Credit: Photolibrary
Observations continue to put alternative theories to the test, such as a recent survey of over 10,000 distant galaxies by the Franco-Italian VIMOS-VLT Deep Survey, reported in Nature in January 2008. This compared dark energy with a modified theory of gravity, and found that dark energy provided a slightly better fit to the observational data.
But the results are far from conclusive, and they don't take into consideration that we might be misinterpreting the observations, as suggested by Wiltshire.
What is clear is that our questions on the nature of dark energy are still far from being answered. But a number of new and ongoing experiments may help us gain more insight. Some are Earth-based galactic surveys, such as HETDEX (Hobby-Eberly Telescope Dark Energy Experiment) at the University of Texas in Austin, USA. Some are space-based, such as NASA's proposed JDEM (Joint Dark Energy Mission) to survey more Type 1a supernovae.
Any one of these may yield the evidence necessary to make us as confident of the theory of dark energy as we are of the Big Bang. And if that evidence is not forthcoming, it may take a re-evaluation of the way we're interpreting our observations of distant stars to make sense of our strange cosmos.
Jacqui Hayes is a sub-editor and staff writer with Cosmos in Sydney.
