TBA

TBA

After a brief introduction to the basic concepts of entanglement in discrete and continuous systems I will outline various results of our recent work in these areas. In particular, I will present a scaling relation for the entanglement of a subsystem with respect to the rest of the lattice in the size of the regions.

Based on the observation that classical strings only couple to area, we study the generalized geometry of manifolds equipped with an area measure but not a metric length measure. This in particular includes geometries combined from a metric and a two-form. We discuss the equation of stationary surfaces on these backgrounds which leads to the identification of differential geometric structures appropriate for area geometry. This work is expected to be of relevance for the study of the gravitational sector of strings and branes.

Evidence for the existence of some form of dark energy -- a smooth component that causes the accelerated expansion of the universe and contributes about 70 percent of the total energy density -- is by now very solid. However, very little progress has been made in understanding its nature and the underlying physical mechanism. In this talk I describe the prospects of several promising methods to improve the measurements of dark energy properties within the next decade. In addition to type Ia supernovae, these include weak gravitational lensing, counts of clusters of galaxies, and cosmic microwave background anisotropies. I comment on specific upcoming surveys, and challenges in controlling the systematic errors so that these probes can achieve their full potential and help us understand the nature of dark energy.

I review the structure of higher spin gauge theories in various dimensions, with some emphasize on the infinite-dimensional higher spin symmetries and unfolded dynamics approach. If I have time, I would also discuss how this approach works in the standard field theories like Yang-Mills and Einstein gravity.

One main reason to quantize gravity is the hope that the singularities of classical General Relativity will be absent within the framework of a quantum theory of gravity. One candidate for such a theory is the well developed framework of Loop Quantum Gravity. During the last years remarkable results concerning the big bang singularity have been achieved within symmetry reduced cosmological models of Loop Quantum Cosmology. In this talk we will address the question whether these results are characteristic also for the full, unreduced theory. As a first step towards answering that question we will present an explicit analysis of the geometric operator corresponding to the classical inverse scale factor occurring in cosmological models which has been performed within the full theory. The results will be discussed.

I will discuss the decay process of large-spin mesons in the context of the gauge-string duality, using generic properties of confining backgrounds and systems with flavour branes. In the string picture, meson decay corresponds to the quantum-mechanical process in which a string rotating on the IR wall. fluctuates, touches a flavour brane and splits into two smaller strings. This process automatically encodes flavour conservation as well as the Zweig rule. I will show that the decay width computed in the string picture is in remarkable agreement with the decay width obtained using the phenomenological Lund model.

The Kahler-Ricci flow provides a useful method of deforming any Kahler metric towards a caononical metric. In this talk, we will discuss on recent progress on the Kahler-Ricci flow and how the flow behaves on manifolds with positive Kodaira dimension and without Kahler-Einstein metrics.

Inspired by an old idea of von Neumann, we seek a pair of commuting operators X,P which are, in a specific sense, 'close' to the canonical non-commuting position and momentum operators, x,p. Difficulties with von Neumann's original idea (involving an alleged orthogonalization of the coherent states) are discussed. Here these difficulties are avoided by restricting attention to operators acting on density matrices which are reasonably decohered (i.e., spread out in phase space). Such operators could be of use in discussions of emergent classicality from quantum mechanics. Moreover, they may be used to give a discussion of the relationship between exact and approximate decoherence in the decoherent histories approach to quantum theory.

In this talk I will describe the phenomenology associated with neutrino oscillations and I will review the evidence for neutrino mass from solar and atmospheric neutrino experiments, as well as from the most important laboratory searches for neutrino oscillations. I will also briefly discuss the main implications for theory.