Scientists reconstruct gravity to better understand the universe

A Simon Fraser University physicist led an international team of scientists in reconstructing the laws of gravity-to gain a better understanding of how they work in the larger universe. The study, published in Nature Astronomy and featured in The Conversation , explored whether modifying General Relativity could help resolve some of the open problems of cosmology. SFU Professor Levon Pogosian says that, while laws of gravity as laid out by Newton and Einstein work well in our solar system, there are still questions around how they work beyond it. -The gaps in our understanding appear when we when we try to apply these laws to the entire universe,- says Pogosian, who also organizes biennial international conferences on Testing Gravity at the SFU Harbour Centre in Vancouver. -To describe the universe using Einstein's theory we need to introduce dark matter and dark energy - two ingredients that together make up 95 percent of the universe and whose nature we do not understand. Moreover, different ways of measuring the rate of cosmic expansion appear to give different answers - a serious problem in cosmology known as the Hubble Tension. The standard model of cosmology is based on General Relativity, which describes gravity as the curving or warping of space and time that bends the pathways along which light and matter travel.