Discrepancies in quantum electro-dynamics

Abstract

Experimental tests of quantum electro-dynamics (QED) have developed dramatically for simple atomic systems such as hydrogen. However, a range of anomalies has been discovered recently. There has also been significant progress for medium-Z hydrogenic and helium-like atoms. In this area tests are often based on X-ray spectroscopic measurements. Future prospects for critical insight into the nature and convergence of QED in multi-electron systems will be discussed. © 2004 Elsevier Ltd. All rights reserved.