I've had a lot of long talks with a really good friend of mine who has had a lot of free time and likes to think about deep philosophical questions.
He actually found a way to combine physics with spirituality and things like a 'soul' and stuff like that. Even reincarnation is incorporated.
It's extremely interesting but he is way better at explaining his model than me.
I still haven't found an argument against his model, it's just so perfect. I can't find a way to tackle it.
He said that our souls are electromagnetic fields, kind of interwoven in our physical bodies.
That every moment of time does exist, but not in multiple universes or something. Every moment of time is just 'known' to the 'whole'.
And yes, we are all one.