There may be a 'dark mirror' universe within ours where atoms failed to form, new study suggests

[JoseBalow]

4. I don't understand how this image was produced

If dark matter is invisible, how can it be depicted in the blue areas of the image? Was it's gravitational influence somehow measured and added to the composite? Or is it just a theoretical representation?

It doesn't interact with light or normal matter. The only way scientists can detect it is through its subtle gravitational influence on normal matter, such as the motions of stars within galaxies and the growth of super-large structures in cosmic time.