Diagrams shifted denominators

This expression should be compared with the correction of order a Za) to the Lamb shift in (3.34). Both expressions have the same physical origin, they correspond to the radiative insertions in the diagrams with two external photons, may be calculated in the skeleton diagram approach, and do not contain a factor tt in the denominators. The reasons for its absence were discussed in the end of Subsect. 3.3.1. 

The terms itu CLF(/ E+i t) in the denominator of the potentiostatic EHD expression (6-33) explain why all the experimental diagrams are shifted towards lower p values with respect to the one obtained on a uniformly accessible Pt electrode, which matches the theoretical predictions and is independent of Q. The non-reducibility of the experimental diagrams is caused by the existence of a modulated current due to charging and discharging of the polymer redox capacitance. Since this... 

We see that the whole effect of the infinite summation (91) appeared in the so-called denominator shift [compare expressions (81) and (95)]. The denominator shift just presented, corresponds to putting the interaction line (91) between two particle lines. For this reason we talk about the diagonal particle-particle ladder diagram. 

Thus the summation of a geometric series, just as before, results in a shifted energy denominator. Now if one were to sum all possible diagrams generated by the prescription given above, one would find... 

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