Valeria Pettorino - Unveiling the Universe with python
Channel: EuroPython Conference
Date: 2016-08-04

Valeria Pettorino - Unveiling the Universe with python
[EuroPython 2016]
[21 July 2016]
[Bilbao, Euskadi, Spain]
(https://ep2016.europython.eu//conference/talks/unveiling-the-universe-with-python)

I will describe a scientific application of python in the field of
Astrophysics and Cosmology. How the publicly available package Monte
Python is used to compare data from space satellite missions with
theoretical models that attempt to describe the evolution and content
of the Universe. The result is surprising, as it points towards a
Universe which is mainly dark.

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Python is widely used in Cosmology, which is the study of the Universe
and all forms of energy in it. A large amount of data has been
recently obtained through space satellite missions, such as Planck,
financed by ESA/NASA. Planck has observed the radiation emitted about
13 billion years ago (the Cosmic Microwave Background, CMB), which
gives us information on the content and space-time geometry of the
Universe. Many competitive theoretical models have been proposed that
aim at describing the evolution of the species contained in the
Universe: therefore, cosmologists need a method to identify which
theoretical model better fits the data. In order to compare data with
theoretical predictions, cosmologists use Bayesian statistics and
Monte Carlo simulations. Among the tools developed for the analysis,
the package ‘Monte Python’ is publicly available and uses python to
perform Monte Carlo simulations: this allows to determine the
theoretical model that maximizes the likelihood to obtain the observed
data. Such model is now the standard cosmological model and reveals a
Universe that is very different from what scientists had ever
expected. A Universe in which the atoms we are made of, constitute
only 5% of the total energy budget. The rest is the so-called ‘Dark
Universe’.

I will illustrate the story of how cosmologists used python to analyse
the data of the CMB and unveil the Dark Universe.