Folded-space transporter
From Memory Alpha, the free Star Trek reference
A folded-space transporter is a device that moves objects via a dimensional shift. In the Federation, the principles of folded-space transport was first proposed in the Elway Theorem, though it was discarded in the mid-22nd century due to its dangerous effects on humanoid tissue.
The Ansata separatist movement of Rutia IV uses a folded-space transporter called an inverter, based on the Elway Theorem. Ansata leader Kyril Finn credited the inverter with reinvigorating his group despite the fatal results of its use, because it allowed his forces to move quickly and with complete surprise anywhere they wished, including areas protected by force fields, and to escape without fear of being tracked.
In 2366, the Ansata abducted Doctor Beverly Crusher of the USS Enterprise-D in the hopes that she could find a way to reverse their cellular degeneration. They also used the inverter to attack the Enterprise, hoping to force the Federation to intervene on Rutia IV. The Enterprise crew was eventually able to pinpoint the power source of the inverter and rescue Crusher. (TNG: "The High Ground")
The Sikarians of the Delta Quadrant employ a type of folded-space transporter called a spatial trajector, which had a range of some 40,000 light years. The crew of the USS Voyager attempted unsuccessfully to negotiate for this technology in 2371. When some members of the crew obtained a trajector module through other means, they learned that the trajector was fundamentally incompatible with Federation technology. (VOY: "Prime Factors")
