How to create a black hole from nothing

Black holes were thought to be formed by the collapse of dead stars. But Webb telescope images of the early universe suggest a different path.

How many ways are there to leave our universe? Perhaps the most famous of these is the one associated with the death of a star. In 1939, University of California, Berkeley physicist J. Robert Oppenheimer and his student Hartland Snyder discovered that when a sufficiently large star runs out of thermonuclear fuel, the star collapses inward, collapsing, and remains forever inside. predicted that it would continue to fall and thereby condense. space, time and light. It wraps around itself into what is now called a black hole. However, it turns out that dead stars are not necessary for black holes to form.

Instead, at least in the early Universe, giant clouds of primordial gas could collapse directly into black holes, avoiding the millions of years stars spend in space. This tentative conclusion was recently reached by a team of astronomers studying his UHZ-1, a light spot that appeared shortly after the Big Bang. In fact, UHZ-1 is a powerful quasar that spewed fire and X-rays from a massive black hole 13.2 billion years ago, when the universe was very young, 500 million years after its creation.

From a cosmic perspective, this is an unusually short amount of time for such a massive black hole to form as a result of star collapse and merger. Priyamvada Natarajan, a Yale University astronomer and lead author of a paper published in the Astrophysical Journal Letters, and her colleagues discovered a new type of galaxy called a supermassive black hole galaxy (SBL) in UHZ-1. announced that they had discovered a celestial object. . Essentially, GSNHs are young galaxies associated with black holes that have grown too large too quickly. The discovery of this quasar could help solve a related mystery that has puzzled astronomers for decades.

Almost every visible galaxy in the modern universe appears to have a supermassive black hole at its center, millions or even billions of times more massive than the Sun. Where do these monsters come from? Can a normal black hole grow this quickly? Dr. Natarajan and his colleagues believe that UHZ-1, perhaps like many supermassive black holes, began as a primordial cloud. These clouds could collapse into extremely heavy nuclei, which was enough to fuel the growth of supermassive galaxies with black holes. This is yet another reminder that the universe we see is controlled by an invisible, dark geometry.

“As a first candidate for HBSH, UHZ-1 provides convincing evidence for the formation of heavy primordial nuclei by direct decay in the early Universe,” the authors write. Natarajan and his friends. “Nature seems to create black hole seeds in more ways than just star death!” Daniel Holtz, a theorist at the University of Chicago who studies black holes, said in an email. added. If this is true, this is a very interesting black hole. ”

He added: “It’s too big and it’s too early. It’s like walking into a kindergarten class and suddenly finding a 5-year-old weighing 80 kg and standing on one leg.” Astronomers talk about the evolution of the universe According to the story, the first stars were condensed from hydrogen and helium. Clouds left behind by the Big Bang. They burned fast and hot, quickly exploding and collapsing into black holes 10 to 100 times the mass of the Sun.

Over centuries, subsequent generations of stars emerged from the ashes of earlier stars, enriching the chemical composition of the universe. And the black holes left after their deaths continued to merge and somehow grow, turning into supermassive black holes at the centers of galaxies. The James Webb Space Telescope, launched on Christmas Day two years ago, was intended to test this idea. It has the largest mirror in space, measuring 6.5 meters in diameter. More importantly, it is designed to detect infrared wavelengths of light from the most distant, or earliest, stars in the universe.

But as soon as new telescopes were pointed at the sky, new galaxies came into view that were bigger and brighter than cosmologists expected. In recent years, there has been debate about whether these observations pose a threat to long-standing models of the universe. According to this model, the universe is made up of tiny amounts of visible matter, incredible amounts of “dark matter” that provides the gravitational force that holds galaxies together, and “dark energy” that pulls them apart. The discovery of UHZ-1 represents an important milestone in this debate.

In preparation for future observations of the massive galaxy cluster in the constellation Sculpter with the James Webb Space Telescope, Dr. Natarajan and his team requested time to work at NASA’s Chandra X-ray Observatory. The cluster’s mass acts like a gravitational lens, magnifying objects far back in spacetime. The researchers wanted to see everything that this lens would bring to the surface with his X-ray light. They discovered quasars powered by supermassive black holes 40 million times more massive than the Sun.

Further observations with the Webb telescope confirmed that it is 13.2 billion light years away. (The Sculptor Cluster is about 3.5 billion light years away.) It was the oldest and earliest discovered quasar in the universe. “It took Webb to discover this incredibly distant galaxy, and we needed Chandra to discover its supermassive black hole,” Akos Bogdan of the Harvard-Smithsonian Center for Astrophysics said in a press release. Stated. “We also used a space lens, which increased the amount of light being let in.”

This result suggests that supermassive black holes existed 470 million years after the Big Bang. This time is not enough for the black holes of first-generation stars, which are 10 to 100 solar masses, to grow to such sizes. Was there another possibility for an even larger black hole to form? In 2017, Dr. Natarajan suggested that the collapse of a primordial gas cloud could give rise to a black hole with a mass more than 10,000 times that of the Sun.

“We can imagine that one of them later grew into a young, very large black hole,” he said. Holtz. As a result, “at every subsequent moment in the history of the universe, there will always be some incredibly large black holes,” he said. Natarajan said, “The fact that they initially appear so large suggests that they are likely to eventually evolve into supermassive black holes.” But how does this happen? No one knows.