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mutual_information(state, base=2)

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Calculate the mutual information of a bipartite state.

The mutual information II is given by:

I(ρAB)=S(ρA)+S(ρB)S(ρAB)I(\rho_{AB}) = S(\rho_A) + S(\rho_B) - S(\rho_{AB})

where ρA=TrB[ρAB],ρB=TrA[ρAB]\rho_A=Tr_B[\rho_{AB}], \rho_B=Tr_A[\rho_{AB}], are the reduced density matrices of the bipartite state ρAB\rho_{AB}.



The mutual information I(ρAB)I(\rho_{AB}).

Return type



  • QiskitError – if the input state is not a valid QuantumState.
  • QiskitError – if input is not a bipartite QuantumState.
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