Dark matter analysis challenges conventional thinking
21 Dec 2016 by hddbqtthcb.d hddbqtthcb.d
An international team of scientists have discovered that dark matter is less dense throughout space, than previously thought.
An international team of scientists have discovered that dark matter is less dense throughout space, than previously thought.
The astronomers also found dark matter was more smoothly distributed than expected compared to data that had been analysed from the Planck-CMB experiment. These new findings were discovered by the team using weak gravitational lensing – the bending of light by gravity – to map how dark matter was distributed.
Professor Catherine Heymans of the University of Edinburgh's School of Physics and Astronomy, who co-led the study, said to Laboratory News: "One explanation of this discrepancy is that dark energy has actually been evolving over time, slowing down the build-up of massive clumpy structures of dark matter in the Universe.”
Scientists carried out the study at the European Southern Observatory in Chile. To eliminate bias, three sets of data - that included two false sets - were used, with scientists only finding out at the end of the experiments which sets were false.
The astronomers’ study represents the largest area of the Universe to be mapped using weak gravitational lensing. Previous ideas on dark matter distribution had been based on an image taken time shortly after the Big Bang by the European Space Agency’s Planck satellite, with a theoretical model projecting how the Universe should appear today.
Dr Hendrik Hildebrandt of the Argelander Institute for Astronomy in Germany, who co-led the study, said: "Our findings will help to refine our theoretical model for how the Universe has grown since its inception, improving our understanding of the modern day Universe."
The team of astronomers was comprised of scientists from the University of Edinburgh, the Argelander Institute for Astronomy in Germany, Leiden University in the Netherlands and Swinburne University of Technology, based in Australia. All these institutions are part of an ongoing project called Kilo Degree Survey, supported by the European Research Council.
This research, published in Monthly Notices of the Royal Astronomical Society, was carried out to better understand the evolution of the Universe over the last 14 billion years.
