Peacekeepers of the Vast/Hyperspace

The fastest way to move information is still with jars full of memory cards on the back of a freighter. Just… don't lose the freighter in hyperspace.

Hyperspace, or H-space, is second dimension of space separated from normalspace, or N-Space, by a thin veil between dimensions. To transition between dimensions jump by way of a jump window. The normalspace universe is far too vast to send things or information across in a timely manner. Hyperspace is an infinite sphere, much like normalspace, empty except for the poorly understood gravitational eddies that cut through it and sentient made objects maintained there. Hyperspace is significantly compressed with each point in H-space having a one-to-many correspondence with N-space, allowing good transit times even when traveling at low fractions of c. The topography of H-space is constantly shifting and the emptiness glows an unpleasant red due to the gravitational forces. Sources of energy on the other hand, tend to glow blue. Travel by beacon and known route is advised.

Hyperspace is accessible by jumping - the use of a focused gravity beam to pierce the veil between n-space and h-space and accelerate an object through the resulting outgoing jump window. The energy requirements of piercing, and accelerating the void are significant, and without properly tuned shielding, the jump will exert significant tidal forces on the jumping object. But so long as one has access to a sufficiently powerful gravity beam and sufficient normal-space velocity to pass through the portal intact, one can enter hyperspace.

Exiting hyperspace is both simpler and much harder to survive. N-space objects do not belong in hyperspace, and will slide down the jump gradient towards N-space. The jump gradient is exponentially steeper in H-space as the corresponding N-spaces gets closer to a gravity well. Unless counteracted with station-keeping, any object will eventually slide down the natural jump gradient and enter N-space, usually near a powerful gravity source. Station-keeping energy requirements grow with the mass of an object in H-Space and reduces with speed. Transitioning from H-space to N-space can result in jump dissociation. Due to the one-to-many correspondence, molecules were once adjacent in H-Space can end up separated by a fair distance in N-space. Opening an incoming jump window and shielding allows precise and safe travel, with lower energy requirements than opening the outgoing jump window into H-Space in the first place. It is also possible to deliberately transit intact from N-Space to H-space by sliding down the natural jump gradient, this a little less safe and a lot less precise.

Practically speaking, jump windows are one-way only for any thing with more than a photon's worth of a mass. In theory a ship could transition the wrong way by speeding through the window before the gradient dragged them down. No one knows what the required amount of speed and energy. All experiments attempting it have ended catastrophically.