Scientists are attempting to re-create the universe for the first time using the "full" version of Albert Einstein's general theory of relativity.
The complex equations will be used to generate the most accurate computer simulation of the cosmos yet.
Einstein's theory explains how gravity arises from the way massive objects, such as the Earth, curve space and time.
Because the mathematics are so mind-boggling, physicists until now have been forced to simplify the theory when applying it to the universe.
Now, research teams in the US and Europe have independently created two universe-modelling computer codes using the complete theory.
Dr Marco Bruni, one of the scientists from the Institute of Cosmology and Gravitation (ICG) in Portsmouth, said: "This is a really exciting development that will help cosmologists create the most accurate possible model of the universe.
"Over the next decade we expect a deluge of new data coming from next generation galaxy surveys, which use extremely powerful telescopes and satellites to obtain high-precision measurements of cosmological parameters - an area where ICG researchers play a leading role.
"To match this precision we need theoretical predictions that are not only equally precise, but also accurate at the same level.
"These new computer codes apply general relativity in full and aim precisely at this high level of accuracy, and in future they should become the benchmark for any work that makes simplifying assumptions."
The programs are the first to use the complete general theory of relativity to account for the effects of matter clumping in some regions and being absent from others.
Both groups have applied the Einstein field equations, which describe complicated relationships between the matter content of the universe and the curvature of space and time, at billions of places and times over the history of the universe.
