Here is a quick rundown of the theory. The universe is teeming with invisible, intangible threads. They act as conduits for various types of energy, moving that energy between points instantly. If you had the ability to interact with them you could pinch one off, sort of like a garden hose. The pressure of the energy pushing through the thread will instantly take any obstructing matter with it. That’s how they can move you across the universe instantly. However, these threads are constantly writhing, and popping in and out of existence. You would have no way to know where a thread begins and ends. And the odds of finding a way back home are near-infinity against you.
Early on this type of travel looked like the picture I drew today. It was fun to draw, but no longer quite so accurate.