Slide 20 of 48
Notes:
Thus we demonstrate that E^2 - (pc)^2 is an invariant, because a particle’s rest-mass, m_0, is independent of its velocity, v. Therefore in a collision, [E^2-(pc)^2] before is the same as that afterwards.
This property will now be used to examine the case of an interaction of a gamma-ray with a low-energy photon.
