University of Portsmouth, UK | 2020 Jun 03
A new paper has shown how large structures in the distribution of galaxies in the Universe provide the most precise tests of dark energy and cosmic expansion yet.
- A section of the three-dimensional map of galaxies Sloan Digital Sky Survey used in this analysis. The rectangle on the far left shows a patch of the sky containing nearly 120,000 galaxies (a small fraction of the total survey). The centre and right images show the 3D map created from these data: brighter regions correspond to the regions of the Universe with more galaxies, and darker regions to voids. Image credit: Jeremy Tinker and the SDSS-III collaboration
The study uses a new method based on a combination of cosmic voids – large expanding bubbles of space containing very few galaxies – and the faint imprint of sound waves in the very early Universe, known as baryon acoustic oscillations (BAO), that can be seen in the distribution of galaxies. This provides a precise ruler to measure the direct effects of dark energy driving the accelerated expansion of the Universe.
This new method gives much more precise results than the technique based on the observation of exploding massive stars, or supernovae, which has long been the standard method for measuring the direct effects of dark energy. ...
This new method gives much more precise results than the technique based on the observation of exploding massive stars, or supernovae, which has long been the standard method for measuring the direct effects of dark energy. ...
Testing Low-Redshift Cosmic Acceleration with Large-Scale Structure ~ Seshadri Nadathur et al
- Physical Review Letters 124(22):1301 (05 Jun 2020) DOI: 10.1103/PhysRevLett.124.221301
- arXiv.org > astro-ph > arXiv:2001.11044 > 29 Jan 2020 (v1), 21 May 2020 (v2)