Spatiotemporale

Spatiotemporale, or spacetime in English, refers to the concept that space and time form a single four‑dimensional continuum rather than two separate, independent entities. In physics, this unification underpins how events are described and how physical laws operate across different observers and reference frames.

In special relativity, spacetime is modeled as a flat four‑dimensional manifold with coordinates (t, x, y, z). The geometry is encoded by a metric, most commonly the Minkowski metric, which yields the invariant spacetime interval ds^2 = -c^2 dt^2 + dx^2 + dy^2 + dz^2 (sign conventions vary). This structure leads to phenomena such as the relativity of simultaneity, time dilation, and length contraction, and it requires that the laws of physics be locally Lorentz invariant.

In general relativity, spacetime becomes dynamic and curved in response to energy and momentum. Gravity is described as the curvature of spacetime, and free particles follow geodesics in this curved geometry. The spacetime interval remains a core invariant, but its interpretation changes with curvature. Predictions include gravitational time dilation, light deflection by mass, and the expansion of the universe.

Beyond classical theories, spacetime serves as the background for quantum field theories, although a complete quantum theory of gravity—one that fully quantizes spacetime itself—remains an open area of research. In cosmology, spacetime dynamics explain cosmic expansion and the large‑scale structure of the universe.

The term spatiotemporal also appears in data analysis and computer science, where models describe how physical quantities vary across both space and time, such as in video processing, geospatial data, and sensor networks.