Séminaire de physique théorique par
Mauro PAPINUTO, INFN Rome
In order to test the hadronic sector of the standard model and extract the values of CKM parameters, it is important to provide a reliable theoretical prediction of the relevant week matrix elements.
I will discuss some issues concerning the computation by means of QCD simulations on the lattice, of Delta S = 2 and Delta B = 2 matrix elements relevant to extract informations from experimentally measured quantities. Moreover, by considering the whole basis of four fermiion operators appearing in the most general Delta F = 2 effective hamiltonian, predictions can be otained for any model of new physics where the new contributions with respect to the standard model originate from extra heavy particles.