General Formulation for Proton Decay Rate in Minimal Supersymmetric SO(10) GUT

We make an explicit formulation for the proton decay rate in the minimal renormalizable supersymmetric (SUSY) SO(10) model. In this model, the Higgs fields consist of ${\bf 10}$ and ${\bf \bar{126}}$ SO(10) representations in the Yukawa interactions with matter and of ${\bf 10}$, ${\bf \bar{126}}$, ${\bf 126}$, and ${\bf 210}$ representations in the Higgs potential. We present all the mass matrices for the Higgs fields contained in this minimal SUSY SO(10) model. Finally, we discuss the threshold effects of these Higgs fields on the gauge coupling unification.Comment: 32 pages, typos are corrected, a few references and comments to the papers arXiv:hep-ph/0204097 and arXiv:hep-ph/0402122 are adde

Improving Sweden's Automatic Pension Adjustment Mechanism

The public pension world has seen two innovations in recent years. One is the emergence of notional defined contribution (NDC) plans. The other is the introduction of automatic adjustment mechanisms to help keep pension systems solvent when the economy weakens. This brief looks at the Swedish system to demonstrate how NDCs work and evaluates the work­ings of the automatic adjustment mechanism in the wake of the 2008 financial crisis. Sweden passed reform legislation in 1994 that in­troduced a partially-funded NDC plan.1 The arrange­ment is conceptually similar to a defined contribution plan in that contributions are accumulated in indi­vidual accounts, but different in that the accounts are not fully funded and may be financed entirely on a pay-as-you-go basis. In this setting, the rate of return credited on the account assets is based on a rule rath­er than on actual returns. The Swedish system uses a notional interest rate equal to the rate of growth of average earnings. However, if a calculation suggests a potential deficit, the notional interest rate is auto­matically reduced through a “brake” mechanism. The recent financial crisis has highlighted ways in which the brake mechanism could be improved. This brief proceeds as follows. The first section describes Sweden’s NDC plan. The second describes the Swedish brake mechanism. The third describes two problems with the current adjustment procedure: 1) it creates the likelihood of large shocks for retir­ees; and 2) while disadvantaging retirees, it tends to advantage workers. The fourth section presents pos­sible fixes for the current problems. The final section concludes that the Swedish NDC plan could function more effectively with modest changes to the brake mechanism.