I should've noticed that you were joking, sorry about that. Just goes to show you, it's not always enough to write: “ [ smile ] ( Just kidding on that last statement. ) ”. Re: “ c = 1, Mass = Energy * ( 1 - v^2 )^-.5 ”. You commented: “ the energy can not be fixed as v changes. ”. Tell it to CERN. kg is obsolete. they no longer use it.