Polish physicists observe light-by-light scattering at CERN

Another important discovery was made with a significant contribution by Polish physicists conducting research at CERN within the ATLAS experiment using the Large Hadron Collider. For the first time ever, light-by-light scattering has been observed – a very rare phenomenon consisting in an interaction between two photons.

atlasPhoto: CERN

The paper published today in Nature Physics journal confirms one of the earliest assumptions of quantum electrodynamics.
Light-by-light scattering was observed by a team including researchers from the Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, physicists from the Polish Academy of Sciences Institute of Physics in Cracow, and German scientists from DESY research center in Hamburg and from the Johannes Gutenberg University of Mainz. Theoretical physicists from PAS Institute of Physics and other centers also played a crucial role in preparing the experiment. They suggested that the measurements should be carried out using the Large Hadron Collider.
“This is a milestone result: the first direct evidence of light interacting with itself at high energy,” says Dan Tovey, ATLAS Physics Coordinator. “This phenomenon is impossible in classical theories of electromagnetism; hence this result provides a sensitive test of our understanding of QED, the quantum theory of electromagnetism.”

The original CERN press release
The paper published in Nature Physics