- #1
shadi_s10
- 89
- 0
Dear all,
I am taking 'field theory' course this semster and I am reading 'quantum field theory' by mandl and shaw.
In chapter 8, equation (8.9) we see:
E_1 E_2 v_rel=〖[(p_1 p_2 )^2-m_1^2 m_2^2]〗^(1/2)
and we know that as p is a four vector:
p=(E,P)=m
so p_1 p_2 = m_1 m_2
!
Isn't it strange?!
I think the right hand side of eq(8.9)should be zero then!
what am I donig wrong?!
I am taking 'field theory' course this semster and I am reading 'quantum field theory' by mandl and shaw.
In chapter 8, equation (8.9) we see:
E_1 E_2 v_rel=〖[(p_1 p_2 )^2-m_1^2 m_2^2]〗^(1/2)
and we know that as p is a four vector:
p=(E,P)=m
so p_1 p_2 = m_1 m_2
!
Isn't it strange?!
I think the right hand side of eq(8.9)should be zero then!
what am I donig wrong?!