- #1

- 288

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\begin{array}{cc}

\psi_{+}(\mathbf{x}) \\

\psi_{-}(\mathbf{x})

\end{array}

\right)=\left(

\begin{array}{cc}

\psi_{+}(\mathbf{-x}) \\

\psi_{-}(\mathbf{-x})

\end{array}

\right).[/tex] It's elementary to show that if a state has orbital angular momentum [itex]l[/itex], then its parity is [itex](-1)^l[/itex].

But apparently some particles - specifically the antiparticles of fermions - have some sort of "intrinsic parity" equal to [itex]-1[/itex], which means that [tex]P \left(

\begin{array}{cc}

\psi_{+}(\mathbf{x}) \\

\psi_{-}(\mathbf{x})

\end{array}

\right)=-\left(

\begin{array}{cc}

\psi_{+}(\mathbf{-x}) \\

\psi_{-}(\mathbf{-x})

\end{array}

\right).[/tex]

How is this possible? Where does that extra factor of [itex]-1[/itex] come from?