Let $I$ be the action of some QFT (gauge-fixed and including all the necessary counter-terms); $S$ the associated scattering-matrix; and $Z$ the partition function (in the form of, say, a path integral). There are three notions of symmetries that are typically discussed,
- Action symmetries, that is, transformations of the form $\phi\to\phi'$ that leave $I$ invariant,
- $S$-matrix symmetries, that is, operators that (super)commute with $S$, and
- Quantum symmetries, that is, transformations of the form $\phi\to\phi'$ that leave the volume form $\mathrm e^{I[\phi]}\mathrm d\phi$ invariant.
It is a well-known phenomenon that the symmetries of $I$ need not agree with those of neither $S$ nor $Z$ (e.g., anomalies, SSB, etc.). What is not-so-clear is whether $S$ symmetries and $Z$ symmetries are equivalent. What I want to know is whether
For each symmetry of $S$ there is a symmetry of $Z$ and vice-versa
or a counter-example. If the equivalence is actually true, I would like to have a more-or-less precise statement, in the form of a theorem (to the usual level of rigour in physics textbooks).
No cheating please. Counter-examples are only valid for "real-life" QFT's (e.g. in a free theory everything commutes with $S$ but not everything leaves $Z$ invariant; this is not a valid counter-example because it is completely trivial). No TQFT's either. Thanks.
Someone mentioned in the comments the effective action $\Gamma[\phi]$, which is defined as the Legendre transform of $\log Z$. I didn't want to bring this object into the picture, because I wanted to leave it to the discretion of the rest of users whether to mention this object or not. In principle, I don't need answers to analyse the symmetries of this object, but they may if they believe it could be useful to do so. In any case, let me stress that $\Gamma$ is not the same object as $I$.