Stargazers spot dark energy

The distribution of galaxies and the time it takes for galactic clusters to form are behind a University of Queensland claim confirming the existence of dark energy.

Dark energy has been predicted as a defender of Einsteinian models of the universe, ever since the 1990s when astrophysicists identified the accelerating expansion of the universe.

Since the “inflationary universe” didn’t fit with Einstein’s predictions, either Einstein was wrong, or a new form of energy was required.

The great physicist had once recast his equations to include a similar idea, but wasn’t comfortable with the solution and later called it his “greatest blunder”.

The UQ researchers worked with 26 astronomers from 14 institutions in a project conducted at the Anglo-Australian Telescope. The “WiggleZ Dark Energy Survey” mapped the distribution of 200,000 galaxies.

This, according to Professor Michael Drinkwater from the QU School of Mathematics and Physics, is “the first individual galaxy survey to span such a long stretch of cosmic time”.

Generally, supernovae are used as the basis of galactic measurement. This survey instead mapped the distance between galactic clusters, since pairs of galaxies have a statistical preference for being separated by a distance of 490 million light years.

This measurement was used to confirm measurements made using supernova brightness.

The researchers worked with NASA’s Galaxy Evolution Explorer. Along with Professor Drinkwater, the WiggleZ survey was led by Swinburne University’s Dr Christ Blake, Professor Warwick Couch and Professor Karl Glazebrook. ®