The Velocity Addition Formula
Velocity Addition Formula Updated: May 17, 2026 On the Electrodynamics of Moving Bodies Einstein-EDoMB-1905-Section §5 https://www.fourmilab.ch/etexts/einstein/specrel/www/ Einstein: Relativity, The Special and the General Theory, 1920, Chapter VI page 19, Chapter XIII page 45 https://www.google.com/books/edition/Relativity/n8QKAAAAIAAJ?hl=en&gbpv=1 Both sources show the velocity-addition-formula as it is today. Shown: V = ( v + w ) / ( 1 + vw/c² ) #### Abbreviations and notation SRT = spezielle Relativitätstheorie, Special Relativity rf = reduction factor ( 1 + vw/c² ) in the v-a-f. In what follows we have addition and subtraction. The reduction factor has to be adapted accordingly. af = adjustment factor ( 1 ± vw/c² ) As in most of SRT, we use left ← to ← right equation logic ( an assignment operator so-called ) rather than high school left = to = right, an identity. 5 ← 2 + 3 2 + 3 = 5 On occasion we change notation without changing anything on the ground. Bring...