A team of researchers based in Durham University, Germany, China, and Harvard University have led a breakthrough in dark matter research that could allow it to be identified in space.
The researchers simulated a simplified model of our universe using supercomputers, allowing them to zoom in on very small clumps of ‘dark matter’. A zoom of this magnitude is unthinkably powerful – equivalent of zooming into a fly on the Moon’s surface. Through this simulation, the researchers aim to construct a series of complex dark matter maps.
These detailed maps of virtual dark matter clumps, known as ‘haloes’, provide a starting point to eventually allow for the discovery of dark matter in actual space.
Dark matter is thought to make up around 27% of the universe and is postulated to take several forms, loosely grouped into ‘hot’ or ‘cold’ dark matter. High-energy randomly moving particles created soon after the Big Bang make up hot dark matter and weakly interacting particles make up cold. Like normal matter, dark matter also possesses ‘anti-’ particles. When dark matter particles collide with dark matter anti-particles near halo centres, both are converted into a burst of gamma-ray radiation. These bursts of radiation are the signals that scientists are able to zero-in on when searching for elusive dark matter.
Professor Carlos Frenk, Ogden Professor of Fundamental Physics at Durham’s Institute for Computational Cosmology, said: “By zooming in on these relatively tiny dark matter haloes we can calculate the amount of radiation expected to come from different sized haloes. This would confirm the hypothesised nature of the dark matter, which may not be entirely dark after all.”
Cooling gases at the centre of these dark matter haloes are responsible for the birth of galaxies. Haloes can vary in size massively, from smaller ones containing too small to contain a galaxy to the biggest that can contain hundreds of galaxy clusters.
Published in the journal Nature, this research could allow the radiation from dark matter haloes too small to contain stars to be observed by gamma-ray observatories in the future. The smallest haloes have remained relatively elusive to scientists thus far, however the supercomputer simulations performed by this research group may pave the road for future studies focusing on the identity and role of dark matter in our universe.
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