Consider the Hamiltonian H=Z⊗3 acting on 3 qubits.
What is the ground energy of the system? (I.e. the lowest eigenvalue of H?)
What is the dimension of the ground energy subspace? (I.e. multiplicity of that eigenvalue?)
What is the ground energy of the system? (I.e. the lowest eigenvalue of H?)
What is the dimension of the ground energy subspace? (I.e. multiplicity of that eigenvalue?)