We know it began with a "big bang" 13 billion years ago. But what has happened since during the formation of the universe? And what might it have looked like?
Many simulations have been produced over the years following the evolution of the universe.
But most were deficient in some way, reproducing the ‘cosmic web’ of galaxies that we see in the universe, but failing to create mixed populations of galaxies or predict gas and metal content.
However, a new study by scientists in the US has gone a step further than previous attempts, simulating the evolution of the universe in such a way that reproduces features - such as galaxy distribution and composition - more accurately than ever before.
Published in the journal Nature, the new model correctly predicts characteristics described in observational studies, and represents a considerable step forward in modelling galaxy formation.
The research is the work of the Illustris project - a large cosmological simulation of galaxy formation.
The simulation starts 12 million years after the Big Bang and traces 13 billion years of cosmic evolution.
The resulting model is a mix of spiral and elliptical galaxies and measurements of hydrogen and metal content consistent with data previously measured by scientists.
The model covers the evolution of different elements of galaxies, including both visible and dark matter.
The effort was possible because of significant forward steps in the power of computers, better algorithms and developments in physics models.
Running the simulation took approximately 16 million central processing unit hours.
This latest simulation does not, however, mark the end of the process of trying to model how the universe developed.
As powerful as it is, Illustris is still not strong enough to model the formation of powerful black holes, for example, or the fine detail of galaxies surrounding the Milky Way.
