QUANTUM FIELD THEORY
The famous double slit experiment used a set of single electrons (particles) fired one after the other through 2 slits. The result was an interference pattern which is characteristic of a wave and not a particle. This implied that each single electron would go through both slits; through no slits; through just the left slit and through just the right all at the same time!
Quantum field theory explains this by stating that matter is neither a wave nor a particle. It is something more abstract and could be considered as a simultaneous co-existence of all possibilities. Thi