Dimensional Slipstream
In Halo, the Shaw-Fujikawa Translight Engine allows ships to rupture normal space and enter "The Slipstream." Like the 40k Warp, it breaks physics, but unlike the Warp, there are no demons, just math.
Wake Turbulence
When a massive object (assault carrier) enters/exits Slipspace, it creates radiation (Cherenkov radiation) and gravitational distortions. This is how the UNSC detects Covenant fleets before they arrive. "Slipspace Rupture Detected."
The Debt
Slipspace travel builds up "debt" in the fabric of spacetime. If too many ships jump at once (or travel too fast), the dimension becomes unstable. Precursor roads famously ignored safe limits and eventually solidified spacetime itself.