nonspacetime

Nonspacetime is a term used in philosophy and physics to refer to structures, regimes, or ontological categories that do not possess spatiotemporal properties. It is not a standard physical field, but a way of characterizing approaches in which space and time are not taken as fundamental constituents of reality, but rather as emergent features at larger scales.

In theoretical physics, nonspacetime often appears in discussions of quantum gravity and pregeometry. Some programs treat spacetime as arising from more basic nonspatiotemporal substrates. For example, causal set theory describes a fundamental ordering of events without a continuous spacetime manifold, while loop quantum gravity describes geometry in terms of discrete quantum states that give rise to smooth spacetime only in appropriate limits. In holographic contexts such as the AdS/CFT correspondence, a lower-dimensional nongravitational theory can encode information about a higher-dimensional spacetime, suggesting that spacetime geometry may be secondary to more fundamental nonspatiotemporal data.

The idea implies that locality, causality, and metric structure could be emergent rather than fundamental. If so, our classical notions of positions and durations would be effective descriptions, valid only within a certain regime. Critics argue that the label nonspacetime can be vague or misleading, and that a complete theory must eventually recover spacetime in a precise way. Nevertheless, the concept highlights ongoing questions about the foundations of spacetime and the nature of reality. See also emergent spacetime, pregeometry, holography, quantum gravity.