It works by isolating the opponent in a seperate reqion of curved space-time. Just like a wormhole can transport a person from one part of the universe to another via a shortcut within space, this barrier relocates them back to the inside of the barrier upon exiting, via chakra signature of whatever was placed within it. Ace can sustain this barrier as long as he supplies chakra to it, as it consumes a medium amount of chakra at a constant rate.