Preserved Causality Hypothesis

A hypothesis in theoretical physics and FTL research that states that even with faster‑than‑light travel or communication, causality would not be violated because some underlying mechanism would prevent messages from being received before they are sent. This could be due to the topology of spacetime (e.g., wormholes that are time‑like but still globally causal), limits on the kinds of trajectories that can be realized, or quantum effects that enforce temporal ordering. The hypothesis is essential for making FTL concepts physically plausible, as the standard argument against FTL is that it would allow backward time travel and paradoxes. If causality is preserved in all FTL scenarios, then such paradoxes would be impossible.

Example: “She defended the preserved causality hypothesis by showing that any FTL signal would still obey a modified light cone—it could outrun light but not its own past, preserving cause before effect.”

Preserved Causality Hypothesis by Dumu The Void April 25, 2026