Originally Posted by Dave-H:
“The ring wouldn't cease to exist just because Rory has ceased to exist. It existed before he ever saw or touched it. It wouldn't have got into the TARDIS without his intervention though. I suspect that it didn't vanish because somehow being in the TARDIS preserved it.
Mind you, we've only actually seen the box since Rory went, not the ring itself!
”
“The ring wouldn't cease to exist just because Rory has ceased to exist. It existed before he ever saw or touched it. It wouldn't have got into the TARDIS without his intervention though. I suspect that it didn't vanish because somehow being in the TARDIS preserved it.
Mind you, we've only actually seen the box since Rory went, not the ring itself!
”
Isn't the TARDIS inteerior outside space and time at least for the duration someone's in it? Rory has gone but the ring was protected by being outside time. I wouldn't be surprised if it still has it's part to play.



