Mirror Symmetry p.188
Eq. 10.109 states that $$H \left\vert \alpha\right> = 0 \Longleftrightarrow Q \left\vert\alpha\right> = \overline{Q} \left\vert\alpha\right> =0. \tag{10.109}$$ I dont see why this is true, should not just $$Q\overline{Q}\left\vert \alpha\right> = - \overline{Q} Q \left\vert \alpha\right>$$ be true?