Sorry I’ve not been back into this thread until now. I promised I’d give my
what with me having been the forum Christian since day one (and now officially doing ‘Christian’ for a day job too)
A couple of side observations first; the main one being that it will never be possible to prove with science what happens after you die. The scientific method was designed to observe and understand the material universe. What we’re discussing here is by definition outside of the material universe and therefore beyond science. I should also add that the scientific method was devised by European medieval monks who wanted to better understand God’s creation in order to deepen their worship of him.
It’s also worth noting that almost 350 years after the start of the Enlightenment, religious faith is alive and well and in fact thriving. Science has described the mechanics of the observable universe in sometimes exquisite detail but it is unable to answer the question ‘why?’ Human beings are hard-wired to search for meaning. Science cannot provide it (and humanists, for this reason, have tended to double down and insist there is no meaning, and explain away the human desire for meaning as an artefact of the way we’re constructed by the blind watchmaker of evolution).
The problem with humanism if strictly applied is it results in human relationships that are strictly transactional. There is little, perhaps no, room for selfless behaviour, yet the world, for all its brokenness, is full of examples of extreme love and sacrifice. There is something in the way we are made that I do not believe can adequately be explained away by ‘survival of the fittest’.
I believe we were all created by a God who is the very definition of love and that love is best seen in a period of history when God himself was born as a human being, to spend decades living and growing with us, feeling our brokenness and pain, teaching us there is a way to live, despite all of that, that is able to bring us into the presence of God himself. This Jesus exemplified that different way of living and ultimately proved that selfless love and sacrifice trumps everything else by dying, unjustly, a thief’s death but then beating even death and rising back to life.
While hanging on the cross alongside two thieves, he assured one of them - the one who understood Jesus had come from an eternal kingdom and was returning to it - to remember him. In return, Jesus assured the thief he would be with him in Paradise. And that, to answer the OP’s question, is what I am convinced happens when anyone dies with an appeal for Jesus to remember them. There is an eternal kingdom, and anyone who acknowledges its King may rest there. There is of course the matter of what happens when anyone dies without resting all their hope in Jesus. The best answer I can give to that is based on a work of C S Lewis which is not so well known outside of Christian circles, called ‘The Great Divorce’. In it, Lewis imagines an eternal landscape in which those who have refused to acknowledge the King of Heaven are unable to enter it because they remain preoccupied with all the same things that preoccupied them on earth. They simply can’t enter heaven because their preoccupation with themselves means they are unable to take in the reality of it.
Beyond that, I am convinced, as Jesus promised, that ultimately there is a physical resurrection and life on a new earth in which the material/spiritual bridge between heaven and earth has been re-made. In the end, we were created to be physical beings and that is what we will be. But that’s much further down the line than the question ‘what happens when we die’.