p'c2+moc m2v2c2+mgc mv'cme( 2 2 =E2 1) 1- E2=p2c2+moc 光子 m,=0 E=pc p= C E hy 又 E=mc2 ◆m= 2 _2 END 2 2 2 42 0 2 2 2 2 42 0 222 0 42 0 22242 0 22 1 1 )1( E c v cm c v c v cmcvm cmcvmcmcp = − = − −+ = +=+ 42 0 222 += cmcpE 光子 m0 = 0 = pcE c h c E p ν == 2 = mcE 22 c h c E m ν 又 == END