The left and right chiral versions are related by a parity transformation. As shown below, these square to the Klein–Gordon operator only if η η = ζ ζ . The skew complex conjugate ω ω ψ ψ ∗ ∗ = i σ σ 2 ψ ψ can be recognized as the charge conjugate form of ψ ψ ; this is articulated in greater detail below. Thus, the Majorana equation can be read as an equation that connects a spinor to its charge-conjugate form.