For the first time, a group of cosmologists say they’ve created virtual galaxies inside their computers without any dark matter. Critics of dark matter see it as a win for a controversial model of how our universe formed called MOND, or Modified Newtonian Dynamics. But this one result isn’t likely to convince most astronomers they should abandon decades of dark matter theory.

Research describing the new simulation is set for publication in the Astrophysical Journal.

The birth of galaxies

Our universe was born from the Big Bang some 13.8 billion years ago. And from the beginning, matter wasn’t evenly distributed. Some parts of the cosmos were denser than others.

Astronomers know these variations existed because they can see them in the Cosmic Microwave Background (CMB) radiation — the relic radiation leftover from the Big Bang. Gravity pulled more and more dark matter — the invisible material that binds the universe together — and normal matter into these regions until it formed a vast web of cosmic filaments that’s now spun throughout our universe. The first stars, and eventually galaxies, formed here.