Speaker
Description
During the last decade, the notion of an 't Hooft anomaly has
been generalised to the case of discrete symmetries. An interesting
instance, discussed by Tanizaki, is the mixed anomaly between the
discrete axial symmetry and the flavour and baryonic symmetries in
massless QCD. The goal of this talk is to provide a derivation of this
anomaly from a top-down holographic dual of QCD. I will show that the
topological couplings in the bulk supergravity dual of the D4-D8 system
encode Tanizaki's anomaly, once fluctuations around the bulk gauge
fields are turned on. A technical challenge for this computation is the
difficulty in maintaining gauge invariance of supergravity theories in
the presence of D-branes. To overcome this issue, a compact formulation
of the flux sector of (massive) type IIA supergravity in the presence of
D8 branes is presented.