Observations of ancient dormant galaxies with black holes at their centers suggest that giant black holes may be a source of dark energy and the accelerating expansion of the universe.
The laws of physics suggest that gravity should cause the universe to contract, but a mysterious force that physicists call dark energy seems to counteract this, causing the universe to expand at an accelerated rate.
One possible explanation is that the source of this dark energy is black holes, but experimental evidence to conclusively support this idea is still lacking.
Chris Pearson At the Rutherford Appleton Laboratory in Harwell, England, his colleagues compared groups of galaxies with black holes at their centers. They calculated that the black hole’s mass increased by a factor of 7 to 20, which he cannot fully explain by absorbing stellar matter or merging with other galaxies.
Instead, Pearson and his team attempted to explain growth by proposing that it is related to the accelerating expansion of the universe. ,” Pearson says. “Adding to these astrophysical processes of black hole growth, and the fact that black holes may contain dark energy, coupled with the expansion of the universe, we can conclude that this It turns out that we can explain the discrepancy.”
The model they used included an interpretation of Albert Einstein’s general theory of relativity that black holes contain vacuum energy. This energy is a kind of energy that exists in all space due to the existence and disappearance of quantum particles. “When we calculated the totals, we found that these black holes could actually explain all that is needed to balance the universe and this dark energy,” says Pearson.
If black holes are indeed the source of the universe’s dark energy and its expansion, it would also solve another prominent cosmic conundrum. That’s what happens at the center of a black hole, the so-called singularity, where the laws of physics break down.
A black hole with a core of dark energy bypasses the need for a singularity, but there has been no easy way to test this. “These are just theories so far. Now we have observational evidence for black holes with dark energy cores,” says Pearson.
The researchers used the estimated rate of star formation, extrapolated from a sample of observed galaxy growth, to calculate how much dark energy would be produced on a cosmic scale. They found that it could explain the accelerating expansion of the universe.
However, this may not be true if the star formation rate estimate is wrong. In addition, the researchers compared young galaxies that are very far away with older galaxies that are nearby, and hypothesized that this is how galaxies evolve, estimating the growth rate of black holes, but in this way It may not grow.
This explanation could be strengthened by more galaxy observations, or by looking at signatures in the cosmic microwave background (CMB), a cloud of radiation produced shortly after the universe first formed. says Pearson. If their ideas are correct, black holes can influence the expansion of the universe and the CMB in distinct ways and can be detected. More evidence could be obtained by measuring the speed at which black holes merge. This is also affected by the nature of dark energy.
It’s a solid, rational explanation for the observation, he says. Andy Taylor However, the interpretation of Einstein’s theory of relativity, which he uses to explain the growth of black holes, has not been extensively studied. “There are some good arguments out there, but it should be noted that they are not built on established theoretical principles, but on more speculative models. ”
He says more observational data needs to be collected before black holes are the source of dark energy.
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Corrected article on February 17, 2023
We have corrected the details of the black hole growth observed in this study.