Path-ordering

In theoretical physics, path-ordering is the procedure (or a meta-operator P {displaystyle {mathcal {P}}} ) that orders a product of operators according to the value of a chosen parameter: In theoretical physics, path-ordering is the procedure (or a meta-operator P {displaystyle {mathcal {P}}} ) that orders a product of operators according to the value of a chosen parameter: Here p is a permutation that orders the parameters by value: