Note 1 to entry: The Lorentz factor is used, for example, for relativistic mass $m^{\prime }=\gamma m$, Lorentz contraction $d^{\prime }=d/\gamma$, and time dilatation $\Delta t\prime =\gamma \Delta t$.

Note 2 to entry: For the transfer of matter, $1\le \gamma <\infty$.

Note 3 to entry: The coherent SI unit of the Lorentz factor is one, symbol 1.