Scientists Unleash Full Einstein Equations To Model The Universe

Today, 100 years after General Relativity was developed, our computers are finally ready to use its full power to better model the universe.
US and European researchers have independently created two new computer codes that can use the complete theory and not just its averaged version. This will allow us to discover what the impact of the clumps of matter and voids are in the overall large structure 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,” said Dr Marco Bruni, a cosmologist from the University of Portsmouth and co-author of one of the studies, in a statement.
“To match this precision we need theoretical predictions that are not only equally precise, but also accurate at the same level.”
The paper from Bruni and Eloisa Bentivegna from the University of Catania is published in the Physical Review Letters, while the American study from Case Western Reserve University and Kenyon College, Ohio will be in Physical Review D.
Einstein’s theory of relativity remains the best theory of gravity we have, consistently passing high-precision tests in the Solar System as well as successfully predicting phenomena such as gravitational waves, which were discovered earlier this year.
Both computer codes use the 10 Einstein Field Equations, which describe how the effect of gravity as a result of matter curving space-time. These equations are notoriously difficult to solve, and the solutions that are used in physics are usually founded on simplification or assumptions, such as symmetry.
“No one has modeled the full complexity of the problem before,” said Professor Glenn Starkman of the American team.
“These papers are an important step forward, using the full machinery of general relativity to model the universe, without unwarranted assumptions of symmetry or smoothness. The universe doesn’t make these assumptions, neither should we.”
In the early days of general relativity, a curious solution was discovered where a star could be so big and dense that its light never escaped it. Although at first it was considered an unrealistic quirk, the solution is what we today call a black hole. Harnessing the full extent of general relativity will lead to a clearer and deeper understanding of the universe.