i remember reading an intelligent post, that i mostly agree with, on a physics forum serveral moths ago from a guy steven re: afterlife/death.. although i tend to believe in a "kick started' universe because of expansion
The odds of death being a final goodbye seem very low (though even if that's the case, conscious experiences would seem effectively immortal because in either case it would seem only non-death is experienceable).
1) Even if life itself is rare, we know it's possible from the evidence. Given that this possibility exists, unless existance somehow stops ... which seems unlikely, then it's simply a matter of time before the improbable becomes inevitable.
2) Physically there's little evidence of anything ever being destroyed. Mass, energy and information change forms but don't appear to be forever removed from existance (and even if we observed this locally, there's a lot we can't physically see anyway).
3) There must be either a creative force or perpetuality to existance (I tend to assume everything must have always existed, instead of trying to describe why there was some beginning) because if nothing existed then there had to be at least the possibility of something else as well in order to "kick start" the universe.
So let's say that after death, the probability of life afterwards is now changed to 0 and made impossible. What is it that changes that probability and why, if it's a variable amount would it forever remain at 0? There doesn't seem any good explaination as to why a life, beginning with nothing, can end in nothing, but somehow this time the nothing is even less than before (if anything it would seem more likely that once something has been alive, it will be alive again, because in the second case proof of its existance is already available).
4) There's a non-physical aspect to consciousness that I don't believe either science or religion really has much knowledge about except as best guesses, but quantum mechanics tends to imply a non-locality to information by entangled relationships. For example, the physical body is constantly using new materials to refresh its form and disposing of older materials. There is no specific physical atom that's "you" and it would appear consciousness reattachs itself to the general form (as long as changes aren't too sudden), so even something like brain damage doesn't even destroy consciousness, though it can alter the characteristics of the "physical filter" by which perceptions are received.
I believe consciousness tends to center upon some local activity that's detectable and like Bose Einstein condensates, when it's isolated it expands its interactions outward, looking for something else to interact with. I think near death experiences are subjective and a product of the brain, though I can't say they aren't "real" because the rest of reality is subjective and largely influenced by the body and brain as well ... what's real, other than what you see, know and experience as real? Dreams may not be considered real, but when you're dreaming they're more real than an external reality you aren't experiencing at that moment, so reality is really subjective/personal and not always shared by everyone.
I'd hazard a guess physical memories don't "go along for the ride" after death, except in possibly some minor static/unchanging form. Most all knowledge is learned and appears to physically reside in the brain ("spacetime" and the universe is a giant memory of everything that's happened within this universe, IMO) and it would seem that if a soul exists, English (or whatever human language) wouldn't be the natural form of language, but instead conscious experience/perception is the raw sense and will/action is the form of speech/output. So I'm just saying that knowledge of this universe, along with the memories, and specific feelings or emotions would likely remain physically attached to this universe or a method of retention and translation would need to be possible. It would seem difficult if life occured again at another time and possibly even in a universe with different properties to both live under new circumstances as well as retain knowledge of disassociated/unrelated times, places or even the physical properties (for example, if you were an ant could you physically understand being a human or visa versus other than in some rudimentary ways and what relevance, if we assume evolutionary pressures exist, would there be to retain these memories and how could they be physically incorporated in teh brain etc.). On the other hand, the universe(s) itself is a giant repository of information and events that have occured within it and so memories of events could easily remain in a physical form.
Well, I'll leave it at that but the point is that it would seem very unlikely that life only occurs once, though it's difficult to imagine much of any way you can "take stuff with you" after death, unless you come back and reexperience it in a different form.
Also, consider this, I know personally I've had many experiences at some point in my life that were novel and unexpected - a new emotion or a new physical experience that I couldn't have imagined before experiencing it. I can't help but wonder "where" those come from? It would seem obvious the capability of experiencing them must have always been possible, but why do they take one specific form versus another? It appears rather random, IMO, and I can figure out why that would be the case if it's an unknown (by definition, you can't already know of something that's unknown ... until it becomes known), but anyway, my guess is that conscious experiences don't come in any specific form, though they likely possess qualitative and quantitive limits simply to remain as a coherent part of conscious experience, but it still leaves me wondering about what else can exist.