United Kingdom, July 15 (Canadian-Media): Supercomputer simulations of galaxies have shown that Einstein's theory of General Relativity might not be the only way to explain how gravity works or how galaxies form, Science X Newsletter reports said.
Computer generated images showing a disk galaxy from a modified gravity simulation.Images show (right side of image, in red-blue color) the gas density within the disk of the galaxy with the stars shown as bright dots. The left side of the images show the force changes in the gas within the disk, where the dark central regions correspond to standard, General Relativity-like forces and the bright yellow regions correspond to enhanced (modified forces). Images show views of the simulated galaxy from above and the side. Credit: Christian Arnold/Baojiu Li/Durham University.
Physicists at Durham University, UK, simulated the cosmos using an alternative model for gravity—f(R)-gravity, a so called Chameleon Theory.
The resulting images produced by the simulation show that galaxies like our Milky Way could still form in the universe even with different laws of gravity.
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 research could also help further understanding of dark energy—the mysterious substance that is accelerating the expansion rate of the universe.
The findings are published in Nature Astronomy.
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.
Scientists already know from theoretical calculations that Chameleon Theory can reproduce the success of General Relativity in the solar system.
The Durham team has now shown that this theory allows realistic galaxies like our Milky Way to form and can be distinguished from General Relativity on very large cosmological scales.
Research co-lead author Dr. Christian Arnold, in Durham University's Institute for Computational Cosmology, said: "Chameleon Theory allows for the laws of gravity to be modified so we can test the effect of changes in gravity on galaxy formation.