Chiral-Symmetry and Strange Four-Quark Matrix Elements

Abstract

We consider the matrix elements of the left-handed flavor-conserving four-quark operators in the nucleon and pion states. Using chiral symmetry, we derive relationships among these matrix elements. We argue that the $\Delta I=1/2$ rule of hyperon and kaon non-leptonic weak decay implies possible large strange-quark content in the nucleon and pion.

Comments: 10 pages in Plain TeX, MIT CTP #2188