Recent content by Adrian59

Hooray, actually this is exactly my thought from the start. Apologies if the OP has mislead anyone. Also, as you have stated before I cannot see any justification for Aoyama et al claiming there derivation is analytic when it looks like a pure numerical technique. So if that is the case, the...

How about, 'using Feynman loop diagrams to calculate the Dyson series for the anomalous magnetic moment.'

I meant more than 'Oh, we use a computer algorithm'. That is, I was asking for more of an explanation of the mathematical processes.

Have complex QED calculations involving Feynman loops with say 891 (4th order) or 12672 (5th order) anything to do with calculating either the fine structure constant or the anomalous magnetic moment, accepting we need one of these to be experimentally measured? If so how does one deal with...

I am, can we move on to the other issues I've mentioned.

Why is that despite agreeing with you, you keep attributing the wrong idea to me? I agree that α cannot be derived from QED. I think it is pertinent to this thread to explore the issues raised by the Aoyama et al paper. It is deeply mathematical and that may be problematic to some contributors...

Still with you on this. However, my issue is how they go from Feynman loop calculations to the power series coefficients. They appear to jump from setting up the calculation. They state at the top of page 22 that they wish to 'explicitly work out the fourth order case', and by the middle of the...

Thanks for your input. Have you any opinion on the issue I raised in #59 with vanhees71.

That is my point entirely. So more specifically, what are Aoyama et al up to when they appear to start from such a loop diagram in section 4 of the referenced paper!

An example is from the Aoyama et al paper referenced in the OP. Equation 31 appears to be written from a loop diagram. Later on the paper the authors derive the 4th order coefficient with α to the power 8.

So, since we are agreed that α cannot be derived from first principles, it is only the coefficients of the power series that connects the anomalous magnetic moment to the fine structure constant (α) that are derived. I can see how one could do this by a straightforward numerical method. However...

So we do actually agree, as I thought all along. I will have to re-read the Aoyama et al paper to try and find what they are really up to. I can see if it is purely a numerical derivation how it works; but as I have said, and something you agreed on in #7 their terminology does appear rather...

Despite my best efforts you have repeatedly got the wrong end of the stick. I am in no way mistaken on this issue as I have said repeatedly in this thread. If you doubt this then you need to re-read the whole thread. In fact I have agreed with you consistently through the thread. My stated aim...

They both moved relative to others frame of reference, as phinds pointed out in in #14.

Apologies the posting has destroyed my carefully arranged response. The equation should read ∫ d^4p i /(p^2 - m^2 + iε) exp(-ip.(x-y) NB the bar notation represents division by 2π.