Highlights and Conclusions of the Chalonge 13th Paris Cosmology Colloquium

TL;DR

The Colloquium summarized recent cosmological data and theories, emphasizing the Gaussian nature of primordial fluctuations, the consistency of dark energy with a cosmological constant, and the favoring of light dark matter over heavy WIMPs.

Contribution

This report consolidates expert insights and observational data, highlighting the current status and future prospects in cosmology and dark matter research.

Findings

Primordial CMB fluctuations are nearly Gaussian.

Dark energy aligns with the cosmological constant.

Light dark matter candidates are increasingly favored.

Abstract

The 13th Chalonge Paris Cosmology Colloquium was held at the historic Perrault building of Observatoire de Paris on 23-25 July 2009. The Colloquium was held in the spirit of the Chalonge School, putting together real cosmological and astrophysical data and hard theory predictive approach in the framework of the Standard Model of the Universe. Peter Biermann, James Bullock, Claudio Destri, Hector de Vega, Massimo Giovannini, Sasha Kashlinsky, Eiichiro Komatsu, Anthony Lasenby and Norma G. Sanchez present here their highlights of the Colloquium. The summary and conclusions by H. J. de Vega, M. C. Falvella and N. G. Sanchez stress among other points: (i) the primordial CMB fluctuations are almost gaussian, large primordial non-gaussianity and large running index are strongly disfavored. The primordial graviton ratio r is predicted in the effective theory of inflation to be between 0.021 and 0.053, at reach of the next CMB observations. (ii) Dark energy observations are consistent with the cosmological constant. (iii) The cosmic ray positron excess recently observed is explained by natural astrophysical processes. (iv) The heavy dark matter particle candidates ( > 1 GeV, wimps) became strongly disfavored, while cored (non cusped) dark matter halos and light (keV scale mass) dark matter are being increasingly favored from theory and astrophysical observations. The Daniel Chalonge Medal 2009 was awarded to Peter Biermann during the Colloquium. Photos of the Colloquium are included.