Boson half-integer spin particles cannot be bosons and integer spin particles cannot be fermions. In large systems, the difference between bosonic and fermionic statistics is only apparent at large densities — when their wave functions overlap. At low densities, both types of statistics are well approximated by Maxwell–Boltzmann statistics, which is described by classical mechanics. All observed elementary particles are either fermions or bosons. The observed elementary bosons are all gauge bosons: photons, W and Z bosons, gluons, except the Higgs boson which is a scalar boson. Finally, many approaches to quantum gravity postulate a force carrier for gravity, the graviton,
Superpartner Superpartner In particle physics, a superpartner (also sparticle) is a class of hypothetical elementary particles. Supersymmetry is one of the synergistic theories in current high-energy physics that predicts the existence of these "shadow" particles. When considering extensions of the Standard Model, the "s-" prefix from "sparticle" is used to form names of superpartners of the Standard Model fermions (sfermions), e.g. the stop squark. The superpartners of Standard Model bosons have an "-ino" (bosinos) appended to their name, e.g. gluino, the set of all gauge superpartners are called the gauginos. According to the supersymmetry theory, each fermion should have a partner