= Mostly-plus Dirac convention
{title2=$\eta=(-+++),\quad\{\gamma^a,\gamma^b\}=-2\eta^{ab}$}
One consistent <Dirac equation> convention uses $\eta=\operatorname{diag}(-1,1,1,1)$, $\{\gamma^a,\gamma^b\}=-2\eta^{ab}$, and $(i\gamma^a\partial_a+m)\psi=0$. Taking the negatives of the standard mostly-minus <gamma matrices>, and defining the <Dirac adjoint> with the new $\gamma^0$, gives the same physical <Dirac action>. The positive-frequency plane wave is $e^{ip\cdot x}u(p)$ with $p^0>0$, and its equation is $(\not p-m)u=0$. The <mass shell> is $p^2=-m^2$. These signs must be translated together when using a formula stated in another convention.
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