Next Seminar     » TBA        by Stefania Gori on Tuesday June 05th, 2012 at 14:00        [ more details ]

LPPC Prof. M. Shaposhnikov LPPC is working on the interplay between particle physics and Cosmology. Cosmology provides the key evidence that the canonical Standard Model (SM) of particle physics, although extremely successful in explaining existing accelerator data, is not a complete theory of Nature. In particular, it contradicts to the observed neutrino oscillations, does not provide a dark matter (DM) candidate, and gives no explanation for the observed excess of matter over anti-matter in the Universe. It also does not explain the present accelerated expansion of the Universe, and does not lead to primordial inflation. We take these facts as a guiding principle for the quest for a fundamental theory. Other directions of research of LPPC include various approaches to effective quantum theory of gravity, to the strong CP problem, the role of quantum anomalies in physics, phase transitions in gauge theories at high temperatures and their cosmological applications, model independent study of Dark Matter and structure formation in the Universe, the search for decaying Dark Matter.

LPTP Prof. R. Rattazzi What is the dynamics underlying electroweak symmetry breaking? Is it weak or is it strong? Does it entail new symmetry principles such as supersymmetry or conformal invariance? Is there a common principle underlying all fundamental interactions? How can we find a clue to those questions in the forthcoming LHC data? These are the basic questions driving research at LPTP.

GR-SC Prof. C. Scrucca The research activity of Claudio Scrucca concerns the quest for a more fundamental theoretical description of elementary particle physics, in which the known types of particles and forces are treated in a unified way and in a common framework. This consists in the theoretical investigation of new physical properties of particle dynamics that are postulated to emerge at high energies, like for instance supersymmetry, extra dimensions and strings. More precisely, his interests focus on the study of extensions of the standard model of particle physics motivated on one side by these new principles and on another side by the limitations plaguing the standard description. His main projects concern the characterization of the phenomenological and the cosmological constraints that can be put on supergravity models, which represent theoretically very compelling and phenomenologically viable candidates for an effective description of physics beyond the standard model in this paradigm of unification.

Lesgourgues Group Dr. J. Lesgourgues Julien Lesgourgues works on cosmology, the area of physics devoted to the understanding of our universe's global properties and evolution. This rapidly developing field is placed at the interface between theoretical physics, particle physics and astrophysics. The original background of Julien Lesgourgues is rather in theoretical physics, but he is getting closer and closer to astrophysics, with a particular interest for understanding and interpreting astrophysical observations relevant for cosmology. He is specialized in modeling the evolution of cosmological perturbations, starting from their generation (presumably during a stage in the early universe called inflation). Cosmological perturbations are responsible for cosmic microwave background anisotropies and for the formation of the large scale structure of the universe. Observing these quantities allows cosmologists to derive bounds and constraints on cosmological parameters, and on various possible extensions of the minimal cosmological scenario. These issues are intimately related to the dark matter and dark energy problems, as well as other fascinating questions like the role of neutrinos in cosmology, or like possible observable consequences of high energy physics models (supersymmetry, string theory, large extra dimensions, modifications of gravity...)

Frixione Group Dr. S. Frixione The activity of my group (Stefano Frixione, Valentin Hirschi, Paolo Torrielli) can be broadly defined as collider physics. Our work has a purely phenomenological aspect, and a more formal one. The former activity aims at providing accurate predictions for observables associated with a given process (e.g. $pp\to t\bar{t}$); this typically implies perturbative computations in QCD, in a form that can be easily used for data analysis. The goal of the latter activity, on the other hand, is that of developing techniques with which perturbative computations can be performed. This is mainly done in the context of QCD, but is not limited to it. In the recent past, we concentrated on the problem of interfacing higher-order perturbative results with Parton Shower Monte Carlos, and on the full automation of the calculations of cross sections at next-to-leading order accuracy. In general, our work helps improving the theoretical understanding of hard and semi-hard reactions, and thus puts on firmer ground searches for new physics at colliders