Particle Physics

I argue that all necessary ingredients for successful inflation are present in the minimal supersymmetric standard model (MSSM). The potential for the supersymmetric flat directions (which can be viewed as moduli near points of enhanced symmetry) generically has metastable minima at large field values. An adjustment of soft supersymemtry breaking parameters results in a point where the first two derivatives of the potential vanish. One can then have more than 10^3 e-foldings of slow roll inflation with a Hubble rate ~ O(1-10) GeV in the vicinity of this point. The model has a robust prediction for the scalar spectral index: n_s \leq 0.93, which agrees with the current WMAP and LSS data within 2\sigma. It can be implemented purely within MSSM, or MSSM plus Dirac neutrinos. It has the unique feature of having a concrete and real connection to physics that can be observed in earthbound laboratories.

At low energy and small curvature, general relativity has the form of an effective field theory. I will describe the structure of the effective field theory, and show how it can be used to calculate low energy quantum effects.

Neutrinos are the big unknown in Particle Physics. Since their very beginning they behaved strangely. However, in the last decade experiments were able to solve some of their secrets. The talk will review the current experimental status of neutrino experiments and give an outlook on future activities.

Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature produces protons and photons with energies in excess of 1020 and1013 electronvolts, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. The problem has been to develop a robust and affordable technology to build the kilometer-scale neutrino detectors required to do the science. The AMANDA telescope using clear deep Antarctic ice as a Cherenkov detector of muons and showers initiated by neutrinos of all 3 flavors, has met this challenge. We review the results obtained with more than 10,000 well-reconstructed neutrinos in the 50 GeV~500 TeV energy range collected during its first 5 years of operation. More importantly, we will show that AMANDA represents a proof of concept for the ultimate kilometer-scale neutrino observatory, IceCube, now under construction.