Albert_Einstein
Disgyrchiant
Twll_du
Perthnasedd_cyffredinol
Gofod-amser
Cyflymder_golau
David_Hilbert
Deddf_disgyrchedd_cyffredinol_Newton
Ton_ddisgyrchol
Gofod_pedwar_dimensiwn
Perthnasedd_arbennig
Microlensio_dwysterol