Scientific Ontology

c

Fundamental Constants

Speed of Light

Speed of electromagnetic radiation in vacuum; appears in relativity and E = mc².

metre per second (m/s)

Dimension: $[\,L T^{-1}\,]$

Fixed constant from the A-level data sheets.

3.00 × 10⁸ m/s

A-level value (vacuum)

Mass–Energy Equivalence

E = m c^2

Redshift

z = \dfrac{\Delta\lambda}{\lambda} \approx \dfrac{v}{c}

Mass–Energy (binding energy)

\Delta E = c^2 \Delta m