Subspace bubble

A subspace bubble is an encompassing energy field, which can be used to protect objects or people from various environmental effects.

A subspace bubble has the capability to form around a person. This variation can be used bypass a force field.

In 2371, an exploding microscopic singularity passed through the Sol system, and created a subspace bubble around the USS Defiant. This isolated the ship and its crew from the changes made in their timeline, allowing the ship to observe an alternate timeline where Starfleet did not exist. In this timeline, the Alpha Quadrant was controlled by the Romulan Star Empire. The altered timeline was restored to normal when the Defiant crew made sure that past events unfolded as told in their history books.