Ohorizon

Ohorizon is a fictional concept used in speculative fiction and academic discussions to describe a boundary that separates distinct perceptual or physical regimes. Unlike conventional horizons, Ohorizon is conceived as a tunable, observer-dependent boundary that can vary with perspective, technology, or environmental conditions. In most treatments, crossing the Ohorizon alters the rules governing phenomena such as causality, measurement, or the behavior of matter and energy, creating a domain where standard physics may differ from that of the familiar world.

The term combines the word horizon with the interjection 'oh' to emphasize sudden recognition of a boundary and to signal its speculative nature. It is not a term used in established physical theories.

In fiction and worldbuilding, Ohorizon is used as a plot device and as a metaphor for limits of knowledge, observation, and agency. It is often depicted with specialized instruments or methods that enable detection or navigation near the boundary, and with consequences for observers who cross it.

Scholars and critics view Ohorizon as a useful way to discuss epistemic boundaries, measurement, and the relationship between observer and observed. Some note that it invites imaginative exploration of alternative physical laws while cautioning against conflating metaphor with established science.

See also: horizon, event horizon, cosmology, epistemology, parallel universes.