New research suggests that dark matter could be black holes formed in the first 1/1,000,000,000,000,000,000 seconds (one quintillionth of a second) after the Big Bang event.
For the past 50 years, there has been a puzzling issue within the scientific community that remains unresolved: the amount of visible matter in the universe is insufficient.
The term “visible matter” refers to stars, planets, cosmic dust, and all other celestial bodies, large and small. The interactions among these entities and their interactions with the environment are not enough to explain how the universe operates. According to NASA, the amount of matter must be about five times greater for observations to make sense.
The missing component is referred to by scientists as dark matter, as it is invisible and does not interact with light.
Illustration of dark matter connecting everything in the universe – (Image: NASA).
In the 1970s, American astronomers Vera Rubin and W. Kent Ford confirmed the existence of dark matter by observing the edges of a series of spiral galaxies. They found that the stars there were moving at such high speeds that they should have torn apart; the gravitational force and the matter present in the area could not keep these stars intact.
However, the stars continued to shine normally. This indicates that there exists an invisible form of matter in space that keeps this galaxy bound together.
“The observations of a spiral galaxy are not what we can deduce,” said astronomer Vera Rubin at that time. She built her research on a hypothesis proposed in the 1930s by Swiss astronomer Fritz Zwicky and initiated a search for this mysterious matter within the scientific community.
Since then, researchers have endeavored to find ways to observe dark matter, even designing massive machines to detect this elusive substance. Yet, they have still been ineffective.
In the early days of the search for dark matter, theoretical physicist Stephen Hawking suggested that dark matter might be hiding in black holes formed during the Big Bang. He dedicated his career to studying black holes and proposed many influential theories in physics, yet dark matter continued to evade Hawking’s sharp intellect.
Machine from the LZ Dark Matter detection project – (Image: The LZ Dark Matter).
However, in a new study conducted by the Massachusetts Institute of Technology (MIT), scientists analyzed the old theory from a modern perspective, revealing the composition of primitive black holes and suggesting the possibility of a completely new type of black hole.
“We leveraged Stephen Hawking’s renowned calculations about black holes, especially his results regarding the radiation emitted from them,” said David Kaiser, one of the study’s authors. “Black holes emerged when [we] attempted to solve the dark matter problem—they are byproducts of explaining the existence of dark matter.”
A trillionth of a second after the Big Bang
Since the concept of “dark matter” was formed, the scientific community has proposed various hypotheses about its nature, ranging from unknown particles to an alternate dimension. However, it wasn’t until recently that Hawking’s black hole theory has been brought into discussion.
“People didn’t really pay attention to it until about 10 years ago,” said co-author Elba Alonso-Monsalve. “That’s because black holes were very elusive—at the beginning of the 20th century, they were thought to be an interesting mathematical fact, rather than a physical entity.”
Now, we know that the centers of most galaxies contain a black hole, and advanced instruments have even detected gravitational waves generated by black hole collisions. This evidence indicates that black holes are real and numerous in the universe.
First image of a black hole – (Image: NASA).
“In fact, the universe is teeming with black holes,” Alonso-Monsalve stated. “But dark matter particles have yet to be found, even when searching in places where they should exist. I say this not to dismiss the possibility of dark matter being particles, nor to assert that dark matter exists in black holes. Both could be true. But now, the possibility of black holes being dark matter is being considered as feasible.”
In another recent study, results suggest that Hawking’s hypothesis seems plausible. However, the research conducted by Alonso-Monsalve and Professor David Kaiser takes a step further, exploring exactly what happens when primitive black holes form.
The study, published in early June in Physical Review Letters, reveals that primitive black holes likely formed at 1/1,000,000,000,000,000,000 seconds (one quintillionth of a second) after the Big Bang event. “They formed very, very early, even before protons and neutrons, the building blocks of everything, were created,” researcher Alonso-Monsalve said.
In the everyday world, we cannot observe protons and neutrons existing independently. Furthermore, they are composed of even smaller particles called quarks, which are held together by particles known as gluons.
