Effects of Quenching in \Delta I=1/2 Kaon Decays

TL;DR

This paper investigates the limitations of quenched QCD in describing /2 kaon decays, highlighting how non-unitarity affects the extraction of physical matrix elements using chiral perturbation theory.

Contribution

It analyzes the inconsistencies caused by quenched approximation in /2 kaon decay calculations with one-loop chiral perturbation theory, emphasizing the invalidity of standard extraction methods.

Findings

Quenched QCD lacks unitarity, leading to invalid matrix element extraction.

Standard correlation function methods are unreliable in quenched approximation.

Inconsistencies arise in /2 kaon decay calculations due to quenching effects.

Abstract

We present the inconsistencies which arise in quenched QCD in $\Delta I=1/2$ non-leptonic kaon decays using chiral perturbation theory (ChPT) to one loop. In particular we discuss how the lack of unitarity of the quenched theory invalidates the usual methods for the extraction of matrix elements from correlation functions.