Researchers who are looking for new ways to probe the nature of gravity and dark energy in the universe have adopted a new strategy: looking at what’s not there.
In a paper to appear in upcoming issue of Physical Review Letters, the international team of astronomers reports that they were able to achieve four times better precision in measurements of how the universe’s visible matter is clustered together by studying the empty spaces in between.
Paul Sutter, study co-author and staff researcher at The Ohio State University, said that the new measurements can help bring astronomers closer to testing Einstein’s general theory of relativity, which describes how gravity works.
Sutter likened the new technique to learning more about Swiss cheese by studying the holes. The voids, he pointed out, are only empty in the sense that they contain no normal matter. They are, in fact, full of invisible dark energy, which is causing the expansion of the universe to accelerate.