Abraham kwukwara (dị ka Lorentz na 1899) na oke a na-adaberekwa na ntụziaka ma mepụta aha "Longitudinal" na "Transverse" Mass. N'adịghị ka Lorentz, ọ tinyeghị Contraction Hypothesis n'echiche ya, yabụ okwu oke ya dị iche na nke Lorentz. Dabere na ọrụ ndị gara aga na igwe eletrọniki, Friedrich Hasenöhrl tụrụ aro na akụkụ nke oke nke ahụ (nke ọ kpọrọ ihe pụtara ìhè) nwere ike iche na radieshon na-agbanye gburugburu oghere. "Ihe pụtara ìhè" nke radieshon na-adabere na okpomọkụ (n'ihi na ọ na-ewepụta radieshon) ma na-adaba na ike ya.
okpomọkụ