Black holes that originated instantly after the Big Bang may have played a role in the emergence of the initial stars in our universe.
In the early universe, a mysterious phenomenon known as primordial black holes (PBHs) may have played a significant role in the formation of the first stars. These ancient black holes, which are thought to have formed as a result of density fluctuations in matter, could have either accelerated or delayed the formation of Population III stars, depending on their mass and abundance.
Primordial black holes within a specific mass range, approximately asteroid-mass scales (10^17 to 10^22 grams), have been proposed as "cosmic seeds." These PBHs could have promoted matter clumping, thus speeding up star formation. However, if PBHs are too abundant or too massive, they can disrupt gas clouds through gravitational heating and delay star formation.
Simulations suggest that relatively low-mass PBHs, with abundances compatible with dark matter constraints, tend to speed up the formation of Population III stars by triggering earlier gas cloud collapse. Conversely, higher masses or higher abundances of PBHs can counterintuitively inhibit star formation by preventing gas clouds from cooling efficiently or by gravitationally disturbing proto-stellar environments.
The precise mass and abundance ranges of PBHs that would have the most significant impact on early star formation are still under active research. However, it is clear that PBHs could be critical for early structure formation and dark matter models, modulating the timing of the universe’s first stars.
Dark matter, which accounts for about 85% of the matter in the universe, remains effectively invisible. To boost early star formation, the black holes would need to be quite massive - about a thousand to ten thousand times the mass of our sun. Interestingly, PBHs with masses smaller than around 100 times that of the sun wouldn't increase density fluctuations.
Some primordial black holes could have acted like "cosmic seeds," helping matter clump together earlier than expected. However, if there are too many or if primordial black holes are too massive, they would cause the first stars to form much too early - before we see any signs of them.
The effects of PBHs on the formation of the first stars would show up during the cosmic dawn, roughly 100 to 200 million years after the Big Bang. The team's research into this fascinating topic is available as a preprint on the paper repository arXiv. This nuanced understanding of PBHs highlights their potential role in shaping the early universe and the formation of the first stars.
- "Research in the field of science and astronomy suggests that an excess of massive primordial black holes could disrupt gas clouds and delay the emergence of medical-conditions related to the universe's first stars."
- "Advancements in technology have enabled scientists to simulate various scenarios involving different mass ranges of primordial black holes, thus shedding light on their role in the news of early structure formation and star birth."
