Ponente
Descripción
We propose an efficient method to perform on-shell matching calculations in effective field theories. The standard off-shell approach to matching requires the use of a Green's basis that includes redundant and evanescent operators. The reduction of such a basis to a physical one is often highly non-trivial, difficult to automate and error prone. However, on-shell matching allows to perform the matching directly to the physical basis, thus overcoming the necessity to deal with redundancies and evanescent operators.
Our proposal is based on a numerical solution of the corresponding on-shell matching equations, which automatically implements in a trivial way the delicate cancellation of non-local terms between the full theory and the effective one. The use of rational on-shell kinematics ensures an exact analytic solution despite the numerical procedure. In contrast to the traditional off-shell matching, where one has to match only one-light-particle irreducible Green functions, with this approach the full amplitude is needed. In this way we only need a physical basis to perform the matching. We present the algorithm and some further applications in which the on-shell matching approach can be very useful, such as the automation of the Green’s basis reduction to a physical one, the obtaining of evanescent contributions or the computation of renormalization group equations.
Abstract
We propose an efficient method to perform on-shell matching calculations in effective field theories. The standard off-shell approach to matching requires the use of a Green's basis that includes redundant and evanescent operators. The reduction of such a basis to a physical one is often highly non-trivial, difficult to automate and error prone. However, on-shell matching allows to perform the matching directly to the physical basis, thus overcoming the necessity to deal with redundancies and evanescent operators.
Our proposal is based on a numerical solution of the corresponding on-shell matching equations, which automatically implements in a trivial way the delicate cancellation of non-local terms between the full theory and the effective one. The use of rational on-shell kinematics ensures an exact analytic solution despite the numerical procedure. In contrast to the traditional off-shell matching, where one has to match only one-light-particle irreducible Green functions, with this approach the full amplitude is needed. In this way we only need a physical basis to perform the matching. We present the algorithm and some further applications in which the on-shell matching approach can be very useful, such as the automation of the Green’s basis reduction to a physical one, the obtaining of evanescent contributions or the computation of renormalization group equations.
