The most mysterious phenomenon in cosmology – dark energy – may not exist at all, according to Professor Subir Sarkar, head of the particle theory group at the University of Oxford in the UK.
In the late 1990s, astronomers found evidence from supernovae that the universe has been expanding faster and faster as it gets older. Having no explanation for what was driving it, they dubbed this accelerating expansion ‘dark energy’. What did you think about these findings at the time?
‘I was sceptical from the beginning. I’m unusual in the cosmology community in that I’ve had experience working in experiments as well as theory, and I didn’t think the astronomers were taking full account of the systematic uncertainties in their data. But for a long time, the data were not made available for checking. That changed in 2014 when an international collaboration published a catalogue of all the relevant supernovae – publicly, for the first time.’ […]
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