Comment by manofmanysmiles

I'd propose using our current view of physical reality to own a subset of the UIID + version field if new physics is discovered.

10-20 bits: version/epoch

10-20 bits: cosmic region

40 bits: galaxy ID

40 bits: stellar/planetary address

64 bits: local timestamp

This avoids the potentially pathological long chain of provenance, and also encodes coordinates into it.

Every billion years or so it probably makes sense to re-partion.