EntityQ662636· pop 13· linked from 111 articlesnegative energySign in to saveconcept in physicsConnectionsquantum field theoryEntityvirtual particleEntityKilling vector fieldEntityphysicsEntityuniverseEntitygravityEntitymassEntityInternational Standard Book NumberEntitymatterEntityvacuumEntityclassical mechanicsEntitygeneral relativityEntityPaul DiracEntitypressureEntityconservation of energyEntitydigital object identifierEntityspacetimeEntitykinetic energyEntitydark matterEntityNewton's law of universal gravitationEntityCategoriesEnergy (physics)