Quantum Mechanics, at atomic and sub-atomic levels deal with the study of how particles at this level behave and how the matter and energy interacts.
It also explains the properties of atoms, molecules and the particles constituting these.
The wave- particle duality of quantum mechanics that says that matter or every quantum of it exhibits wave as well as particle nature.
This theory was incorporated with its mathematical description given by Schrodinger was also incorporated in the theory for eave-particle duality and The probability for the existence of particle was determined.