This series consists of talks in the areas of Cosmology, Gravitation and Particle Physics.
We express the total equation of state parameter of a spatially flat Friedman-Robertson-Walker universe in terms of derivatives of the red-shift dependent spin-weighted angular moments of the two-point correlation function of the three dimensional cosmic shear. In the talk I will explain all the technical terms in the first sentence, I will explain how such an expression is obtained and highlight its relevance for determining the expansion history of the universe.
The recently released WMAP 3-year data on the anisotropy and polarization of the Cosmic Microwave Background is a milestone in cosmology. For the first time, it is possible to rule out popular models of inflation in the early universe. However, the WMAP3 data contain interesting hints which indicate that it may be too early to declare a "slam dunk" for simple single-field models of inflation.
I will discuss phenomenological aspects on N=1, four-dimensional Type IIB string theory compactifications with all moduli stabilised. In particular, I will review a class of compactifications with exponentially large volumes of the Calabi-Yau manifold and derive explicit formulae for bulk and D3/D7 moduli masses. Then I will show what patterns of soft supersymmetry breaking terms can arise after renormalisation group running to the weak scale.
The discovery of cosmic acceleration has generated tremendous excitement among researchers in fundamental physics and cosmology. Most experts agree that nothing short of a revolution will be required to fully integrate the observed cosmic acceleration (which many attribute to a mysterious "dark energy") with established physics. Currently this discovery is driving very exciting research in both the theoretical and observational domain.
From the Quantum Field Theory point of view, matter and gauge fields are generally expected to be localised around branes (topological defects) occurring in extra dimensions. I will discuss a simple scenario where, by starting with a five dimensional SU(3) gauge theory, we end up with several 4-D parallel braneworlds with localised 'chiral' fermions and gauge fields to them. I will show that it is possible to reproduce the electroweak model confined to a single brane, allowing a simple and geometrical approach to the hierarchy problem.