- #1
dyn
- 773
- 61
Hi.
If the 4-momentum in SR is given by p = m γ(v) ( 1 , v ) then in the rest frame of a particle the 4-momentum is ( m , 0 , 0 , 0 ) using c=1 units. This uses the fact that because v = 0 then γ(v) = 1.
I'm confused about this last sentence. The gamma factor is used for the relative velocity between 2 inertial frames but in the rest frame the particle is at rest relative to every other inertial frame so how can we specify a gamma factor ?
If the 4-momentum in SR is given by p = m γ(v) ( 1 , v ) then in the rest frame of a particle the 4-momentum is ( m , 0 , 0 , 0 ) using c=1 units. This uses the fact that because v = 0 then γ(v) = 1.
I'm confused about this last sentence. The gamma factor is used for the relative velocity between 2 inertial frames but in the rest frame the particle is at rest relative to every other inertial frame so how can we specify a gamma factor ?