Global symmetry-breaking and generalized theta-terms in Type IIB EFTs

Understand

A longstanding conjecture states that global symmetries should be absent in quantum gravity.

• By investigating large classes of Type IIB four-dimensional $\mathcal{N}=2$ effective field theories, we enlist the potential generalized global symmetries that could be present and explore how they are avoided.
• Crucial ingredients that arise in such effective field theories are generalized $\theta$-terms.
• These introduce non-linear couplings between axion fields and topological terms quadratic in the gauge field strengths which break a large subset of the global symmetries.