Instantons and fixed-point actions in SU(2) gauge theory Original Research Article

We describe the properties of instantons in lattice gauge theory when the action is a fixed-point action of some renormalization group transformation. We present a theoretically consistent method for measuring topological charge using an inverse renormalization group transformation. We show that, using a fixed-point action, the action of smooth configurations with non-zero topological charge is greater than or equal to its continuum value 8π2/π2.