I recently came across this:


Starfleet has lately been in contact with several civilizations using advanced FTL propulsion. All these different technologies are casually designated "transwarp", although they all have few in common with the Excelsior Project. Actually, "Transwarp" has become a collective name for any technology suitable to overcome the limitations of conventional warp

Two fundamental principles of transwarp may be distinguished. The first is shipboard drive as it is used by the Voth in the Delta Quadrant. The data gathered on this principle by USS Voyager is scarce. It appears that Voth transwarp is indeed based on exploiting the lower subspace domains. But most likely, this technology does not envelop the ship which always remains in normal space, into a "warp bubble", like all warp drives of the Federation so far including Excelsior transwarp. Rather than that, the whole ship is pushed into subspace, comparable to subspace radio signals. Creating a field gradient strong enough to accomplish this is currently beyond the potential of Federation technology. It has been suggested, however, that this might be possible once the Warp 10 peak transitional threshold could be broken (Warp 10 referring to the pre-Excelsior scale!), which may act as a final barrier to the Transwarp I domain. Experiments performed in this field in the late 2360's turned out quite promising. A yet unconfirmed report from USS Voyager states that a shuttle with remodulated warp drive indeed managed to create ten nested layers and ultimately entered Transwarp I. This report, however, was rated not trustworthy by the Federation Science Council, although extensive sensor data including medical logs on the flight's effects on the passenger still remain to be verified. (There were premature rumors that the shuttle may even have reached Warp 10 in the meaning of "infinite speed", but this amateurish claim was quickly discarded by Federation scientists and was occasionally mentioned as a practical joke to cheer up boring presentations on scientific conferences.)

The other basic type of transwarp drive is the one that opens subspace ahead of a vessel, creating wormhole-like channels through which even more than one vessel could travel at a time. In order to avoid confusion, it has to be annotated that a conventional wormhole (like the Barzan Wormhole and fundamentally the artificial Bajoran Wormhole too) is actually a space inversion and not chiefly a subspace phenomenon, although many of its side effects become apparent in subspace too. Some transwarp channels, namely the transwarp network of the Borg and the corridors used by the Vaadwaur, are even reported to be permanent. Other sub-types of transwarp channels, including the technology now familiar as "quantum slipstream", resemble an elongated bubble which moves the ship through subspace and which may be controlled during the flight to a certain extent. Borg transwarp and slipstream drive require only minor modifications to the very propulsion systems of the ship. This is why they have already been successfully tested on Voyager in the years 2374 and 2375. Rather than continuous shipboard transwarp drive, Borg transwarp and slipstream drive are candidates to become the future propulsion technology of Starfleet. R&D activities on these topics are currently extensively funded. Warp field physicists and engineers, however, warn of a premature enthusiasm. They estimate that another ten years of fundamental research will be necessary until the basics of these technologies are fully understood and may be produced in series and safely integrated into Federation starships.

In the wake of the newly discovered technology, it has been suggested to modify the warp scale once again within the next decade, in order to take into account transwarp factors or, more precisely, layers of deeper subspace (Transwarp I, II etc.) that may be reached using transwarp drive. It remains to be seen whether this new scale will refer to the first transwarp level as "Transwarp I", or whether it will (again) include Warp 10, 11 etc. as a more familiar equivalent to "Transwarp I, II" etc.

(Theory by Bernd Schneider)  

A ceratin site  

The name of the author might set you in the right direction.

the equinox episode?

wasn’t that the slip stream drive?

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no, i'm not confused with the dauntless episode either.

it was where the alien changed bodies with tom paris and alien as tom stole ran way with that ship. and tom had to convince he was paris and not the alien bodie he had. and then the ship of teh alien was broken down or something and janeway wanted to help but then shifted bodies again...

can't recall the episode exactly but i know that ship folded space and had a very powerfull core that if it would explode bad things would have happened

Ohh, that one.