I am trying to use second quatized operators in the Maple Physics package.  These operators obey the commutation relations:

[psiA(x1),psiB(x2)] = Dirac(x1-x2) and [psiA(x1),psiC(x2)] = 0 for example.  The commutator therefore depends on the arguments of the operators.

Using:

> with(Physics);

> Setup(quantumoperators = {psiA,psiB,psiC},algebrarules={%Commutator(psiA(w),psiB(v)) = Dirac(w-v),%Commutator(psiA(w),psiC(v))=0})