Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Einstein (1907b) ya tattauna batun ko, a cikin jikin rigid, da kuma a duk sauran lokuta, saurin bayanai na iya wuce saurin haske, kuma ya bayyana cewa za a iya watsa bayanai a ƙarƙashin waɗannan yanayi zuwa baya, don haka za a keta abin da ya faru. Tun da wannan ya saba wa kowane kwarewa, ana ganin saurin haske ba zai yiwu ba. Ya kara da cewa dole ne a samar da karfin jiki mai tsauri a cikin tsarin SR. A ƙarshe, Max Born (1909) a cikin aikin aikinsa da aka ambata a sama game da hanzarta motsi, ya yi ƙoƙarin haɗa da ra'ayi na jikin jiki a cikin SR. Koyaya, Paul Ehrenfest (1909) ya nuna cewa ra'ayin Born ya haifar da abin da ake kira Ehrenfest paradox, wanda, saboda raguwar tsayi, kewayon faifai mai juyawa ya ragu yayin da radius ya kasance iri ɗaya. Gustav Herglotz (1910), Fritz Noether (1910), da kuma von Laue (1911) sun yi la'akari da wannan tambayar. Laue ya gane cewa ra'ayi na al'ada ba shi da amfani a cikin SR tun lokacin da jikin "m" yana da digiri na 'yanci da yawa. Duk da haka, yayin da ma'anar Born ba ta da amfani a jikin jiki, yana da amfani sosai wajen kwatanta motsi na jiki. Dangane da Ehrenfest paradox, an kuma tattauna (by Vladimir Varićak da sauransu) ko raguwar tsayi "na gaske" ne ko "bayyane", kuma ko akwai bambanci tsakanin raguwar motsi na Lorentz da raguwar motsi na Einstein. Duk da haka, ya fi dacewa da jayayya game da kalmomi saboda, kamar yadda Einstein ya ce, ƙuntataccen tsawo na kinematic yana da "bayyane" ga mai lura da motsi, amma ga mai lura da shi yana da "ainihin" kuma sakamakon zai iya auna.  Tambaya: Mene ne ake ganin ba zai yiwu ba?
saurin haske