This series consists of talks in the areas of Particle Physics, High Energy Physics & Quantum Field Theory.
The observed conservation of Baryon and Lepton number may arise because they are gauge symmetries. Models are discussed where Baryon and lepton number are the charges for a spontaneously broken U(1) gauge symmetries. The best of these models is: (1) free of Landau poles that are near the weak scale, (2) has no flavor changing neutral currents at tree level and (3) contains a dark matter candidate.
Recently, several neutrino physics has witnessed an accumulation of anomalous results. In the first part of this talk, we will discuss the tension that the MINOS experiments has seen between oscillations of neutrinos and anti-neutrinos. We will show that, phenomenologically, this tension can be explained if neutrinos are hypothesized to have new interactions mediated by higher-dimensional operators, but we will also show that problems arise when one attempts to embed these operators into renormalizable models.
Unexplained hierarchies and the quest for naturalness have driven model-building efforts in particle physics and cosmology for the past few decades. I will speak about various approaches to problems of 'unnatural'
fine tunings, in the context of supersymmetry, inflation and LHC phenomenology respectively.
It is often assumed that the first evidence for direct dark matter detection will come from experiments probing spin-independent interactions, because of higher sensitivities due to coherence effects. We explore the possibility of models that would be invisible in such experiments, but detectable via spin-dependent interactions. The existence of much larger (or only) spin-dependent tree-level interactions is not sufficient, due to potential spin-independent subdominant or loop-induced interactions.
After quickly reviewing what we have learned about neutrinos during the past decade, I present an overview of different mechanisms responsible for non-zero neutrino masses, also discussing the possibility of experimentally deciding which one, if any, is correct.
Using the framework of deconstruction, we construct simple, weakly-coupled supersymmetric models that explain the Standard Model flavor hierarchy and produce a flavorful soft spectrum compatible with precision limits. Electroweak symmetry breaking is fully natural/ the mu-term is dynamically generated with no B mu-problem and the Higgs mass is easily raised above LEP limits without reliance on large radiative corrections.
Neutrino oscillations has been observed and confirmed at two mass splittings (\Delta m^2), which is consistent with three generations of neutrinos and an unitary mixing matrix. Despite the rapid progress in understanding neutrino oscillations in the last decade, two large questions remain about neutrino oscillation parameters at \Delta m^2 ~ 0.001 eV^2. Is \theta_{23} exactly 45 degrees, indicating an additional symmetry in neutrino mixing? Is \theta_{13} non-zero, which would mean there could be CP violation in the neutrino sector.
TBA
We calculate scalar quantum fluctuations during inflation in the presence of a black hole. The implications to the cosmic microwave background anisotropy are briefly mentioned.
On small scales the cosmic microwave background (CMB) is perturbed by large scale structure in the universe, primarily through Compton scattering and gravitational lensing. The current generation of CMB experiments is measuring these signals, allowing new measurements of the build-up of cosmic structure.