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  1. Eqs. (1) & (2) are the standard way a Noether charge $Q$ generates a symmetry transformation, cf. e.g. this & this related Phys.SE posts.

    More generally, an operator $\hat{F}$ is transformed as $$\begin{align}\hat{F}~\longrightarrow~e^{\epsilon\hat{Q}}\hat{F}e^{-\epsilon\hat{Q}}~=~&e^{[\epsilon\hat{Q},~\cdot~]_{C}}\hat{F}\cr ~=~&e^{\epsilon[\hat{Q},~\cdot~]_{SC}}\hat{F}\cr ~=~&\hat{F}+\epsilon[\hat{Q},\hat{F}]_{SC}+{\cal O}(\epsilon^2),\end{align}\tag{A}$$ where $[\cdot,\cdot]_{C}$ and $[\cdot,\cdot]_{SC}$ are the commutator and supercommutator, respectively. In eq. (A) we have assumed that $\hat{Q}$ and $\epsilon$ carry the same Grassmann parity.

    See also e.g. this related Phys.SE post.

  2. In case of the BRST symmetryBRST symmetry, the charge $Q$ is Grassmann-odd, so in.

    In terms of value, ita Grassmann-odd charge $Q$ is either zero orsoul-valued, i.e. a definite non-zero value does not make sense, cf. e.g. this related Phys.SE post.

  1. Eqs. (1) & (2) are the standard way a Noether charge $Q$ generates a symmetry transformation, cf. e.g. this & this related Phys.SE posts.

  2. In case of the BRST symmetry, the charge $Q$ is Grassmann-odd, so in terms of value, it is either zero or non-zero, cf. e.g. this related Phys.SE post.

  1. Eqs. (1) & (2) are the standard way a Noether charge $Q$ generates a symmetry transformation, cf. e.g. this & this related Phys.SE posts.

    More generally, an operator $\hat{F}$ is transformed as $$\begin{align}\hat{F}~\longrightarrow~e^{\epsilon\hat{Q}}\hat{F}e^{-\epsilon\hat{Q}}~=~&e^{[\epsilon\hat{Q},~\cdot~]_{C}}\hat{F}\cr ~=~&e^{\epsilon[\hat{Q},~\cdot~]_{SC}}\hat{F}\cr ~=~&\hat{F}+\epsilon[\hat{Q},\hat{F}]_{SC}+{\cal O}(\epsilon^2),\end{align}\tag{A}$$ where $[\cdot,\cdot]_{C}$ and $[\cdot,\cdot]_{SC}$ are the commutator and supercommutator, respectively. In eq. (A) we have assumed that $\hat{Q}$ and $\epsilon$ carry the same Grassmann parity.

    See also e.g. this related Phys.SE post.

  2. In case of the BRST symmetry, the charge $Q$ is Grassmann-odd.

    In terms of value, a Grassmann-odd charge $Q$ is soul-valued, i.e. a definite non-zero value does not make sense, cf. e.g. this related Phys.SE post.

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Qmechanic
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  • 590
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  1. Eqs. (1) & (2) are the standard way a Noether charge $Q$ generates a symmetry transformation, cf. e.g. this & this related Phys.SE posts.

  2. In case of the BRST symmetry, the charge $Q$ is Grassmann-odd, so in terms of value, it is either zero or non-zero, cf. e.g. this related Phys.SE post.