arXiv subjects

Vincenzo Branchina

Publications and source records attributed to Vincenzo Branchina.

39 records · Page 3Linked to original sources

arXiv1997

Instanton Induced Phenomena in the Effective Standard Model

It is shown that in the Effective Standard Model new phenomena can arise due to the presence of small instanton configurations. The chief result is that under certain conditions new hidden coupling constants could exist in the model. In the Electroweak sector that might result in the possibility of observing B+L violating processes due to a highly non perturbative contribution to the holy grail function. The same phenomenon might occur in the QCD sector of the theory and could be observed in the DIS experiments at HERA.

hep-ph↗

arXiv1996

Mini-Instantons in SU(2) Gauge Theory

The effects of instantons close to the cut-off is studied in four dimensional SU(2) gauge theory with higher order derivative terms in the action. It is found in the framework of the dilute instanton gas approximation that the convergence of the topological observables requires non-universal beta function.

hep-th↗

arXiv1994

Mini-Instantons

It is shown that the inhomogeneous saddle points of scale invariant theories make the semiclassical expansion sensitive on the choice of non-renormalizable operators. In particular, the instanton fugacity and the beta function of the two dimensional non-linear sigma model depends on apparently non-renormalizable operators. This represents a non-perturbative breakdown of that concept of universality which is based on low dimensional operators.

hep-th↗