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- TL;DR Summary
- Basic question for a theoretical physicist regarding perturbation theory calculations.

We know that we need to go to 5th order in perturbation theory to match 10 decimals of g-2 for electron, theory vs. experiment. But let us not assume QED is pure and independent, but it's a lower energy limit of GSW (not Green-Schwartz-Witten from superstrings) electroweak theory. Has anyone theoretically computed a 1st (2nd or whatever) order correction to the g-2 momentum of the electron? How many one loops would be required? Which decimal of g-2 only from QED would it affect?

P.S. I hope this is not a dumb question (like there is some conservation law prohibiting the 3 Ws to appear in the possible tree-level or loop FDs). While studying physics ages ago it just did not pop up in my mind.

P.S. I hope this is not a dumb question (like there is some conservation law prohibiting the 3 Ws to appear in the possible tree-level or loop FDs). While studying physics ages ago it just did not pop up in my mind.