What we see in the night sky is only five per cent of the Universe. So what’s the other 95 per cent of the Universe made of – a young physicist has the answers across Tasmania this week.
One of Australia’s leading young physicists will reveal the dark secrets of the Universe in Tasmania this week with a series of school and public talks in Burnie, Launceston, Devonport and Hobart.
Dr Tamara Davis is a L’Oréal Australia Fellow, the 2011 national Women in Physics lecturer, an astrophysicist at the Universities of Queensland and Copenhagen, and good talent.
Earlier this year she and her colleagues confirmed that dark energy is real – by observing thousands of ancient exploding stars. The work confirms again Einstein’s Theory of General Relativity and the ‘standard model’ of our Universe.
In 1998 Australian astronomers were competing head to head with a US team to measure if the Universe is expanding or contracting – by using supernovae as ‘standard candles’.
Their results turned astronomy on its head. Both teams found that the Universe was not just expanding, but that the expansion was accelerating.
“The discovery of acceleration was an enormous shock, because it broke our models of how the Universe works,” Tamara says.
Back to dark energy
The models were fixed by invoking dark energy.
Using the concept of dark energy astrophysicists could repair the model. But is dark energy real?
That’s where the WiggleZ Dark Energy Survey came in: Tamara was one of 26 astronomers from 14 different institutions who took four years to look at over 200,000 galaxies.
The team led by Dr Chris Blake from Swinburne University and Professor Michael Drinkwater from The University of Queensland, used the Anglo-Australian Telescope near Coonabarabran, NSW to provide an independent check on the supernova results. They measured the pattern of how galaxies are distributed in space and how quickly clusters of galaxies formed over time, to confirm the observations from supernovae.
Earlier this year their results confirmed that dark energy is real.
So now we know that everything we can see in the night sky – planets, stars, gas clouds, galaxies etc – make up only four per cent of the Universe. 24 per cent is dark matter. But most of our Universe (over 70%) is dark energy.
Tamara is giving a free public talk in Hobart this Wednesday 28 September at 8pm, in Physics Lecture Theatre1, Sandy Bay Campus, University of Tasmania.
She’s also talking at schools in Burnie, Launceston, Devonport and Hobart.
The Australian Institute of Physics Women in Physics Lecture Tour celebrates the contribution of women to advances in physics.
Photo courtesy L’Oréal Australia.
For interviews with Tamara Davis, call Andrew Wight on (03) 9398 1416
- Tour details, locations and school contacts at http://bit.ly/oF24FK
- Further information call Andrew Wight on (03) 9398 1416
- More about Tamara including photos and video http://www.scienceinpublic.com/loreal/fellows/on-the-hunt-for-dark-energy and at Tamara’s Home http://bit.ly/nobnnA
- More information on WiggleZ Dark Energy Survey: http://wigglez.swin.edu.au/site/