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arXiv · hep-ph/9409402

General Effective Actions

Eric D'Hoker·Steven Weinberg
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Abstract

We investigate the structure of the most general actions with symmetry group $G$, spontaneously broken down to a subgroup $H$. We show that the only possible terms in the Lagrangian density that, although not $G$-invariant, yield $G$-invariant terms in the action, are in one to one correspondence with the generators of the fifth cohomology classes. For the special case of $G=SU(N)_L \times SU(N)_R$ broken down to the diagonal subgroup $H=SU(N)_V$, there is just one such term for $N\geq 3$, which for $N=3$ is the original Wess-Zumino-Witten term.

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Eric D'Hoker, Steven Weinberg. 1994-09-23. General Effective Actions. https://doi.org/10.1103/physrevd.50.r6050

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