Not sure about "instantaneously" part. It's more like I send you a pull request and then I apply it to my repo and tell you to apply it to your repo and you get your repo in certain state which I knew upfront. Repo state teleportation!
Yeah, it know it's not exactly that either, but it's about as magical as that, AFAIU. Which doesn't say it's not useful - ability to merge pulls and get all the repos in certain state is hugely useful - but calling it "teleportation" implying that we're on the verge of being beamed up and down like StarTrek characters sounds a bit more pompous than warranted.