Anatomy of a weak matrix element

Anatomy of a Weak Matrix Element

Although the weak nonleptonic amplitudes of the Standard Model are notoriously difficult to calculate, we have produced a modified weak matrix element which can be analyzed using reliable methods. This hypothetical nonleptonic matrix element is expressible in terms of the isovector vector and axialvector spectral functions ρV(s) and ρA(s), which can be determined in terms of data from tau lepto...

On Nonlinear Preservers of Weak Matrix Majorization

Arens Regularity and Weak Amenability of Certain Matrix Algebras

Motivated by an Arens regularity problem, we introduce the concepts of matrix Banach space and matrix Banach algebra. The notion of matrix normed space in the sense of Ruan is a special case of our matrix normed system. A matrix Banach algebra is a matrix Banach space with a completely contractive multiplication. We study the structure of matrix Banach spaces and matrix Banach algebras. Then we...

on nonlinear preservers of weak matrix majorization

Calculation of a weak nonleptonic matrix element using “Weinberg” sum rules

There is a “toy” weak matrix element which can be expressed as an integral over the vector and axial vector spectral functions, ρV (s)− ρA(s). I review our recent evaluation of these spectral functions, the study of four “Weinberg” sum rules and the calculation of this matrix element. [Talk presented at the XXVIII International Conference on High Energy Physics, ICHEP94, Glasgow, Aug. 1994, to ...