Physics Ontology

One map of physics, three ways in. Drill down on any quantity to see its units, the equations it lives in, and how its values span the universe.

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Relativity

Spacetime Interval

Invariant separation between two events in spacetime.

SI unit

metre (m)

Dimension: [L][\,L\,]

Other units

  • metre (m)

Order of magnitude

How values of spacetime interval span the physical world (in m, log scale).

Planck length
1.60 × 10-35 m
Observable universe
8.80 × 1026 m
Lower limit10-35 mUpper limit1026 m