What did the Universe look like 7 billion years ago? VIPERS (the VIMOS Public Extragalactic Redshift Survey) is mapping the distribution of galaxies at redshift 1, an epoch when the Universe was half its present age. VIPERS is an ESO large project with an international team led by DarkLight investigator Luigi Guzzo. VIPERS observes a critical period in cosmic history when dark…
Tag: dark energy
A confirmation of the cooling power of voids
The standard cosmological model predicts that photons will heat up slightly while crossing the strong gravitational potential of a massive cluster of galaxies. Conversely, while crossing a void – a region of space empty of galaxies – photons will cool down. On large scales of hundreds of megaparsecs the effect is due to the accelerating expansion rate of space and…