Speaker
Giovanna Paola Perdona'
(Istituto Nazionale di Fisica Nucleare)
Description
It is well known that the CP-violating phase $\theta_{EW}$ in the electroweak sector of the Standard Model (SM) is unphysical, as it can be removed by an anomalous B+L chiral rotation. It has recently been suggested that a parametrically light particle could exist in the spectrum, associated with the breaking of this B+L symmetry.
To determine whether such a light degree of freedom—denoted $\eta_{EW}$ exists within the Standard Model, one can perform explicit calculations of the topological susceptibility and of the B+Lbreaking condensate, along with a detailed analysis and comparison with the Schwinger model and QCD in the large-Nc limit.
Author
Giovanna Paola Perdona'
(Istituto Nazionale di Fisica Nucleare)