There are reportedly four (4) theories on what happens when we die:
1) We have a soul and that soul goes on living in the afterlife.
2) Our mind can go on functioning even without our physical bodies.
3) We never really die. It has been argued that since we perceive time and space only as a result of our consciousness, we can’t really die. We can simply take any moment in time and use that as a new frame of reference.
4) Nothing. When we die, we’re dead. That’s it.