Speaker
Description
A very popular choice for the fermion action used in lattice computations is the well-known $\mathcal{O}(a)$-improved Wilson action, which has been successfully employed in a wide range of applications. However, experience with this action has also revealed some of its limitations, such as the presence of small and even negative eigenvalues of the lattice Dirac operator due to the breaking of chiral symmetry, and discretization effects that have been observed to be larger than those of other actions for some quantities. In this talk, I will discuss some modifications to the action aimed at addressing these issues, namely the use of smearing, an exponentiated clover term, and the inclusion of a dimension-six operator to remove $\mathcal{O}(a^2)$ effects at tree level. I will also show how each of these modifications individually contributes to reducing discretization effects and the breaking of chiral symmetry.