Spacetime Continuum
A 4D mathematical continuum combining 3D space and 1D time into a unified pseudo-Riemannian manifold.
Governing formula
ds² = g_μν dx^μ dx^ν (4D Pseudo-Riemannian Manifold)
SI unit
4D Manifold (3 Space + 1 Time)
In depth
In relativity, space and time are not independent absolute entities but interconnected dimensions. Events are specified by four coordinates (ct, x, y, z). Spacetime metric g_μν defines distances and interval invariants between events.
Examples in the real world
Mapping planetary orbits as free-fall geodesic paths through the 4D spacetime continuum surrounding the Sun.