Sii qor faqradan - Aragtida Big Bang waxay ka soo baxday aragtiyo ku saabsan qaab dhismeedka caalamka iyo fikrado ku saabsan aragtida. Sanadkii 1912, Vesto Slipher wuxuu cabiray wareejintii ugu horreysay ee Doppler ee "Nebula spiral" (Nebula spiral waa erey duugoobay oo loogu talagalay galaxiyada spiral), wuxuuna si dhakhso leh u ogaaday in ku dhowaad dhammaan nebulayaasha noocan oo kale ah ay ka fogaadeen Dhulka. ma uusan fahansanayn macnaha guud ee arintan, xaqiiqdii waqtigaas arintan aad bay u muran badneyd
Nebulaas waxay ahaayeen ama ma'aha "Jaangooyooyin Jasiirad ah" oo ka baxsan Milky Way. Toban sano ka dib, Alexander Friedmann, oo Ruush ah cilmiga caalamka iyo xisaabta, wuxuu ka soo saaray isle'egaha Friedmann ee Einstein field equations, isagoo tusay in caalamku uu fidayo si ka duwan qaabka caalamka ee joogtada ah ee uu ku dooday Albert Einstein waqtigaas.