I suppose you wanted to ask about unary operators. Unary operators accept one operand, in oppose to binary operators, which accept two. Examples to unary operators are: f(x) = -x f(x)= abs(x) f(x) = sin(x)
The hamiltonian operator is the observable corresponding to the total energy of the system. As with all observables it is given by a hermitian or self adjoint operator. This is true whether the...