A new theory suggests that the expansion of the universe could cause all matter objects, including black holes, to grow in mass.
According to Space.com, the new hypothesis argues that, as the universe expanded outwards after the Big Bang, all objects with mass evolved with it. Black holes – the most massive objects that exist in the universe – grow the most.
This hypothesis stems from gravitational ripples in space-time – what happens when two massive black holes are locked in orbit, spiraling inward and colliding. Since 2015, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo interferometer have observed many of these black hole mergers.
But the waves hide a mystery. Based on the estimated size distribution of stars in the universe, black holes must be about 40 times less massive than the Sun. But data taken from these gravitational waves show that many black holes are more than 50 times the mass of the Sun, and some are close to 100 times the mass of the Sun.
A common explanation for this is that black holes evolve over time by sucking up gas, dust, stars, and even other black holes.But because black holes often form after massive stellar explosions known as supernovas, many black holes appear in regions of space without any of the matter above.
Astronomers have proposed alternative explanations, but all have suggested unprecedented changes to scientists’ current understanding of the life cycles of stars. And no one has been able to account for the amazing size diversity of merging black holes that gravitational wave observatories have detected.
A new paper published November 3 in The Astrophysical Journal Letters explains that the growth in mass of black holes is not the result of matter attraction, but rather expansion. of the universe.
This means that all black holes – including the merging black holes discovered in gravitational wave experiments, the black holes that roam the outskirts of our galaxy, and even the supermassive black holes. giant at the center of most galaxies – growing over time.To prove their hypothesis, the researchers chose to model two black holes merging in an evolving universe, rather than static universes that other research groups have built to simplify complex equations. complex.
By simulating millions of star pairs – from birth to death, the team was able to study dead stars to form pairs of black holes and link how much they grow to expansion. of the universe. After comparing the predictions made using the cosmological model with data from LIGO and Virgo, they were surprised to find that they matched very well.
If this hypothesis is correct, then everything with mass will get larger and larger – the Sun, neutron stars, planets, and even humans. Of course, this association is much weaker for us than for a black hole.
The team hopes that, as gravitational wave detectors become more advanced, they will have more data to further test the hypothesis’s accuracy.