think, seems more important perhaps than the mathematics of it. Well, it's the kind of answers I like, though this mathematical one is pretty cool too.
