- #1
CAF123
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I've heard the statement that by computing just the leading-order (tree level) diagrams of a process and then computing the derivative of this result with respect to the mass should correspond to the evaluation of the mass counter term diagrams. Can someone explain why this statement is precisely true?
If we renormalise ##m_0 = Z_m m## then the bare amplitude $$A(m_0) \rightarrow A(Z_m m) = A(m) + m(Z_m-1) \frac{d A(m)}{dm} +O ((1-Z_m)^2)$$
But why is dA(m)/dm equal to the derivative of the tree level result?
If we renormalise ##m_0 = Z_m m## then the bare amplitude $$A(m_0) \rightarrow A(Z_m m) = A(m) + m(Z_m-1) \frac{d A(m)}{dm} +O ((1-Z_m)^2)$$
But why is dA(m)/dm equal to the derivative of the tree level result?