Finding the mysterious 'monster' that is making the universe expand

British scientists have discovered what could be the source of the dark energy that is keeping the universe expanding. It's a monster that lives in the galaxy that contains Earth.

By comparing monster black holes over the past 9 billion years of the universe's history, astronomers have found clues that they may be the source of a mysterious force that makes up 68 percent of the universe called dark energy, according to Live Science. It is dark energy that drives our universe to continue expanding rapidly even more than 13.8 billion years after the Big Bang.

The monster black hole mentioned is a type of supermassive black hole lurking in the hearts of large galaxies , of which Sagittarius A* at the center of the Milky Way galaxy is an example.

An illustration of a monster black hole - (Photo: SHANGHAI ASTRONOMICAL OBSERVATORY).

"If the theory is correct, this would revolutionize all of cosmology, because we would finally have a solution for the origin of dark energy that has puzzled cosmologists and theoretical physicists for over 20 years," said co-author Chris Pearson from the Rutherford Appleton Laboratory (RAL - UK).

The work aims to find a solution to a phenomenon that has been demonstrated over the past century that the universe is now expanding at a faster rate than ever, contrary to the prediction of a "big crunch" that would have the opposite effect of the Big Bang, causing the universe to gradually degenerate.

The hypothetical 'big crunch'   was driven by gravity—which is ubiquitous in the universe—making the universe collapse in on itself over time. So something strong enough to counteract gravity would have to push the elements of the universe farther apart.

That mysterious force is called dark energy , but for many years scientists have been unable to explain exactly what it is.

For dark energy to be powerful enough to counteract the degeneracy of the universe, it would need to be extremely ubiquitous.

Two independent research teams teamed up to find the clue by comparing the masses of central black holes in two different groups of galaxies, one young and distant, 9 billion light-years away, and one closer and older.

The results show that in the universe, recent galactic center monster black holes have ballooned to 7-20 times larger than the monster black holes of the early universe , a monstrous development that cannot be explained by black hole mergers.

From this, the researchers showed that black holes must grow in step with the universe. They crush stars at their cores with dark energy and expand, pushing the entire universe to expand with it.

According to co-author Dave Clement from Imperial College London, they may have found the answer to one of the biggest problems in cosmology.

The results were published in two papers in The Astrophysical Journal and The Astrophysical Journal Letters.

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