Star-Product Formalism for the Probability and Mean-Value Representations of Qudits

We develop the quantizer–dequantizer formalism for the probability and mean-value representations of qubits and qutrits. In these representations, the elements of symbols of operators are measurable physical quantities. We derive the star-product kernels, which lead to explicit expressions of the associative product of the symbols of the density operators and quantum observables for qubits. The extension of the quantizer–dequantizer formalism associated with the probability and mean-value descriptions of qudit states is discussed.