It's been established that Star Trek consists of a multiverse, with matter from each respective universe having a distinct "quantum signature" which cannot be changed by any known process.
This has been used to identify members of different universes in the past - Worf's duplicates from TNG S7: Parallels, and the recent mirror universe episodes of Star Trek: Discovery.
However, the Kelvin Timeline appears to have been created from the Prime Timeline, due a temporal incursion by Nero. They would imply that either both universes have the same quantum signature, the Kelvin Timeline was already its own universe with its own signature, or the quantum signature of the universe somehow changed due to Nero's incursion.
So if prime-universe Spock compared his quantum signature to the inhabitants of the Kelvin Timeline - would they be the same or different?