New Delhi | Jagran News Desk: A group of scientists from Durham University, UK have simulated the evolution of cosmos based on the "Chameleon Theory", an alternative of general relativity theory of Albert Einstein, with the help of a supercomputer. The new finding suggests that the theory of relativity may not be the only way to explain how gravity works in the evolution of the Universe.

The findings show the viability of Chameleon Theory, so called because it changes behaviour according to the environment, as an alternative to General Relativity in explaining the formation of structures in the universe.

The findings are published in Nature Astronomy.

"'Chameleon Theory' allows for the laws of gravity to be modified so we can test the effect of changes in gravity on galaxy formation," said Christian Arnold, a physicist at the Institute for Computational Cosmology at Durham University and co-author of the new study.

"Through our simulations, we have shown for the first time that even if you change gravity, it would not prevent disc galaxies with spiral arms from forming. This does not mean the general relativity is wrong, but it does show that it does not have to be the only way to explain gravity's role in the evolution of the Universe," he added.

This research may also help identify dark matter, a hypothetical invisible mass that is believed to have a gravitational effect on galaxies and other bodies. This constant force in the theory of general relativity can account for the expansion of the universe, but does so by including a vast amount of dark matter that cannot be observed and remains unconfirmed.

The study also looked at the effect of modified gravity on supermassive black holes, which eject heat and material that burns away at the gas needed to form stars. The energy emitted from black holes also feeds nuclei found in galaxies, and therefore plays a major role in galaxy formation. 

However, the findings suggest that, even with different gravity laws decreasing the amount of heat being ejected by black holes, galaxies still formed in the simulated model of the universe just like they do in the actual universe. 

General Relativity was developed by Albert Einstein in the early 1900s to explain the gravitational effect of large objects in space, for example to explain the orbit of Mercury in the solar system.
It is the foundation of modern cosmology but also plays a role in everyday life, for example in calculating GPS positions in smartphones.

The research team is now planning to test their findings through the Square Kilometer Array (SKA), a group of radio telescopes located in Australia and South Africa, scheduled to run by mid-2020.

Posted By: Talib Khan