Séminaire / Seminar GReCO |
| « Constraining the Nature of Dark Energy from Cosmological Observations » |
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U. Alam |
| Dark energy is one of the most tantalizing mysteries in current cosmological research. A host of observations confirm that about two-thirds of the energy content of the universe comprises of this negative-pressure ""dark energy"" component that causes the expansion of the universe to accelerate. In my talk, I will explore two distinct facets of dark energy research. Many different theoretical models have been suggested for dark energy. One aspect of my research is to study these theoretical models, such as early dark energy models, and constrain them in light of current observations. A second approach to the dark energy problem is to study the various observations available to us with different statistical tools, and optimize these methods for obtaining maximum information on the dark energy parameters. In this talk I will outline a new, nonparametric method for reconstructing w(z) based on Gaussian Process modeling. Applying this method on diverse datasets such as Type Ia supernovae and baryon acoustic oscillations, it is possible to obtain strong constraints on non-trivial behaviour of the equation of state of dark energy. Using these two complementary approaches we expect to shed light on the nature of dark energy. |
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lundi 5 septembre 2011 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |