In mathematics and theoretical physics, braid statistics is a generalization of the spin statistics of bosons and fermions based on the concept of braid group.
under such exchange [1][2] or even a non-trivial unitary transformation in the Hilbert space (see non-Abelian anyons).
A similar notion exists using a loop braid group.
Braid statistics are applicable to theoretical particles such as the two-dimensional anyons and plektons.
It obeys the causality rules of algebraic quantum field theory, where only observable quantities need to commute at spacelike separation, where anyons follow the stronger rules of traditional quantum field theory; this leads, for example, to (2+1)D anyons being massless.