Interview with Stavros Katsanevas Chairman of the General Assembly of APPEC
INFN Newsletter November 2014
Stavros Katsanevas
Astroparticle physics was born at the intersection of astrophysics, particle physics and cosmology. It had multiple origins: the movement towards underground laboratories to study the decay of the proton and neutrino properties, the first detection of high energy photons using particle physics methods, the large surveys searching for astronomical dark matter. Today it addresses the physics of primordial Universe, the nature of dark matter and dark energy; the eventual unification of fundamental interactions; the properties of neutrinos and their role in cosmic evolution; the origin of cosmic rays; the Universe at extreme energies studied using multi-messenger probes including high energy cosmic rays, photons, neutrinos and gravitational waves.
After the Higgs discovery, with the measurement of neutrinos oscillations and the precision results the PLANCK satellite, we have for the first time the theoretical and experimental possibility to formulate a coherent picture of the Universe covering a multitude of energy scales: from the electroweak symmetry breaking scale, or Higgs scale if you wish, to this of inflation.
Our understanding of the early Universe has greatly increased in the past few years due to the high-quality observational data on the cosmic microwave background and large scale structure. The unprecedented precision of the Planck results enabled to significantly restrict the range of allowed inflationary models. The quest for measuring the primordial B-mode polarization, which would have profound implications, has acquired a new boost from the results of BICEP2 collaboration. Still, the remaining possibilities are too diverse and a theoretical input is required to reduce them further. It is time to ask what common features distinguish the inflationary models favored by the data, what symmetry principles can stand behind them and how they can be incorporated in a complete quantum theory containing the Standard Model and gravity.
The reheating stage that follows inflation in the evolution of the Universe is characterized by violent dynamics, whose details are highly model-dependent. Therefore any direct observational signal from this stage can potentially teach us a lot about the theory describing Nature at energy scales well beyond those reached at colliders. However, in general, most probes carrying information from reheating are either inaccessible by current technology, degenerate with other post-reheating phenomena, or washed away by the subsequent thermalization. It is important to understand, which part of the information remains and how it can be decoded.
The aim of this Theory Institute is to bring together researchers interested in the physics of the early Universe to discuss the above and related questions. The program will include review talks on the latest experimental data including the Planck release expected at the end of 2014. The Institute is funded jointly by CERN and by Korean Government under the CERN-Korea Collaboration agreement; it is included in the framework of the PACT activities in 2015 with the support from APPEC.
Topics:
Inflationary theory in light of latest experimental data
Universality classes of inflationary models
Embedding inflation into quantum gravity
Consistent theories of graceful exit and reheating
Primordial non-Gaussianities and gravitational waves
Large Scale Structure as a probe of the early Universe
Other future probes
Organizers: Diego Blas, Daniel Figueroa, Deog-Ki Hong, Julien Lesgourgues, Antonio Masiero, Antonio Riotto, Sergey Sibiryakov
