🌐EnglishEnglishBahasa IndonesiaDeutschEspañolFrançaisItalianoPortuguêsTürkçeРусскийالعربيةفارسی한국어中文日本語EntityQ6987233· pop 20· linked from 200 articlesnegative massAlso known as negative matterhypothetical type of exotic matter whose mass is of opposite sign to the mass of normal matterAvailable in 19 languagesEspañolFrançais中文日本語РусскийItalianoالعربيةBahasa IndonesiaBanglaCatalanChuvashConnectionsmassEntitygravityEntityCategoriesExotic matterGravityHypotheses in physicsMassWarp drive theoryWormhole theory