Speaker
Lena Funcke
(Perimeter Institute)
Description
The infamous strong CP problem in particle physics can in principle be solved by a massless up quark. In particular, it was hypothesized that topological effects could substantially contribute to the observed nonzero up-quark mass without reintroducing CP violation. Alternatively to previous work using fits to chiral perturbation theory, in this talk we present direct lattice QCD computations of the topological mass contribution, based on examining the dependence of the pion mass on the dynamical strange-quark mass. We find that the size of the topological mass contribution is inconsistent with the massless up-quark solution to the strong CP problem.
Primary authors
Constantia Alexandrou
(University of Cyprus and The Cyprus Institute)
Jacob Finkenrath
(The Cyprus Institute)
Lena Funcke
(Perimeter Institute)
Karl Jansen
(DESY Zeuthen)
Bartosz Kostrzewa
(University of Bonn)
Ferenc Pittler
(The Cyprus Institute)
Carsten Urbach
(University of Bonn)
