🌐EnglishEnglishDeutschEspañolItalianoPolskiTürkçeفارسی한국어中文日本語EntityQ1132926· pop 10· linked from 124 articlesOn shell and off shellconfigurations of a system that do or do not satisfy classical equations of motionAvailable in 10 languagesEspañolDeutsch中文日本語ItalianoCatalanPolskiفارسی한국어via Wikidata sitelinks · CC0ConnectionsphysicsEntityenergyEntityCategoriesQuantum field theory