- #1

- 991

- 1

m/(1-u2/c2)1/2=m(1+u’V/c2)/(1-u’2/c2)1/2(1-V2/c2)1/2 (1)

mu/(1-u2/c2)1/2=m(u’+V)/(1-u’2/c2)1/2(1-V2/c2)1/2 (2)

where m represents the Newtonian mass of a particle that moves with speed u relative to the inertial reference frame I and with velocity u’ relative to the inertial reference frame I’ in the positive direction of the OX(O’X’) axes, I’ moving with velocity V relative to I, all velocities showing in the positive direction of the overlapped axes.

An exercised eye recognizes in (1) the transformation equation for mass whereas in (2) the transformation for momentum. Physicists, known as starters or developers of trends (godfathers?), combine the physical quantities that appear in (1) and (2) presenting them as

M=(M’+p’V/c2)/(1-V2/c2)1/2

P=(P’+M’V)/(1-V2/c2)1/2

being obliged to find out names for M,M’,P and P’. From that point the problem is no more then semantics. What names would you prefer? Has the name we choose some importance as long as we know that

M=m/(1-u2/c2)1/2

M’=m/(1-u’2/c2)1/2 P=mu/(1-u2/c2)1/2

P’=mu’(1-u’2/c2)1/2.

Is it compulsory to find out names for them?

I get accustomed with harsh answers!