New research, based on observations of early supermassive black holes and galaxies, offers an answer to a classic question in astronomy: were there black holes or galaxies first?
Astronomers have long been dealing with their own version of the famous chicken-and-egg dilemma. They are interested in what appeared earlier in the early universe and had a greater influence on its formation – supermassive black holes or galaxies? Standard ideas assume that supermassive black holes only formed after the first stars and galaxies appeared in the universe.
A research team led by Joseph Silk from the Sorbonne in France, scientists from the American Johns Hopkins University (JHU) and the British Oxford analyzed the observations made by the James Webb Space Telescope to date in connection with this complicated question. The scientists‘ conclusions change previous ideas and show that supermassive black holes appeared very soon after the creation of the universe, and then their activity enhanced the formation of stars and the formation of galaxies.
Research results recently published in the Astrophysical Journal Letters suggest that supermassive black holes appear to have dramatically accelerated the birth of new stars during the first 50 million years of the universe’s history. At the same time, they coexisted with emerging galaxies and interacted with each other.
„We’ve known for some time that these gravitational monsters exist inside galaxies that are relatively nearby in space,“ explains Silk. „But now we are surprised by the fact that we also observe supermassive black holes practically at the beginning of the universe, where they essentially represent the basic building blocks of early galaxies.“
According to Silk’s team, the young universe had two phases. In the first, jets from black holes accelerated star formation. A few hundred million years after the Big Bang, scientists say, the gas cloud collapsed due to the magnetic storms of the supermassive black holes, and new stars were born at this stage of development at a rate that far exceeded the rate observed billions of years later in classical galaxies. In the second phase of the development of the young universe, the jets of black holes slowed down, went into a state of conservation of energy, and thus the volume of gas for the formation of new stars decreased in the galaxies.
„Supermassive black holes literally drove fundamental processes in the early universe,“ Silk continues. “They represented gigantic amplifiers of star formation, which is the opposite of what we thought about supermassive black holes in the early universe until recently. Our findings show that the jets of early black holes pierced the cosmic gas clouds of the time and thus triggered the processes of star formation in them.‘
