“Something happened:” on the real, the actual, and the virtual in elementary particle physics

Throughout the history of quantum theory, “an elementary particle” has been a problem to which only fragments of a possible solution could be offered. At a certain point of this history, “a virtual particle” has become part of this problem. While still considering this problem as a problem, this article, in contrast to most approaches to it, which are realist in nature, offers a nonrealist one. This approach is grounded in the concept of reality without realism, RWR, introduced by this author previously, and an interpretation of high-energy quantum phenomena and quantum field theory (QFT), grounded in this concept, which allows for a range of (RWR-type) interpretations. The status of real and virtual particles is different in the present interpretation. While, in this interpretation, both concepts are idealizations, that of real particles is required by it. By contrast, the concept of virtual particles is not required, although, because of certain observable effects in high-energy quantum regimes, this interpretation assumes that there exists something in nature, especially manifested in high-energy quantum regimes, that may be handled by means of the concept of virtual particles. RWR-type interpretations do, however, permit an idealization defined by this concept and may adopt it, because of its practical effectiveness. This article will do so, while still maintaining the essential difference in the nature of the idealizations defined by the concepts of real and virtual particles