For close on a century, researchers have estimated that the universe contains more matter than can be directly observed known as dark matter. They have likewise watched the presence of dark energy that is more viable than gravitational fascinaton.
Many studies suggested that galaxies that existed 10 billion years ago had almost as much dark matter as the galaxies that exist today. This contradicts prior investigations that suggest that the early universe had less dark matter around worlds.
Now in a new study by the Alfred Tiley from Durham University in England suggests that almost 85% of the total mass of the known universe is made up from dark matter, but this substance doesn’t interact with light, which baffles scientists about its real nature.
So, rather than survey it, cosmologists must depend on dark matter’s gravitational pull on the normal matter, called baryonic matter, that makes up the stars, nebulas, and planets we find in the night sky, and every one of the trees, rocks, and individuals on Earth.
The study used information from two surveys of 1,500 star-forming galaxies and calculated the rotation of galaxies back in time – 10 billion years ago.
Correctly estimating galactic rotation far in the cosmic past is troublesome, on the grounds that these ancient galaxies are amazingly distant and faint. Along these lines, the researchers assessed a normal by bunching the galaxies by separation and afterward joining their light.
Tiley told Live Science said, “Our estimate of the amount of dark matter in galaxies is an average for the whole population at each epoch. The amount of dark matter within individual galaxies might vary significantly.”
He and his team found that the dark matter around the galaxies was equal as the one in the galaxies in our present universe. However, the study contradicts previous studies where they found that galaxies had less dark matter than the younger galaxies.
Reinhard Genzel, an astronomer at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany said, “The study uses only one of the four independent approaches we had used to come to our conclusion.”
Though, the outcomes for the study are highly dependent on the model they used. Ultimately, they chose to use a model that they found to be more representative of the low-mass galaxies scientists believe predominated at the early epoch.
Tiley said, “It appears that the results apply to very massive galaxies at this distant epoch but may not be representative of galaxies with comparatively lower stellar masses, like those that we studied in our work.”
The research was recently submitted to the journal Monthly Notices of the Royal Astronomical Society and published Nov. 16 in the preprint journal arXiv.