Two objects with half spin would consist of the elementary particles (i.e. quarks, fermions etc.) which are waves. Therefore all objects consist of several waves. Waves can exist at the same place at the same time. Depending on whether the wave is at a trough or a crest and the amplitude, the waves either cancel each other out or amplify each other. Therefore why can’t objects exist at the same place at the same time, and just cancel or amplify each other depending on whether they are at a crescent or a trough?

**Answer**

1) Quantum mechanical waves are probability waves, i.e. *the probability* of finding a particle has a functional dependence on sines and cosines. It has nothing to do with amplitude as energy or momentum or whatever, the crescents and troughs are increased and decreased probabilities of being found when an observation is made.

2)Particles have spins. Particles that have integer spin are called bosons and *can* occupy the same space at the same time meaning the probability of finding one in an (x,y,z) coordinate increases the more of them there are. Bosons can occupy the same quantum state in general. Particles with half integer spin are fermions and follow the fermi-dirac statistics , and thus cannot occupy the same space; i.e the probability of finding one in an (x,y,z) spot will always be the probability for finding one particle; only one can occupy a quantum state at a time, in general.

**Attribution***Source : Link , Question Author : Community , Answer Author : anna v*