Identical particles, also called
indistinguishable or
indiscernible particles, are
particles that cannot be distinguished from one another, even in principle. Species of identical particles include, but are not limited to
elementary particles such as
electrons, composite
subatomic particles such as
atomic nuclei, as well as
atoms and
molecules.
Quasiparticles also behave in this way. Although all known indistinguishable particles are
"tiny", there is no exhaustive list of all possible sorts of particles nor a clear-cut limit of applicability; see particle statistics #Quantum statistics for detailed explication.