Subspace flux isolator

In an alternate timeline, a subspace flux isolator was a device invented by Jake Sisko used to open up a path into subspace.

In 2422, an aged Jake used this device aboard the USS Defiant (2370) in an attempt to retrieve his father, who had been trapped in subspace fifty years previously. Timing his use of the isolator to coincide with a subspace inversion of the Bajoran wormhole, the device worked, but instead of pulling his father out of subspace, it drew him into a subspace fragment where he was able to interact with his father, due to a subspace link which had been created between them at the time of the initial accident. Jake was soon returned to normal space however, his attempt to rescue his father failing. The timeline in which these events occurred was negated thirty-eight years later when Jake committed suicide, thereby severing the link between them and sending his father back in time to the moment of the initial accident, where he was able to change history by avoiding the energy surge which pulled him into subspace in the first place.