Neutron Majorana mass from Exotic Instantons in a Pati-Salam model

Understand

We show how exotic stringy instantons can generate an effective interaction between color diquark sextets in a Pati-Salam model, inducing a Majorana mass term for the neutron.

• In particular, we discuss a simple quiver theory for a Pati-Salam like model, as an example in which the calculations of exotic instantons' effects are simple and controllable.
• We discuss some different possibilities in order to generate $n-\bar{n}$ oscillation testable in the next generation of experiments, Majorana mass matrices for neutrini and a Post-Sphaleron Baryogenesis scenario.
• Connections with Dark Matter issues and the Higgs mass Hierarchy problem are discussed, in view of implications for LHC and rare processes physics.