Chameleon Theory: Is Einstein’s General Relativity Theory Only Way To Explain Gravity?

Eddie Gonzales Jr. – – Physicists at Durham University, UK, simulated the cosmos using an alternative model for gravity — f(R)-gravity, a so called Chameleon Theory.

Simulations of galaxies have shown that galaxies like our Milky Way could still form in the universe even with different laws of gravity, and Einstein’s theory of General Relativity might not be the only way to explain how gravity works or how galaxies form.

Computer simulation of a disc galaxy. Credit: Christian Arnold/Baojiu Li

Computer simulation of a disc galaxy. Credit: Christian Arnold/Baojiu Li

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.

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.

“Chameleon Theory allows for the laws of gravity to be modified so we can test the effect of changes in gravity on galaxy formation,” research co-lead author Dr Christian Arnold, in Durham University’s Institute for Computational Cosmology, said in a press release.

“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.

“Our research definitely does not mean that 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.”


Written by Eddie Gonzales Jr. – Staff