Does anybody have more insights regarding https://www.nature.com/articles/ncomms15484 High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED Does this really challange QED? Or does this mean that we miss certain contributions to QED calculations? The authors are speculating "new effects might appear in the interaction of the electron with itself, the vacuum or the nuclear fields in this regime, that is, the hyperfine interaction might be affected by the existence of new particles not included yet in the current standard model and therefore not considered in state-of-the-art QED calculations." Does this mean "new physics" or just standard model effects not taken into account so far, e.g. heavier particles like Myon, tau, W, Z, ...?