There’s a lot we can learn by looking at all those voids making #space between galaxies – and now, for the first time, #astronomers have used a new method to peer inside these mysterious pockets of #nothingness.
Voids in space are due to the expansion of the Universe – this results in a web of material with spaces in between the filaments. Think of pulling apart a grilled cheese sandwich, if the cheese were made of strings of galaxies.
Cosmic voids can be detected in something called the #cosmic microwave background (CMB), a remnant of electromagnetic radiation left behind by the #Epoch of Recombination around 380,000 years after the #Big Bang.
The CMB represents the first light appearing in the Universe, and in it, cosmic voids seem to correlate with temperature. Hotter regions are associated with the filaments, and the colder regions associated with the voids.
Now, for the first time, researchers have used this CMB map to study the cosmic voids. Led by David Alonso of Oxford University in the UK, a team of researchers has mapped 774 cosmic voids to the CMB to study the properties of the gas that floats therein.
They used data from something called the Baryon Oscillation Spectroscopic Survey (BOSS), which surveyed sound waves that rippled through the early universe like ripples through a pond, and can still be detected throughout the Universe as regular fluctuations in the normal matter.
Full article here.
David Alonso, J. Colin Hill, Renée Hložek, and David N. Spergel
Phys. Rev. D 97, 063514 – Published 14 March 2018