Musi waJune 5, 1905, Henri Poincaré akapa pfupiso yebasa rakavhara zvikanganiso zvaivepo zvebasa raLorentz. (Iri pepa pfupi raive nemhedzisiro yebasa rakazara raizoburitswa gare gare, muna Ndira 1906.) Akaratidza kuti Lorentz's equations of electrodynamics yakanga isiri Lorentz-covariant. Saka akanongedzera hunhu hweboka rekushandurwa, uye akaruramisa mafomula aLorentz ekushandurwa kwechaji density uye ikozvino density (iyo yaisanganisira zvine mutsindo iyo relativistic velocity-addition fomula, iyo yaakagadzira muna Chivabvu mutsamba kuna Lorentz). Poincaré akashandisa izwi rekuti "Lorentz shanduko", uye akapa mafomura avo akaenzana. Akaburitswa zuva iri mwedzi minomwe gare gare.
23 July