User blog comment:Damac1214/Black Ops 2 - Origins Achievement List/@comment-1892823-20130823033555

I can see it now. Agartha is also like a timewarp (similar to the teleporters). So basically if Richtofen (future) told Maxis (future) that Sam is in Agartha, Sam could have been send back to the past but in a parallel plane where the ghost must be sent free.