The normalization group in quantum theory [87]

Abstract

In order to discuss complex interactions, we generalize Dyson’s method¹⁾ in the following way: Consider a given n-th order contribution t,o the S-matrix

$$ \begin{gathered} S_{n m} \left[ V \right] (u'' \phi '' \ldots /u' \ldots ) = const. \prod\limits_i {\left( {\int {Vdx_i } } \right)u''} ^\dag (x_1 )\phi ''^\dag (x_2 )\sigma _{M_1 } (x_1 ..x_i ..) \cdot \hfill \\ .\Delta (x_i x_k ) \ldots u' (x_l ) \ldots \sigma _{M_2 } \ldots \sigma _{M_n } . \hfill \\ \end{gathered} $$

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