Parity-odd terms in the trace anomaly of Weyl fermions: elusive or delusive?
Date: 27 JUNE 2023 from 15:00 to 16:00
Event location: Sala IR-2A
The quantum breaking of classical symmetries leads to several intriguing phenomena. In particular, the breaking of Weyl invariance (local scale invariance) may have played a role in the early universe. In this talk, I will first recall some generalities of (Weyl) anomalies. Afterwards, I will slowly move on to the particularities that arise in the case of Weyl fermions, whose Weyl anomaly has been the source of much recent discussion. The term in
question is proportional to the Pontryagin density, multiplied by an imaginary factor of dangerous astrophysical implications. To conclude, I will present the arguments of those who claim that the odd term does exist, as well as the replies of those of us who asseverate the opposite. Based on 2304.08939 and 2101.11382.