The Luminal Coupling Hypothesis: A Perceptual Extension of Special Relativity

Einstein’s special relativity defines the speed of light, c, as the ultimate limit for the motion of massive bodies. This limit has been validated experimentally and serves as a cornerstone of modern physics. However, it may represent not a fundamental barrier of nature, but the boundary of mutual perceptibility between matter and observers bound to subluminal frames of reference. This paper introduces the Luminal Coupling Hypothesis, which posits that c marks a transition where mass–energy does not cease to exist or convert in any absolute sense, but rather decouples from subluminal observation. We formalize this idea with a dimensionless luminal coupling factor P(v) = |1−v2/c2|that mirrors the Lorentz factor and tends to zero as v→c. For v<c, all predictions of SR are preserved; for v≥c, the hypothesis treats observables as projected through a coupling that vanishes at the luminal interface and may reappear upon re-coupling to P(v) >0. We outline potential observational consequences (e.g., beamed, time-compressed “boundary bursts”) and laboratory analogues, and we state falsifiable criteria that could rule the hypothesis out.