Similarly, for any other Hermitian operator B ^ ^ in the same state σ σ B 2 = ⟨ ⟨ ( B ^ ^ − − ⟨ ⟨ B ^ ^ ⟩ ⟩ ) Ψ Ψ | ( B ^ ^ − − ⟨ ⟨ B ^ ^ ⟩ ⟩ ) Ψ Ψ ⟩ ⟩ = ⟨ ⟨ g ∣ ∣ g ⟩ ⟩ for | g ⟩ ⟩ = | ( B ^ ^ − − ⟨ ⟨ B ^ ^ ⟩ ⟩ ) Ψ Ψ ⟩ ⟩ .