Cosmology is the branch of astronomy that studies the large-scale properties of the universe, including its evolution from the Big Bang until today and into the future. An important hypothesis of current cosmology is the existence of dark energy, an unknown form of energy permeating all space and accelerating the observable expansion of the universe. According to the standard model of cosmology, dark matter, a hypothetical type of matter distinct from ordinary matter, together with dark energy constitute more than 95% of the total mass–energy content of the universe. Our scientific partner in this case study, Dr. Martin Sahlén, works at the intersection of theoretical and observational cosmology, with an emphasis on modelling and constraining dark energy. His work at the Universities of Oxford and Uppsala aims at testing fundamental assumptions of the standard model of cosmology.
In this case study cosmological data from observations (surveys) and simulations has been used. Martin Sahlén is an active member of the XMM Cluster Survey collaboration that produced a galaxy cluster survey using archival X-ray data taken by ESA’s XMM-Newton satellite. The survey aims at the derivation of cosmological parameters and released a catalogue with data of 503 optically confirmed galaxy clusters in 2012. TP commissioned three artists to perform transpositions of this data set. Artemis-Maria Gioti created an installation for player piano for the DA TA rush research event in Vienna, and Marcus Wrangö and Magnus Bunnskog produced audio-visual installations for the final research event in Stockholm.
The second data set used in this case study was extracted from the online database of the Virgo consortium and stems from the Millenium II dark matter simulation. This N-body simulation is used to investigate how the distribution of matter in the Universe has evolved over time and contains 64 time steps. For each time step the positions of galaxy clusters of a certain minimum number of simulation particles have been selected. As such clusters formed in the universe only after a certain time, the data used starts at time step 11, resulting in 53 steps used in our transpositions. <tbc>