לוח שנה משולב

It was recently understood that when QCD, or any vectorlike or chiral gauge theory, is compactified on a small circle, the physics responsible for confinement becomes analytically tractable by using new methods, such as twisted partition function or center-stabilizing double-trace deformations.
I will first give a qualitative review of the key points - some old and some recent -- the Polyakov mechanism of confinement, the twisted ``monopole-instantons" in circle compactifications (first discovered via string theory D-branes), and perhaps most importantly an index theorem by Nye and Singer (rederived by Poppitz et.al.). I will then argue that these ingredients give a new and quantitative description of confinement via novel non-self-dual topological excitations. These can be magnetic ``bions", ``triplets", ``quintets", etc., depending on the massless fermion content of the theory, somewhat at odds with conventional wisdom associating confinement with pure glue only. While the semi-classical solvability at small circle size does not apply to
QCD in the decompactification limit, it allows for qualitative studies of the phase diagram of any theory with massless fermions. In particular, it helps address the question of when a theory ceases to confine and becomes conformal upon adding extra massless fermionic species. Our predictions for the ``conformal window" in QCD and other vectorlike or chiral gauge theories will be compared to those obtained by lattice simulations and other tools.

The $mathcal{N}=4$ conformal supersymmetry exhibits a very simple sub-sector described by 4 differential operators whose commutation relations show the existence of an off-shell closed subalgebra contained in the superconformal algebra with 32 generators. The invariance under the symmetry described by subalgebra is big enough to determine the theory. This isrelated to the oxydation of new extended superalgebra in 1 dimensions.

The core circadian clock in zebrafish is similar to that described in mammals. Nevertheless, there are some notable features that render the zebrafish an attractive model for chronobiologists 1) Circadian rhythms appear early in life; rhythms of melatonin production in the pineal gland begin two days after fertilization. 2) Zebrafish peripheral clock-containing structures and cell lines are directly light-entrainable. 3) The zebrafish model offers a plethora of molecular-genetics techniques, such as gene knockdown and over expression, transgenesis, genome-wide transcriptome analysis (gene chip) and bioinformatics tools, including the entire genomic sequence.
Studies in our lab have indicated that circadian rhythms of pineal aanat2 expression appear on the third day of development and that light exposure is mandatory for the development of this rhythm. Additionally, light induces the expression of period2 (per2) in the pineal gland; an important event in the development of the pineal circadian clock. Utilization of the light-entrainable zebrafish cell lines enables to study the mechanisms underlying light-induced per2 expression and light-entrainment. These cell-based studies are being complimented by in vivo studies in wild type and per2:EGFP transgenic zebrafish line, where gene knockdown and over expression are used to determine the involvement of putative transcription factors in this process. Further, a genome-wide examination of gene expression allows the detection of known and novel rhythmic and light-induced genes, and their function in the pineal gland can be investigated in vivo by current molecular-genetic techniques. In conclusion, the use of zebrafish advances our understanding of the mechanisms underlying clock function, light-entrainment and functional development of the pineal gland.

Electronic states with unusual properties can be promoted at interfaces between complex oxides [1,2]. A particularly fascinating system is the interface between the band insulators LaAlO3 and SrTiO3, which displays conductivity with high mobility and 2D superconductivity [3-5].
In this presentation, field effect experiments performed on this system will be discussed. Using the electrostatic tuning of the carrier density, the phase diagram of the system has been explored, revealing a quantum phase transition (QPT) separating a 2D superconducting state from an insulating state [6]. The insulating phase displays signatures of weak localization. A detailed analysis of the electronic properties in the normal state across the phase diagram will be presented, revealing the presence of a strong spin-orbit coupling [7].