  We study quantum many-body states of immanons, hypothetical particles that
obey an exchange symmetry defined for more than two participating particles.
Immanons thereby generalize bosons and fermions, which are defined by their
behavior under pairwise symmetric and anti-symmetric exchange processes. The
scalar product of two many-body states with fermionic, bosonic or generalized
exchange symmetry becomes the determinant, permanent or immanant of the matrix
containing all mutual scalar products of the occupied single-particle states.
As a measurable consequence, immanons are shown to obey a partial Pauli
principle that forbids the multiple occupation of single-particle states above
a certain threshold. The tendency to favor or oppose multiple occupation of
single-particle modes, i.e. the degree of bunching, is the determinant,
permanent or immanant of a hermitian positive semi-definite matrix. We exploit
this identity to devise a Gedankenexperiment that corroborates the permanental
dominance conjecture.
