Valen class cruiser in transit in Quantum space.
Quantum space was a dimension discovered by the Interstellar Alliance from technology acquired when it was left behind by the Vorlons when they went beyond the Rim.
Quantum space allowed ships to travel twice as fast when compared to Hyperspace; however, the entry into this realm was even more violent than opening a jump point. The new Valen class diplomatic liners were equipped with the ability to enter into Quantum space. A ship leaving Quantum space could create an exiting jump point inside a regular Jumpgate, such as the one orbiting Babylon 5. [1]
- Its not explained where the technology was discovered or why the Vorlons were never actively seen using it. Its possible the development of Quantum space was created when the Vorlons were looking for Thirdspace.