The formation and development of the concept of virtual particles

• Applicants: Professor Dr. Robert Harlander; Dr. Adrian Wüthrich
• Subject Area: Theoretical Philosophy ; History of Science
• Term: from 2016 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234743567

This project investigates the concept of a virtual particle from the viewpoint of the history and philosophy of science ("integrated HPS"). This concept is an integral part of modern physics, mainly since it provides a means to describe and interpret complex quantum physical processes in comparatively simple terms. Despite its wide use, the notion of a virtual particle appears not to be clearly defined. The present project traces the origins of the concept and follows its evolution through time. Phase 1 investigated systematically the reasons for the introduction of the concept in quantum mechanics and early quantum field theory (QFT). Phase 2 will focus on the further development of the concept in the context of QFT, S-matrix theory, and the Standard Model. In this phase we also aim to explain the genesis of today’s diverse uses of the term and, taking into account the results from the previous phase, to further our general understanding of concept formation in the physical sciences.

• DFG Programme: Research Units
• Subproject of: FOR 2063: The Epistemology of the Large Hadron Collider
• Co-Investigator: Professor Dr. Friedrich Steinle