A hypothesis suggesting that black holes could be behind the accelerated expansion of our universe has sparked controversy among astronomers.
Artistic representation of a black hole PHOTO: Shutterstock
Astronomers would have found tantalizing evidence that “dark energy, the mysterious energy driving the accelerated expansion of our universe, may be related to black holes“, writes Live Science.
Dark energy makes up about 70% of our universe and is thought to have arisen in the wake of the Big Bang 13.8 billion years ago to fuel the growth of the cosmos.
But it is not known exactly where this mysterious force comes from. In recent years, some astronomers have proposed a radical theory that, instead of being spread diffusely throughout space, dark energy may arise from the heart of giant black holes. Others, however, have categorized this proposal as aberrant.
Now, a new study claims to have found the first hints of a link between the two seemingly unrelated phenomena: “a match between the increasing density of dark energy and the increasing mass of black holes as the universe ages.”
The researchers published their findings on October 28 in the Journal of Cosmology and Astroparticle Physics.
“If you ask the question: Where do we see gravity as strong as it was at the beginning of the universe? The answer is at the center of black holes”study co-author Gregory Tarlé, a professor of physics at the University of Michigan, said in a statement.
To look for clues that dark energy might be linked to black holes, the researchers used the Dark Energy Spectroscopic Instrument (DESI) on the Nicholas U. Mayall 4-meter Telescope in Arizona, which pinpoints the positions of millions of galaxies every month to study how the universe has expanded to the present.
This allows astronomers to infer the density of dark energy over the lifetime of the universe from the rate at which the cosmos is expanding.
By comparing this data for dark energy with the growth of black holes at different stages of the universe’s life, the researchers made an intriguing observation.
“The two phenomena were consistent with each other – as new black holes were made in the death of massive stars, the amount of dark energy in the universe increased in the right way. This makes it more plausible that black holes are the source of dark energy.”co-author Duncan Farrah, a professor of physics at the University of Hawaii, said in the statement.
If the hypothesis is confirmed, it could help solve a growing puzzle in cosmology.
For years, astronomers have found that the universe appears to be expanding at different rates depending on where they look—a problem they call the “Hubble tension.”
Some of the measurements confirm the best current understanding of the universe, while others threaten to destroy it.
However, despite the intriguing connection, astronomers say much more observations and further experiments are needed before any firm conclusions can be reached.
