Perfectly mundane and perfectly in line with the current principles of physics. That there's no 'thing' to be reborn in the first place. No new 'thing' comes into being in childbirth and no 'thing' is lost when the body systems decouple. The conservation laws of physics aren't violated. Matter and energy combine temporarily, then keep going their merry ways. It's OK to describe people and minds as emergent properties, because emergent properties aren't fundamental entities; they're dependent upon matter and energy for their quasi-existence. Rebirth is a hi-jacking of the pre-existing concept of reincarnation, just as the Buddha hi-jacked the term 'kamma' and made it mean something quite opposed to the original. Reincarnation pre-supposes entities and essences that might transmigrate; rebirth doesn't. The simile of the poetry teacher is the clearest example to me. Phenomena replicate, not people, because there are no people (selves) in the first place. That replication of phenomena is rebirth, as far as I can tell at the moment. Of course, my understanding will change over time.