The universe was vast and boundless. Even with warp technology, warships capable of entering hyperspace could never hope to explore the edge of the universe within their lifetimes.
The Level 5 Alvin Galaxy was merely one spiral arm of the Gibraltar Galaxy. The Gibraltar Galaxy, controlled by a Level 6 civilization, had five spiral arms in total: Alvin, Aibute, Guste, Troy, and Gusilov, corresponding to five Level 5 civilizations!
Even for an Alvin warship traveling from one end of the Alvin Spiral Arm to the other, using space jumps intermittently along the way, the journey would take at least two years! No one knew how many galaxies in the universe were larger than the Gibraltar Galaxy. If one relied solely on space-jump travel, reaching another Level 6 civilization would probably take no fewer than twenty years!
Such distances meant that two large galaxies were effectively isolated from one another. Meaningful communication between them was difficult—after all, a round trip took forty years. By the time forty years had passed, many things might have changed beyond recognition! Merchant associations could not exchange goods—the transportation costs were too high; nations could not form alliances—after forty years, a civilization might well have changed rulers...
It was not until the emergence of wormholes that the problem of connecting two large galaxies was truly solved!
Wormholes existed in the gap between normal space and negative space. They were cosmic miracles capable of transporting travelers across tens of millions of light-years without requiring space jumps. If the teleportation arrays of magical civilizations and the space-jump technology of technological civilizations were crystallizations of human wisdom and capability, then wormholes were masterpieces of the vast universe itself.
There were three types of wormholes. The first was intra-galactic wormholes, which linked two distant locations within a galaxy. The second